Tesi sul tema "Physiological aspects"

The purpose of this study was to assess the energy demands of a 2,000 meter race simulation (RS) for national level oarswomen; as evaluated on a rowing ergometer (RE). A Progressive Intensity Test (P.I.T.) was also performed on the RE to further evaluate the RS. Six national level oarswomen (X values: age= 24.5 yrs., ht= 179 cm, wt= 75 kg), all current national team candidates (1988), participated in this investigation. A 6 1/2 minute tape recorded water race was used to execute a 2,000 meter RS on a Dr. Gjessing Ergorow ergometer. The tape recording was an actual race tape that was respliced to last exactly 6 1/2 minutes. Metabolic and respiratory exchange variables were continuously monitored by an open circuit method, utilizing a Beckman Metabolic Measurement Cart interfaced on-line with a Hewlitt Packard 3052A data acquisition system. The energy demands were calculated from metabolic variables, total oxygen cost and the analysis of excess post-exercise oxygen consumption (recovery V0₂).Results indicated a mean V0₂max. of 3.85 1.min⁻¹ , mean net V0₂ of 24.48 1 and a mean recovery V0₂ of 4.92 1. This represented the aerobic cost of the event at approximately 80% or 4/5ths of the total energy cost while the anaerobic contribution was approximately 20% of l/5th of the total energy cost. During the RS, V0₂ values rapidly increased to 90% of mean V0₂max. (3.85 l.min⁻¹) in the first two minutes. Mean max. VE (BTPS) RS value was 122.4 1.min⁻¹. VE plateaued after two minutes and remained around 90% of P.I.T. mean max. VE for the final 4 1/2 minutes. Mean max. excess C0₂ for RS was 19.81 ml.kg⁻¹.min⁻¹. The average maximal heart rate, as recorded in the RS was 192.8 bpm. The results of this study indicate the high aerobic demands and tremendous exercise intensity involved in the 2,000 meter RS.
Education, Faculty of
Curriculum and Pedagogy (EDCP), Department of
Graduate

Sprint cross-country skiing is a physiologically and technically complex discipline, performed as a time-trial qualification race and three subsequent knock-out heats. The racing time in a single heat is 2-4 min and is comparable to other middle-distance sports. However, sprint skiing is performed in varied terrain at constantly changing intensities using multiple techniques involving the arms and the legs to various degrees. The overall objectives of the current thesis were to examine physiological and biomechanical aspects associated with sprint skiing performance in the skating technique in elite skiers: 1) while treadmill roller skiing in the laboratory (studies I-IV), 2) during sprint competitions on snow (studies IV-V) and 3) for relationships between laboratory characteristics and performance on snow (studies IV-V). Studies I-III are comparative studies in which physiological characteristics, mechanical efficiency and gross kinematics during treadmill roller skiing were compared between male world-class and national level sprint skiers (studies I-II), and between men and women matched for performance level (study III). Study I showed that maximal aerobic capacity, gross efficiency and high speed capacity differentiated world-class from national level sprint skiers. The study also indicated that low and moderate intensity endurance training and maximal speed training is important in attaining an international level in sprint skiing. Study II demonstrated that world-class sprint skiers had a higher gross efficiency than national level skiers. A general linear relationship between work rate and metabolic rate existed, indicating that gross efficiency at moderate and high work rates provides useful information about crosscountry skiers in standardized conditions during treadmill roller skiing. Furthermore, worldclass skiers used longer cycle lengths and lower cycle rates at a given speed and generated higher maximal speeds. In study III, men showed a 17% higher peak treadmill speed at a short and long incremental test compared to women. These gender differences were slightly greater than findings in comparable endurance sports. The majority of gender differences in performance could be explained by higher maximal oxygen uptakes and lower fat percentages in men. Men and women showed similar gross efficiency. However, women showed higher fractional utilization of maximal oxygen uptake at the anaerobic threshold. In studies IV-V, elite male skiers were analyzed for speeds, work rates, technique choices and gross kinematics during two sprint time-trial competitions on snow. Furthermore, the skiers were tested for physiological and kinematical characteristics in the laboratory. Study IV analyzed the time-trial of an international sprint competition. The results showed that performance on uphill and flat terrain strongly determined sprint time-trial performance, and that performance in the last half of the race differentiated most between skiers. Estimated work rates on an uphill section of the race were approximately 60% higher than the capacities which the skiers are able to cover aerobically. Peak oxygen uptake, gross efficiency, peak treadmill speed and peak cycle length were strongly related to sprint time-trial performance, particularly to the uphill and flat sections during the last part of the race. Study V analyzed a simulated sprint race by using a high end differential global navigation satellite system with simultaneous tracking of both GPS and GLONASS satellites. This provided an opportunity for more detailed analysis of cross-country skiing. Skiers encompassed a large speed range (2.9–12.9 m·s-1) and multiple transitions between skiing techniques (range: 21–34 transitions). The results demonstrated that performance in the uphill sections had the strongest correlation to sprint performance, and that the faster skiers used the G3 technique to a greater extent than the slower skiers. Thus, this provides new knowledge on physiological and biomechanical aspects of sprint skating performance, particularly that both the maximal aerobic and peak speed capacities differed between world-class and national level sprint skiers. Furthermore, gross efficiency, while treadmill roller skiing provides relevant information strongly related to sprint performance level. Better skiers also employ longer cycle lengths at the same absolute speeds and at individual peak speeds. The gender differences in performance were slightly larger than expected; however, most of these differences could be explained by a higher maximal oxygen uptake and a lower fat percentage in men. Furthermore, the variations in speeds, work rates and techniques and, especially, speed in uphill and flat terrain are important to the skiers’ total time-trial performance. Better sprint performance is related to more application of the G3 technique and to longer cycle lengths within this technique. Faster skiers showed higher peak oxygen uptake, gross efficiency and high speed capacity. These capacities were specifically correlated to the ability to maintain high speed on uphill and flat terrain throughout a sprint race.
Sprintlangrenn er ein fysiologisk og biomekanisk kompleks disiplin som blir utført som ein prolog og tre etterfølgjande utslagsløp. Konkurransetidene i kvart enkelt heat er 2-4 min og kan samanliknast med andre mellomdistanseidrettar. Sprintlangrenn blir imidlertid gjennomført i kupert terreng og med varierande arbeidsintensitet og innslag av ulike teknikkar som involverer underkropp og overkropp i ulik grad. Den overordna målsetjinga med denne avhandlinga var å undersøke fysiologiske og biomekaniske aspekt som er assosiert med prestasjonen i sprint skøyting hos elite langrennsløparar: 1) på rulleskitredemølle i laboratoriet (studia I-IV), 2) i sprintkonkurransar på snø (studia IV-V), og 3) for samanhengar mellom laboratorium-karakteristikkar og sprintprestasjonen på snø (studia IV-V). Studia I-III undersøker forskjellar i fysiologiske karakteristikkar, mekanisk effektivitet og kinematikk mellom mannlege verdsklasse og nasjonal klasse sprintlangrennsløparar (studia III) og mellom mannlege og kvinnelege sprintlangrennsløparar på tilsvarande prestasjonsnivå (studie III). Studie I viser at maksimal aerob kapasitet, mekanisk effektivitet og hurtigheit skil verdsklasse frå nasjonal klasse sprintlangrennsløparar. Studiet indikerer også at låg- og moderat-intensiv uthaldstrening og maksimal hurtigheitstrening er viktig for å nå internasjonalt nivå i sprintlangrenn. Studie II viser at verdsklasse sprintlangrennsløparar har betre mekanisk effektivitet enn løparar på nasjonalt nivå. Studiet viser ein generell lineær samanheng mellom arbeidsratar og energiforbruk og indikerer at målingar av mekanisk effektivitet gir nyttig og valid informasjon om langrennsløparar som blir samanlikna under standardiserte vilkår på rulleskitredemøller. Studiet demonstrerer også at verdsklasse løparane har lengre sykluslengder og lågare syklusfrekvens på ei gitt fart. Studie III viser at menn oppnår 17 % høgre fart enn kvinner både på ein kort og ein lang prestasjonstest med trinnvis aukande fart på rulleskitredemølla. Resultata indikerer at prestasjonsforskjellane mellom kjønna hovudsakleg kan forklarast av høgare maksimalt oksygenopptak og lågare feittprosent hos menn, og at forskjellane er noko større enn det litteraturen viser i andre tilsvarande uthaldsidrettar. Kvinner og menn har lik effektivitet, mens kvinner har høgare prosentvis utnytting av maksimalt oksygenopptak ved anaerob terskel. I studia IV-V vart fart, arbeidsratar, teknikkval og kinematikk undervegs i sprintkonkurransar undersøkt. Vidare blei samanhengar mellom fysiologiske og kinematiske karakteristikkar i laboratoriet og sprintprestasjonen på snø undersøkt. I studie IV vart prologen i ein internasjonal sprintkonkurranse analysert. Resultata viser at prestasjonen i motbakke og i flatt terreng er sterke forklaringsvariablar for den totale prologprestasjonen. Studiet indikerer også at prestasjonen i siste halvdelen av løypa skil løparane mest. Estimerte arbeidsratar i motbakke indikerer eit totalt arbeid omlag 60% høgare enn det løparane klarer å dekke med aerob energi. Maksimalt oksygenopptak, mekaniske effektivitet, fartskapasitet og sykluslengde var sterkt relatert til sprintprestasjonen, og spesielt til farta i flatt terreng og motbakkar i siste halvdelen av løpet. I studie V vart ein simulert sprintprolog analysert ved bruk av ein høgteknologisk differensial GPS, med svært høg samplingsfrekvens og nøyaktigheit, som hadde samtidig mottak av GPS- og GLONASS-satellittar. Løparane gjennomførte sprintkonkurransen i variert terreng, noko som førte til eit spenn i hastigheiter frå 2.9 til 12.9 m·s-1 og som inkluderte 21–34 teknikkendringar. Motbakkeprestasjonen var høgast korrelert til total prestasjon, og betre skiløparar brukte dobbeldansteknikken i større grad, samanlikna med mindre gode løparar. Samanfatta så bidreg denne avhandlinga med ny kunnskap om fysiologiske og biomekaniske aspekt av sprintlangrenn i skøyting. Det viser at både maksimal aerob kapasitet og fartskapasitet skil verdsklasse frå nasjonal klasse sprintlangrennsløparar. Det er også vist at målingar av mekanisk effektivitet på rulleskitredemølle gir valid informasjon og er sterkt relatert til prestasjonsnivået til løparane. Dei beste løparane bruker lengre sykluslengder både på same submaksimale fart og på si høgste individuelle fart. Forskjellane mellom mannlege og kvinnelege sprintløparar i prestasjon er noko større enn forventa. Det meste av desse kjønnsforskjellane kan forklarast av at menn har høgare maksimalt oksygenopptak og lågare feittprosent. Undervegs i sprintprologar viser løparane store variasjonar i fart, arbeidsratar og vekslar stadig mellom ulike teknikkar. Spesielt er farta i motbakkar og flatt terreng mot slutten av løpa betydningsfull for prologprestasjonen. Betre prologprestasjon er linka til meir bruk av dobbeldansteknikken og lengre sykluslengder innan denne teknikken. Betre utøvarar har også høgare maksimalt oksygenopptak, effektivitet og fartskapasiet, noko som vart relatert til evna til å oppretthalde høg fart i motbakkar og flatt terreng gjennom eit sprintløp.

The effect of the key physiological parameters on the production of solvents in the acetone-butanol fermentation using the anaerobic bacterium Clostridium acetobutylicum was examined in this work.
The theoretical solvent yield was calculated based on expressing stoichiometric relationships between the substrate and the products of the process. The maximum theoretical yield under the acceptable process conditions was established ranging from 38.6% to 39.9%.
A linear correlation was established between the production of solvents and gases which varied with the mixing rate of the fermentation system.
Elevated hydrogen partial pressure affected the metabolism of C. acetobutylicum resulting in increased butanol and ethanol yields (based on glucose) by an average of 18% and 13%, respectively.
A mathematical model for the batch acetone-butanol fermentation was formulated using original experimental data for the microbial growth, sugar consumption and metabolite biosynthesis. This model was used for computer process simulations. Parametric sensitivity analysis indicated the importance of the key process parameters.
A method of systems analysis was applied in analysing pronounced physiological differences in the performance of one of the C. acetobutylicum culture strains. The cellular transport mechanism for substrate (glucose), solvents and acids through the cell membrane was established to depend on its permeability and the number of sugar transport "sites". Experimental results obtained from the study of the uptake of 3-0-methyl glucose (0.7mM) by the "normal culture" and the "retarded culture" confirmed the theoretical predictions of a slower transpost in the "retarded culture". The theoretical predictions were further confirmed by additional experimental results.
A mathematical "Physiological State Model" was developed which includes the culture physiological parameters as well as the internal and the external culture conditions. Using this mathematical model the standard and the substandard acetone-butanol fermentations could be simulated.
These results demonstrate the application of the method of systems analysis in elucidation of the role played by the key culture physiological parameters in the fermentation process.

Obesity continues to be a major cause of morbidity and mortality and worldwide prevalence rates continue to rise. The cornerstone for treating obesity remains diet and lifestyle, with the ultimate goal being normalising those parameters that are associated with ill health, for example hyperinsulinaemia and insulin resistance. Because obesity predominantly develops due to a mismatch between energy intake and utilisation, this thesis looked at the effects of dietary interventions upon Resting Energy Expenditure (REE) and substrate oxidation. In addition, the impact of popular dietary interventions upon body composition and insulin resistance was examined. When phenotypic characteristics were investigated before and after weight loss by using hypocaloric diets, which differed in fat and carbohydrate content, Fat-Free Mass (FFM) and Fat Mass (FM), were strong predictors of REE before and after the intervention and weight loss rather than the specific dietary intervention, significantly predicted post intervention REE. Fasting fat oxidation was found to be lower in obese subjects and they had a lower postprandial response to a high fat challenge. This implied that a diet high in fat is more likely to promote a positive energy balance an ultimate weight gain. The final study compared 4 popular dietary interventions. Each was equally effective at achieving clinically significant weight loss and improvements in insulin sensitivity. Although none was significantly more superior, there was a trend supporting three of the diets (Atkins’, Weight Watchers and Rosemary Conley) above the other (Slim-Fast) and it was the pattern of weight loss, i.e. mainly loss of FM, which proved beneficial with regards to improving insulin sensitivity. In summary, this thesis confirms that REE is mainly predicted by FFM and FM and that there is diminished fat oxidation on obese subjects. What this thesis also adds to previous research that it if a specific diet can improve the pattern of weight loss, this can be clinically beneficial.

The intake of water and electrolytes is inseparable from feeding by natural or artificial means and careful attention to salt and water balance is a vital component of perioperative care and of nutritional support. Nutritional support with water and sodium restriction in post-intensive care patients with oedema, dilutional hypoalbuminaemia and fluid excess of 10 L, cleared oedema over 7-10 days, with a 1 g/L rise in serum albumin for every kg loss in weight. Return of gastrointestinal function was also observed. Accordingly, 20 patients, undergoing colonic surgery, were randomised to receive standard (>3 L water and 154 mmol sodium/day) or restricted postoperative fluids (<2 L water and 77 mmol sodium/day). Solid (72.5 vs 175 min) and liquid phase (73.5 vs 110 min) gastric emptying times were significantly longer in the standard group on the 4th postoperative day and associated with a three day longer hospital stay. In volunteers receiving 2 L of 0.9% saline and 5% dextrose infusions, on separate occasions over one hour, haematocrit and serum albumin concentration fell, mainly due to dilution. While dextrose was rapidly excreted, two-thirds of the saline was retained after 6 h. Following 1 L infusions, plasma renin and angiotensin concentrations decreased more after saline than dextrose (P<0.04). Responses of aldosterone, atrial natriuretic peptide and vasopressin were not significantly different. Comparing 2 L infusions of saline and Hartmann's solution, volunteers excreted more water (median 1000 vs 450 mL) and sodium (122 vs 73 mmol) after Hartmann's. Hyperchloraemia and reduced bicarbonate were noted after saline alone. Whereas fluctuations in water balance are dealt with efficiently through osmoreceptors and vasopressin, and sodium deficiency by volume receptors and the renin angiotensin aldosterone system, the mechanism for dealing with sodium and chloride excess appears relatively inefficient. Natriuretic peptide responds to volume expansion rather than sodium gain.

1. The septal structure of C. cinereus and N. crassa was examined via fluorescence microscopy and transmission electron microscopy. The septa of these organisms were shown to contain two plates of chitin, not one, as had been previously believed.2. The effect of the fluorochrome Calcofluor White on chitin synthesis in vivo and in vitro was investigated. Growth of C. cinereus in media seeded with the dye caused abnormal deposition of chitin at points of growth i.e. tips, septa, hook cells and clamps. However, high concentrations of the dye were required to have an effect on the chitin content and growth rate of the mycelium. X-ray crystallography showed that chitin synthesized in the presence of the fluorochrome was less crystalline than chitin synthesized when the dye was absent. It would appear, therefore, that Calcofluor binds to nascent chitin inhibiting its crystallization into microfibrils. It was concluded that chitin synthesis is a two-step process involving polymerization and subsequent crystallization.3. A range of fungi and growth forms were probed for the presence of actin using the actin-specific fluorochrome rhodamine phalloidin. Only U. phaseoli germlings and C. albicans yeast cells appeared to contain the protein. It is suggested that the failure to visualize actin in the other organisms examined is linked to their cell wall structure which prevented penetration of the rhodamine phalloidin to sites of actin localization.4. In the light of these results, mechanisms of hyphal growth are discussed and a model for the polarity of apical extension is presented.

The aim of these experiments was to investigate learning and memory extensively in two nonverbal domains (olfactory and visual), and to determine similarities and differences in the function of the neural substrates that subserve these modalities. Two complementary methodological approaches were taken: (1) examination of learning and retention in patients with resection from left (LR) or right (RR) temporal lobe, and (2) study of brain function via Positron Emission Tomography (PET) of healthy subjects during memory processing.
Two parallel recognition tests were developed (one olfactory, one visual) that examined memory at three stages: following a single exposure to test stimuli, after four exposures, and following a 24hr delay interval. In the olfactory patient study, LR and RR groups performed significantly worse than the healthy control subjects, with no difference between the patient groups; thus suggesting a lack of hemispheric superiority for this task. The PET study of healthy individuals supported the bilateral participation of piriform cortex during olfactory recognition. The results from these two studies, along with findings from animal work, suggest that the piriform cortices may play a role in odor memory processing, not simply in perception.
On the face memory task, LR and RR patients showed different results. Only RR patients were impaired, while LR patients did not perform differently from controls. This unique face learning paradigm was sensitive to right temporal lobe damage, and correctly classified patients by side of resection with a sensitivity rate of 82% and specificity rate of 79%, suggesting its possible utility as a clinical tool. PET face memory findings indicated greater participation of fusiform regions during long-term recognition, and greater right prefrontal activity during short-term recognition, when these conditions are directly compared to each other.
Finally, PET was used to study the same healthy subjects performing parallel odor and face working-memory tasks, focusing on regions previously shown to be important for working memory. Results revealed similar regions of activation in dorsolateral prefrontal cortex in the two modalities. This indicates an overlap in the brain regions that process olfactory and visual information when the same cognitive manipulations are being carried out online.

The purpose of this research was to examine the effects of a premovement silent period (PSP), and an involuntary small amplitude countermovement (CM) on the maximal height of the squat jump (SJ). Fifteen elite male volleyball players (20.6 ± 1.6 yrs) and thirteen untrained males (20.2 ± 1.7 yrs) performed ten maximal effort SJs from identical starting positions. The electromyographic activity of the vastus lateralis and biceps femoris was measured in conjunction with the vertical ground reaction force, and the vertical displacement measured by a cable-extension transducer. The presence of a PSP or small amplitude CM did not increase maximal SJ height significantly (p > 0.05). These findings indicate that in the SJ, facilitation effects of the PSP and small amplitude CM are minimal. This is important to past and future studies utilizing the SJ, as it is often difficult for individuals to perform SJs with no detectable CM.
School of Physical Education

Plasma choline levels have been reported to be significantly reduced in athletes at the endof prolonged, exhaustive exercise (marathon running), and this may affect the release of acetylcholine at the neuromuscular junction (16). The purpose of the present investigation was to examine the influence of two levels of choline (from soy lecithin) ingestion on plasma choline levels and exercise performance. Ten endurance-trained male cyclists exercised on an electrically resisted ergometer for 105 minutes at a load equal to 70% V02 max, followed by an all-out, self-paced 15 minute performance ride on an isokinetic cycle. Three randomly ordered trials were performed four hours after the feedings of (A) 0.0 g, (B) 1.1 g, or (C) 1.8 g choline. Dietary intake of choline was controlled. Before and after the trials, blood samples were drawn and analyzed for serum choline (umol/liter) using an HPLC method. Feedings of 1.1 g and 1.8 g of choline significantly (p < 0.05) elevated serum choline values compared to control (A = 34.16 [± 0.63], B 38.17 [+ 0.96], and C = 42.32 [+ 0.59]).Post-exercise serum choline values, however, were not significantly different (p > 0.05) from pre-exercise levels. In addition, there were no significant differences (p > 0.05) in performance between placebo, 1.1 g, and 1.8 choline trials (2.11 x 105, 2.07 x 105, 2.07 x 105 Newton-meters, respectively). This study indicates a dose response to choline ingestion, with no effect on performance.
School of Physical Education

This study investigated the influence of human morphology upon selected physiological, biomechanical and psychological responses to horizontal locomotion. In so doing, it was possible to evaluate the effectiveness with which morphology-normalised speeds of walking and running reduced the between-subject variability that is inherent in human locomotor responses. Twenty caucasian males were divided into two groups on the basis of stature - ten subjects in each of a "short" category (<170cm) and a "tall" category (>185cm). All subjects were habituated to treadmill locomotion prior to exposure to three walking treatments (0.83, 1.39 and 1.94m.s⁻¹) and three running treatments (2.50, 3.06 and 3.61m.s⁻¹). During each of these five-minute locomotor conditions, energetic (V02), kinematic (cadence and stride length) and psychophysical (central and local RPE) data were captured. From these data, lines of best fit were calculated for each subject, allowing for a prediction of the abovementioned locomotor variables from known absolute rates of progression. Using suitable regression equations, subject responses to morphology-normalised speeds of walking and running were effectively extrapolated. When the rate of progression was expressed in absolute terms (m.s⁻¹), significant differences (P <0.05) were found between the stature-related groups with respect to both energetic and kinematic locomotor responses. Such differences were successfully eliminated when use was made of locomotor speeds relativised on the basis of morphology. This study concludes that the use of appropriately prescribed morphology-normalised rates of progression are effective in reducing the variability in locomotor responses between subjects differing significantly in stature.

[Conclusions] l) The two forms of human locomotion, walking and running, are distinctly different and in evaluating these gait patterns consideration must be given to this fact. 2) The impression created by the energy cost curves, that there is a single locomotor interface for both walking and running is a false one . There are two distinctly different locomotor interfaces, the walk-to-run interface and the run-to-walk interface. The former appears to correspond with the "metabolic intersection point" and therefore has some metabolic significance. The latter appears to be merely an "overshoot" of the walk-to-run interface and presently has no apparent metabolic significance. 3) Because the walk-to-run interface speed corresponds with the intersection point of the energy cost curves, physiological responses to walking and running at this speed do not differ significantly. However, cadence and stride length patterns for these two locomotor patterns are distinctly different at this point. 4) The identification of single physiological or kinematic factors during perceptions of exertion in any given situation is an extremely difficult if not impossible task. Perceived exertion should therefore be considered a multi-factorial concept and should be evaluated as such. 5) The use of relative speed as a technique for reducing inter-subject variability in physiological and kinematic factors is worthless unless diverse ranges in morphological linearity are a characteristic of one's subject pool

The objective of the present study was to establish effective combinations of marching speed and backpack load in order to meet specific military requirements. Thirty infantrymen from the South African National Defence Force (SANDF) comprised the sample and experimental procedures were conducted in a laboratory setting using a Cybex Trotter treadmill. Sixteen conditions were set up which included combinations of four speeds (3.5, 4.5, 5.5, and 6.5 km.h⁻¹) and four backpack loads (20, 35, 50, and 65kg). Each subject was required to complete 8 of the sixteen conditions, each consisting of a six-minute treadmill march. Physiological data (heart rate, ventilation and metabolic responses), kinematic gait responses (step-rate and stride length) and perceptions of exertion (“Central” and “Local” RPE) were collected during the third and sixth minutes of the treadmill march and areas of body discomfort were identified post-march. Responses revealed five distinct categories of exertional strain. Three marches constituted “nominal” (below 40% VO₂max) and three “excessive” strain (above 75% VO₂ max). These represent combinations of extreme military demands and are highly unlikely to be utilised by the military. Three “tolerable” levels of required effort were recommended and these 10 combinations were further divided into three sub-categories. The “moderate” stress marches were identified as “ideal” for prolonged marches and had statistically similar responses of working heart rates (range of 118 bt.min⁻¹ to 127 bt.min⁻¹), energy expenditure (26 kJ.min⁻¹ and 27 kJ.min⁻¹) and ratings of perceived exertion (“Central” ratings of 10 and 11). Thus, marching at 5.5 km.h⁻¹with 20kg, 4.5 km.h⁻¹ with 35kg or 3.5 km.h⁻¹ with 50kg all require a similar energy cost. Four “heavy” category marches were identified for possible use when the duration of the march is reduced. During these marches responses were statistically similar with heart rates ranging from 127 bt.min⁻¹ to 137 bt.min⁻¹, energy expenditure from 32 kJ.min⁻¹ to 37 kJ.min⁻¹ and “Central” ratings of perceived exertion were 12 and 13. When short, high intensity marches are necessary, then combinations from the “very heavy” category may be utilised but with caution. During these marches, soldiers were taxed between 65% and 75% of VO2 max. The results of this study clearly demonstrate that the interplay between speed and load needs to be adjusted when determining “ideal” combinations for specific military demands. Essentially, if speed is of the essence then load must be reduced, and if heavy loads need to be transported then speed must be reduced.

Thirty outpatients being treated at Wilford Hall USAF Medical Center Department of Behavioral Health Psychology were randomly assigned to either a relaxation/imagery training class (R/I), a short-term psychotherapy group (P/G) or a no treatment control group. Subjects had psychological, physiological and immunological data taken before and after treatment. Results indicated that support for the hypothesis that relaxation/imagery training improves the psychological, physiological, and immunological functioning of participants was found.

Relationships of negative psychological conditions with general status of cell-mediated and humoral immune systems were investigated. A unique approach was utilized in that indexes representing multiple aspects of each branch of the immune system were employed to better indicate general immunological status. Differences in emotion-immune interactions between males and females were demonstrated. Results indicated a positive relationship between Trait Anger and Cell-Mediated Immunological Index. Particular criticisms of previous psychoneuroimmunological research were met by addressing sex differences and differences in various conditions of anger and depression, as well as through assessment of cumulative effects of negative emotions on immune system status. Directions for future research in eddressing similar issues are suggested. In general, results provide support for validity of mindbody interactionism and imply the need for revision of standard medical and psychological treatment.

The purpose of this study was to determine if mild heat stress induced by wearing a wet suit while swimming in relatively warm water (25.4 ± 0.1°C) increases the risk of heat injury during the subsequent cycling and running stages. Specificlly, during an Olympic distance triathlon in a hot and humid environment (32°C & 65% RH). Five male triathletes randomly completed two simulated triathlons (Swim=30 min; Bike=40 km; Run=10 km) in the laboratory using a swimming flume, cycle ergometer, and running treadmill. In both trials, all conditions were identical, except for the swimming portion in which a full length, sleeveless neoprene wet suit was worn during one trial (WS) and a competitive brief swimming suit during the other (SS). The swim portion consisted of a 30 min standardized swim in which oxygen consumption (V02) was replicated, regardless of WS or SS. During the cycling and running stages, however, the subjects were asked to complete the distances as fast as possible. Core Temperature (T) was not significantly different between the SS and WS trials at any time point during the triathlon. However, mean skin temperature (TSk) and mean body temperature (Tb) were higher (p<0.05) in the WS at 15 (TSk=+4.1°C, Tb=+1.5°C) and 30 min (TSk=+4°C, Tb=+1.6°C) of the swim. These TSk and Tb differences were eliminated by 15 min of the cycling stage and remained similar (p>0.05) through the end of the triathlon. Moreover, there were no differences (p>0.05) in V02, heart rate (HR), rating of perceived exertion (RPE), or thermal sensation (TS) between the WS and SS. Additionally, no significant differences were found in cycling (SS=1:14:46 ± 2:48 vs. WS=1:14:37 ± 2:54 min), running (SS=55:40 ± 1:49 vs. WS=57:20 ± 4:00 min) or total triathlon times (SS=2:40:26 ± 1:58 vs. WS=2:41:57 ± 1:37 min). Therefore, the primary finding was that wearing a wet suit during the swimming stage of an Olympic distance triathlon in 25.4°C water does not adversely affect the thermal responses or the triathlete's ability to perform on the subsequent cycling and running stages.
School of Physical Education

This thesis investigates the hypothesis that emotions play an influential role in cognition. Interference between facial emotional expression processing and selected tasks is measured using a variety of experimental methods. Prior to the main experimental chapters, the collection and assessment (Chapter 2, Exp. 1) of stimulus materials is described. Experiments 2-11 then concentrate on the likelihood of interference with other types of information from the face. Findings using a Garner design suggest that, although identity processing may be independent of expression variation, expression processing may be influenced by variation in identity (Exps. 2-4). Continued use of this design with sex (Exps. 6-7) and gaze direction (Exps. 9-10) information appears to support the (mutual) independence of these facial dimensions from expression. This is, however, in contrast to studies that indicate the modification of masculinity judgements by expression (Exp. 5), and the interaction of gaze direction and expression when participants rate how interesting they find a face (Exp. 8). Further to this, a search task (Exp. 11) shows that slower responses to an angry (cf. happy) face looking at us, may be due to the presence of an aversive mouth. Experiments 12-15 test for interference in the field of time perception: complex interactions between expression and encoder and decoder sex are indicated. Finally, Experiments 16-17 find that exposure to a sequence in which the majority of faces are angry depresses probability learning, and that prior exposure to varying quantities of angry and happy faces affects our later memory for them. Overall, there is evidence that exposure to emotional expressions may affect other (selected)c ognitive processesd ependingu pon which expressionsa re used and which experimental methods are chosen. It is suggested that future investigations would benefit from techniques that describe the temporal profile of an emotional response.

Research objective. Investigation of consistent patterns of the induction of flax morphogenesis process, assessment of genetic and physiological aspects of this process and optimization methodologies. Proposition: 1. MOrphogenesis capacity of flax isolated explants depends on a genotype only, but on a composition of a medium and the cultivar type (fibre flax or linseed)also. 2. Cells of different organs of the same genotype have different morphogenic capacity. 3. Combining hormonal ratio with the affect on explats by exogenic factors enables targeted control of the morphogenesis process in vitro.
Darbo tikslas - ištirti linų morfogenezės proceso indukcijos dėsningumus, įvertinti šio proceso genetinius ir fiziologinius aspektus bei optimizuoti regeneravimo metodikas. Ginamieji disertacijos teiginiai: 1. Linų izoliuotų eksplantų morfogeninė galia priklauso ne tik nuo genotipo, maitinamosios terpės sudėties, bet ir nuo veislės tipo (pluoštiniai ar sėmeniniai). 2.To paties genotipo skirtingų organų ląstelės turi skirtingą morfogeninę galią. 3.Derinant hormoninį balansą su eksplantų paveikimu egzogeniniais veiksniais galima kryptingai valdyti morfogenezės procesą in vitro.

My work has involved the investigation of physical and physiological issues related to submarine escape and rescue, including animal experiments using goats, human experiments,engineering and equipment based trials and also the development of a number of mathematical models for the prediction of equipment performance and physiological aspects of decompression. In addition to my published papers I have authored or made substantial contribution to over sixty reports funded by the United Kingdom Ministry of Defence (UKMoD). Experiments in which I made significant contribution in terms of original conception, design, data acquisition and analysis have provided evidence for the efficacy of surface oxygen as a treatment for decompression illness following submarine tower escape and demonstrated that breathing raised partial pressures of carbon dioxide in a distressed submarine then switching to diving quality air in the escape tower is not likely to prevent successful escape. The submitted work demonstrates an advance in our knowledge of the risks of decompression illness and a substantially improved level of confidence in the predictions of mathematical models of decompression illness for submarine tower escape. These are the first semiempirical probabilistic models of decompression illness to combine animal and human decompression illness data using body mass as a scaling factor. Provision of more detailed information on risks of decompression illness and likely outcomes has allowed me to argue for a change in escape policy which has been accepted by the UK Royal Navy (RN). My suggestions for optimising tower escape are to be tested on board UK submarines in the future, prior to possible adoption by the RN. The iso-risk curves I developed for probability of decompression illness and predicted probability of survival following submarine escape have been included as advice in the latest update to ATP-57, the NATO submarine search and rescue manual.

京都大学
新制・課程博士
博士(工学)
甲第23219号
工博第4863号
京都大学大学院工学研究科分子工学専攻
(主査)教授 田中 庸裕, 教授 近藤 輝幸, 准教授 菅瀬 謙治, 教授 佐藤 啓文
学位規則第4条第1項該当
Doctor of Philosophy (Engineering)
Kyoto University
DGAM

The pattern of production, development and survival of component tillers of spring barley (Hordeum distichum) cv. Triumph was investigated. Tiller appearance followed a well-defined pattern, with the emergence of the main shoot followed by that of primary tillers and by higher order tillers. The earliest emerged tillers survived the longest and contributed the largest percentage to grain yield; many of the higher order tillers died prematurely with those surviving contributing little to the grain yield of the whole plant. Tiller death and suppression of tiller production were coincident with the reproductive phase of main shoot development; some late tillering after anthesis was observed. The nutritional and hormonal control of tillering was investigated by applying a range of nutrient and plant growth regulator treatments. Pre-tillering applications of the growth retardant, Terpal, rapidly diminished the growth of the main shoot stem, leaves and roots whilst displaying a promotory effect on tillering. Terpal increased the production and early outgrowth of higher order tillers enabling a greater proportion of these to survive and produce ears; this did not result in any overall increase in yield as mean ear size was reduced. Another growth retardant, Cerone, and the auxin-antagonist, TIBA, similarly promoted tillering. The control of apical dominance systems in uniculm and tillering varieties of barley and wheat were compared. Tiller buds were revealed in the leaf axils of young uniculm plants and in barley it was impossible to initiate their outgrowth whereas several treatments, notably Terpal, Cerone and TIBA promoted tiller production in the uniculm wheat plants. These results are discussed with respect to competition for assimilates/nutrients and the roles of endogenous ethylene, auxin, gibberellins and cytokinins. The possibility of using growth regulators to modify tillering on a commercial scale is discussed and the prospect of seed treatment as a useful method of growth regulator application is also considered.

Diese Habilitationsschrift konzentriert sich auf die Evolution osteologischer Korrelate, anhand derer Rückschlüsse auf die Struktur der Haut sowie die Art der Atmung und der Nahrungsaufnahme früher Tetrapoden gezogen werden können. Die äußere Skulptur der Hautknochen früher Tetrapoden trug zur Konsolidierung der darüber liegenden Dermis bei; dies und die zahlreichen Hautverknöcherungen deuten darauf hin, dass Hautatmung im Gegensatz zu heutigen Lissamphibien keinen wesentlichen Teil des Gasaustausches ausmachen konnte. Es wird die Hypothese aufgestellt, dass eine weitere Funktion der Knochenskulptur in der Pufferung von CO2-induzierter Azidose bestand, wenn sich die Tiere an Land aufhielten. Mehrere Gruppen früher Tetrapoden entwickelten unabhängig voneinander Osteoderme im Rumpf, die unter anderem die Wirbelsäule bei der Fortbewegung an Land unterstützen konnten oder als Kalzium-Reservoir dienten. Die Veränderungen in der Morphologie, Histologie und Anordnung der Dermalschuppen während des Fisch-Tetrapoden-Überganges erfolgte etwa simultan zur Entwicklung der Tetrapodenextremität und ermöglichte eine größere Flexibilität des Körpers und der Beine. Der Bau des Kiemenskeletts ihrer Fischvorfahren wurde bei einer unerwartet großen Anzahl früher Tetrapoden beibehalten. Dies zeigt, dass viele frühe Tetrapoden sowohl der Stamm- als auch der Kronengruppe als Adulte über innere Kiemen atmeten, während ihre Larven äußere Kiemen besaßen. Das Kiemenskelett und die Rekonstruktion assoziierter Muskeln zeigen, dass viele aquatische frühe Tetrapoden ihre Nahrung durch akinetisches Saugschnappen erbeuteten. Trotz spärlicher Fossilüberlieferung gibt es Hinweise darauf, dass die ersten an Land fressenden Tetrapoden noch keine bewegliche Zunge besaßen. Ein ontogenetischer Umbau des larvalen, kiementragenden Kiemenskelets in einen zungenstützenden Apparat kann bei frühen Tetrapoden nur in Ausnahmefällen belegt werden.
This habilitation thesis focuses on the evolution of skeletal correlates from which the integumentary structure and the mode of breathing and feeding in early tetrapods can be inferred. Sculpture on the external surface of dermal bones contributed to the consolidation of a dense integument; this and numerous dermal ossifications render substantial cutaneous respiration as in extant lissamphibians unlikely. It is hypothesised that a further function of dermal bone sculpture was to buffer CO2-induced acidosis while the animals were on land. Numerous early tetrapods independently developed osteoderms in the trunk that may have served among other things for support of the vertebral column in terrestrial locomotion or as a physiological calcium reservoir. The alterations in morphology, histology and arrangement of dermal scales during the fish-to-tetrapod transition occurred at roughly the same time when digits appeared and enabled greater flexibility of body and limbs. The structure of the hyobranchium of their fish-like ancestors was retained in an unexpected large number of early tetrapods, showing that many early tetrapods of both the stem- and crown-group breathed via the associated internal gills as adults, and via external gills as larvae. The hyobranchial apparatus and reconstruction of the associated musculature indicate that many aquatic early tetrapods fed by akinetic suction feeding. There is evidence that the earliest terrestrial tetrapods captured prey on land by jaw prehension rather than by tongue based feeding. Ontogenetic remodelling into a tongue supporting adult hyobranchium in early tetrapods can only be demonstrated in exceptional cases.

The brain areas required for latent learning in the rat are not currently understood. Previous tasks used to assess latent learning, defined as the acquisition of neutral information that does not immediately influence behavior, have shared characteristics that prevented their use to determine the neurobiology of latent learning. This thesis describes a new task called the Latent Cue Preference (LCP) task, derived from the Conditioned Cue Preference (CCP) task that has been successfully used to determine the brain areas required for conditioning in the rat and other animals. In the LCP task, water deprived rats alternately drink a salt solution in one distinctive compartment of a CCP box apparatus and water in the other compartment over 8 days (training trials). They are then given a choice between the two compartments with no solutions present (preference test). The results of the behavioral experiments showed that this training results in two parallel forms of learning: (1) latent learning of an association between salt and salt-paired compartment cues, and (2) conditioning to water-paired compartment cues. Latent learning itself involved two components: (1) the latent association between salt and salt-paired cues, and (2) motivational information about salt deprivation used to retrieve the latent association, and used to compete with the conditioning to water-paired cues. In addition, the findings showed that latent learning and conditioning involve different neural circuits. Latent learning required an intact cortical-to-hippocampus circuit via the entorhinal cortex, while conditioning required an intact subcortical-to-hippocampus circuit via the fimbria-fornix. The acquisition and storage of the latent association depended on an intact entorhinal cortex/dorsal hippocampus circuit, while the use of motivational information to retrieve the association recruited the ventral hippocampus. Conditioning, on the other hand, required an intact fimbria-fornix, lateral amygdala, and hippocampus. These findings provide new knowledge to the field of learning and memory research, and allowed an update of the current Multiple Memory Systems model.

Objectives. The purpose of this study was too determine whether there were significant kinematic differences between recreational and elite hockey players and between contra-lateral lower limbs during forward hockey skating.
Methods. While skating on a hockey treadmill subjects were filmed with four synchronized digital video cameras while wearing reflective marker triads on the thighs, shanks and skates. Subjects skated within a calibrated volume at a self selected speed that they could maintain comfortably for one minute. Each subject completed three trials separated by 5 minutes of rest. Data was reduced and analyzed using programs written in MATLAB. Two-way ANOVA and Tukey Post Hoc tests were used to determine statistic significance.
Results. Elite and recreational subjects were significantly different (p≤0.05) during knee abduction and knee rotation at push off, as well as during knee abduction and knee flexion at blade contact. Contra lateral lower limbs were significantly different (p≤0.05) during ankle abduction and hip rotation at blade contact as well as during knee abduction at push off.
Conclusion. Some aspects of the skating stride are similar in elite and recreational hockey skaters but there were several kinematic differences between skill levels and contra-lateral legs. The skating kinematics of elite hockey players may serve as a model for young hockey players and recreational hockey players, helping them develop a more efficient and effective stride.

Despite similar rates of energy expenditure during training, competitive swimmers have been shown to store significantly greater amounts of body fat than competitive runners. In an attempt to explain these discrepancies, male collegiate swimmers (n=8) and runners (n=8) were monitored during 45 min of swimming and running, respectively (75% V02 max), and during two hours of recovery. In addition, a group of male competitive triathletes (n=6) were similarly monitored during and after both swimming and running exercise.Blood samples were obtained after 15 min rest prior to exercise and at 0, 15, 30, 60 and 120 min of recovery and were analyzed for glucose, lactate, glycerol, free fatty acids, insulin, glucagons, norepinephrine (NE) and epinephrine (E). Respiratory gases were collected at 15 min intervals during exercise and at 15, 30, 45, 60, 90 and 120 min of recovery. Heart rate and mean body temperature were recorded at 10 min intervals throughout recovery. There were no differences in post-exercise oxygen consumption or heart rate while the RER suggested increased fat oxidation after exercise for the swimmers and the swimming triathletes. The mean body temperature and mean skin temperatures were significantly lower throughout 120 min of recovery for the swimmers compared to the runners. The triathletes demonstrated a similar tendency but these differences were not significant. The serum glucose levels were significantly greater (P<0.05) immediately post-exercise for the runners compared to the swimmers (6.71 +0.29 and 4.97 +0.19 mmol•1-1, respectively). Blood glucose values were also significantly greater immediately post-run for the triathletes (6.40 +0.26 and 4.87 ±0.18 mmol-l-1 for running and swimming, respectively). Blood glucose values remained elevated for runners and the running triathletes up to 30 min of recovery. Free fatty acids were similar after the run and the swim, but glycerols were increased immediately after running in the runners (P<0.05) and the triathletes (P<0.05). Differences in blood glucose levels or fat release were not explained by differences in NE, E or cortisol. The glucagon-to-insulin (G:I) ratio was significantly increased after exercise in the swimmers and the swimming triathletes. This, combined with a reduced RER after the swimming trials, suggests that the reduced glucose levels were due to reduced hepatic glycogen stores. The results of this study suggest that there were differences in substrate utilization during running and swimming exercise of the same intensity. These differences were not explained by NE, E or cortisol; however, the increased G:T ratio suggests increased carbohydrate use during exercise in the swimmers. Finally, body fat differences between runners and swimmers were not explained by differences in post-exercise energy expenditure or fat oxidation.

Although upper respiratory tract infections (URTI) are the most frequent illness among humans, insufficient evidence exists to determine if exercise training during an URTI may prolong or intensify an URTI. The purpose of this investigation was to determine the effect of exercise training on the severity and duration of URTI symptoms. Following serological screening, those subjects who were rhinovirus 16 (RV 16) antibody-free completed a graded exercise test. Thirty-four individuals (ages 18-29 years) of moderate fitness (between 32 ml/kg"1/miri 1- 60 ml/kg 1/min"1) were randomly assigned to the exercise group (EX) while 16 individuals of similar age served as a nonexercise control group (CTL). All subjects were inoculated with RV 16 on two consecutive days. EX subjects completed 40 minutes of supervised exercise at 70% of heart rate reserve within 18 hours of each inoculation and then exercised every other day for the next eight days (total of six exercise sessions). Immediately following each exercise period subjects completed a symptom checklist. EX subjects were strongly encouraged to abstain from any additional physical activity while the CTL group was encouraged to be as sedentary as possible for ten days beginning the first day of inoculation. Prior to the first inoculation and every 12 hours afterwards all subjects completed a 13 item symptom severity checklist and a physical activity log (e.g., minutes of walking, and hours of work). Used facial tissues were collected and weighed during these same reporting periods. One-way analysis of variance indicated that there! was no significant difference between groups with respect to additional physical activity. Two-way analysis of variance indicated that there were no significant differences in either the severity or duration of an URTI (symptom scores, mucous weights) between the EX and CTL groups for any given day. Further, no significant differences were observed between the pre and post exercise symptom scores for the EX group. These results suggests that moderate exercise training during a rhinovirus-caused URTI does not appear to alter the severity and duration of the illness. This was the first study to examine the influence of exercise on symptom severity and duration during an URTI. Additional studies should be performed utilizing various exercise prescriptions (e.g. intensity, frequency and duration), subject populations (e.g. younger and older), and fitness levels (e.g. sedentary, and highly fit).
School of Physical Education

The purpose of this study was to determine the effects of an upper respiratory illness (URI) on running mechanics during a maximal VO2 exercise treadmill test. The specific measurements assessed were stride length (SL), stride frequency (SF), range of motion (ROM) of the hip, knee, and ankle, and the displacement of the center of mass (COM) during the stride cycle. Fifty-three subjects (female=25, male=28) between 18 and 30 years of age completed the study. The participants in the study were characteristically non-smokers, drank fewer than five alcoholic drinks per week, had no orthopedic problems, were not pregnant, did not suffer from hay fever or chronic colds, and were not allergic to penicillin. Rhinovirus Type 16 was used in the inoculation of the individuals. The subjects performed two maximal V02 treadmill test. The first test was before the inoculations and the second test was during the height of the illness. Stride length and SF data were derived from accelerometer data. Statistical analysis using ANOVA revealed no significant changes in SL or SF between pre- and post-inoculation treadmill tests. Based on the results of this study it was concluded that Rhinovirus Type 16 does not effect running mechanics during a maximal V02 treadmill test.
School of Physical Education

Viral illnesses are the most common agents affecting humans. Due to their widespread affects, viruses may have a particular influence on exercise functional capacity. Therefore, the purpose of this study was to determine the impact of an Upper Respiratory Infection (URI) on exercise functional capacity, as measured by VO2max. In addition, submaximal exercise responses, changes in resting pulmonary function, the impact of select symptoms, and level of initial fitness on performance during an URI were also determined. Forty-five subjects (females=21, male=24) between 18 and 29 years of age participated in this study and were assigned to a mild or severe illness group based on symptom severity. There was also a control group of 10 subjects (female=5, male=5). An initial serological screening was performed on all experimental subjects to assess for the RV16 antibody.Subjects testing negative for the antibody performed a baseline graded exercise test to volitional fatigue, as well as pulmonary function tests. Each subject was inoculated two consecutive days with the RV16 virus within ten days of the baseline exercise test. The day following the second inoculation (peak illness) the subjects performed post-pulmonary function and exercise tests. The control subjects performed two resting pulmonary function and exercise tests separated by one week. Significance was set at p<0.05. Repeated measures ANOVA revealed a significant interaction in V02 at submaximal and maximal levels between trials for all groups (p<0.045). A significant interaction for VE for all levels and all groups was found (p<0.002). No impairment in resting pulmonary function was observed. Analyses of symptoms, and initial V02 in regard to performance, also revealed no significant differences. Therefore, the results seem to indicate that an URI does not limit one's ability to perform at submaximal or maximal levels of exercise, however, some relationship seems to exist. Further research is needed to clarify the effects of an URI on physical performance.
School of Physical Education

The present investigation was designed to elucidate the potential influence of age on speech breathing. Toward this end, 30 men representing three widely different age groups (25, 50, and 75 years) were studied. These individuals were carefully selected to meet stringent criteria, the most important of which related to health and physical characteristics. Speech breathing was studied via anteroposterior diameter changes of the rib cage and abdomen. Recordings were made during extemporaneous speaking and reading and during the performance of various chest wall maneuvers used in the measurement of the speech breathing data. In addition to speech breathing, selected measures of general respiratory function were obtained. These included measures of subdivisions of the lung volume and measures of resting tidal breathing. Results indicated that these 30 subjects were representative of other subjects studied with respect to measures of general respiratory function. Subdivisions of the lung volume were found to differ with age in the manner predicted by previous investigations. Age-related differences were most marked for measures of vital capacity and residual volume. By contrast, there were no age-related differences for measures of resting tidal breathing. Several speech breathing measures were found to differ with age. Age-related differences were usually between the 25- and 75-year-old subject groups and less commonly between the 25- and 50-year-old subject groups. For extemporaneous speaking, differences were found for lung volume excursion, rib cage volume initiation (referenced to the rib cage volume associated with the relaxed configuration of the chest wall), number of syllables per breath group, and lung volume expended per syllable (in percent vital capacity). For reading, differences were found for lung volume expended per syllable (in percent vital capacity). Age-related similarities and differences in general respiratory function and speech breathing are discussed in relation to possible underlying mechanisms. In addition, implications are drawn regarding evaluation and management of individuals with speech breathing disorders.

The purpose of this study was to investigate the effects of trumpet playing upon the heart. A Holter monitor was used to record electrocardiograms (ECGs) to examine the heart's response during musical performances and practice sessions.

In order to test the effect of artificially induced alkalosis and acidosis on the appearance of blood lactate and work production, six well-trained oarsmen (age= 23.8 ±2.5 wt = 82.0 ±7.5kg.) were tested on three separate occasions after ingestion of 0.3 gm/kg body wt. NH4C1 (acidosis) , NaHC03 (alkalosis) or a placebo (control). Blood was taken from a forearm vein immediately prior to exercise for determination of pH and bicarbonate (HC03). One hour following the ingestion period, subjects rowed on a stationary ergometer at a pre-determined sub-maximal rate for 4 minutes, then underwent an immediate transition to a maximal effort for 2 minutes. Blood samples from an indwelling catheter placed in the cephalic vein were taken at rest and every 30 seconds throughout the 6 minute exercise test, and every 3 minutes during a 30 minute passive recovery period. Pre-exercise blood values demonstrated significant differences (p<0.01) in pH and HC03 in all three conditions. Work outputs were unchanged in the submaximal test and in the maximal test (p>0.05), although a trend toward decreased production was evident in the acidotic condition. Analysis of exercise blood samples using ANOVA with repeated measures revealed that the linear increase in blood lactate concentration([BLA]) during control was significantly greater than acidosis (p<0.01), although [BLa] during alkalosis were consistently elevated above control there was no significant difference in the linear trend (p>0.05). During recovery, there was no significant difference in the rate of lactate disappearance amongst the three conditions. It was concluded that under this protocol artificial manipulation of the acid-base status of the blood does not significantly influence work production despite significantly reduced [BLa] during acidosis. The inability of these pH changes to alter exercise performance emphasizes the relative importance of the intracellular and the extracellular buffer systems in well trained athletes.
Education, Faculty of
Curriculum and Pedagogy (EDCP), Department of
Graduate

The purpose of this study was to establish an exercise protocol that demonstrated a relationship between rest-interval duration and the exercise induced human growth hormone (hGH) response. Ten recreationally trained male subjects (23 ± 0.9 yrs) performed three leg extension trials on an Eagle — Cybex leg extension machine that consisted of 4 sets of 10 repetitions. The workload and volume was kept constant, but each trial had different rest-interval durations. Rest-interval durations between sets were at: 30 sec intervals (T-30), 60 sec intervals (T-60), or 120 sec intervals (T-120). Blood samples were obtained pre- and 0 — 30 minutes post-exercise and analyzed for lactate and hGH. All blood lactates rose significantly above baseline after exercise, with no differences in time of occurrence between trials. Blood lactates were significantly greater after the T-30 trials, compared to that of the T-60 and T-120 trials. There was no significant difference in hGH concentrations between trials. However, the data did suggest a relationship between rest-interval duration and the variability of hGH responses. The T-30 trials yielded significantly greater variation in hGH concentrations than the T-120 trials, and the T-120 trials showed significantly less variation than both the T-30 and T-60 trials. Although significant differences were found in these variations between trials, they did not prevent any significant differences in concentrations between trials from being found. In summary, the results of this study demonstrated an exercise related increase in lactic acid that had an inverse relationship to the length of the rest-intervals. hGH data on the other hand, did not show a relationship between rest-interval duration and the hGH concentrations. The connection between rest-interval duration and variability of hGH responses could possibly suggest that hGH values may have been significantly different if an exercise protocol higher in volume were utilized. Additionally, the results indicate that there is no direct relationship between blood lactate and hGH concentrations, as others have suggested.
School of Physical Education, Sport, and Exercise Science

Twenty-four anxiety disorder subjects. 12 simple phobics and 12 panic disorders with agoraphobia, were assessed for physiological response (SCL, HR and EMG) to phobic imagery scripts. Subjects were instructed to image during tape-recorded scripts of standardized neutral (Neutral) and personally relevant fear (Phobic) scripts. All scripts contained both stimulus and response cues; however, subjects were presented four versions of a script which varied in response cue (propositional) content and presentation style: a version presented non-interactively which contained no cognitive cues (meaning propositions), a version presented non-interactively which contained cognitive cues, a version presented interactively which contained no cognitive cues, and a version presented interactively which contained cognitive cues. Both diagnostic groups produced significantly increased HR and SCL in response to Phobic scripts which contained cognitive cues and were presented interactively. Phobic Scripts which contained cognitive cues and were presented non-interactively produced significantly increased arousal only in the panic disorder group as measured by HR. Simple phobics also responded with significantly increased SCL to Phobic scripts presented interactively with no cognitive cues. Neither diagnostic group responded with increased arousal to the Phobic script presented non-interactively with no cognitive cues. Contrary to previous research, these results indicate that subjects with panic disorder with agoraphobia are capable of producing significantly increased physiological arousal in response to phobic imagery. The crucial importance of imagery script content and presentation style are highlighted by the results. Furthermore, the current investigation differed from previous investigations in that the parameters of an actual therapy session were more closely approximated by having the subjects image during script presentation rather than subsequent to script presentation. Finally, frontalis EMG did not prove to be a sensitive measure of anxiety in these subject populations pointing to the need for multiple channels of physiological measurement. Implications for content and methodology of future research studies in this area are discussed.
Ph. D.

The purpose of this study was to examine the effect of swimming distance and rest interval on the intensity of swimming (relative to VO2 max) and the contributions of the three energy systems (aerobic, anaerobic, and alactic) during these interval sets. Nine male college swimmers performed fourteen different interval training sets. Distances were 25, 50, 100, or 200 yards with rest intervals of 10 seconds, 1, and 3 minutes. During these sets only the distance to be swum and the rest interval for the set was given. No qualitative information from the coach was provided. These interval sets were performed by the swimmers with the influence from timers being kept minimal. Oxygen cost during the swim was determined from the velocity of the swim based on a linear regression for swimming velocity and oxygen uptake for each swimmer. The same interval sets were completed with pace controled where venous blood samples were obtained 1, 3, 5, and 7 minutes after the completion of each training set. 81ood samples were analyzed for lactate accumulation, blood pH, p0.,, pCO2, and hemoglobin. From these values bicarbonate, base excess, and blood oxygen saturation were calculated using equations developed by Siggard-Anderson. The results of this study do indicate that there is a predictable relationship between swimming distance and rest interval on swimming intensity (relative to VO., max). There was a curvilinear L relationship between swimming intensity (relative to VO max) and rest interval for 50, 100, and 200 yard interval sets. The correlation at these distances were r-0.96, 0.93, and 0.94 respectively. There was a linear relationship between intensity and the distance swum for the 10 second, 1, and 3 minute rest intervals. The correlation for these rest intervals were r= 0.99, 0.99, and 1.00 respectively. There was an increase in the relative contribution of aerobic energy as the distance of the swim increased for all three rest intervals. At a given swiming distance there was a greater contribution of non-aerobic energy as the rest interval increased. Contrary to continuous swimming, greater swimming velocity does not directly correspond to greater contributions of anaerobic energy during intermittent swimming. The distance and rest interval during intermittent training greatly effect the relative contributions of the three energy systems. The intensity of the swim and the relative contributions of each energy system should be considered when planning specific training regimens.

The present study sought to determine the influence of environmental conditions and protective clothing on physiological, perceptual and performance responses during batting activity. The investigation examined mean skin temperature, average heart rate, estimated sweat rate, rating of perceived exertion, thermal sensation rating, average sprint time and pre-post choice reaction time. Twenty-five cricketers (18-22 yr, 73.1 ± 9.6 kg, 1768 ± 75 mm, 12.6 ± 3.1% body fat, 1.89 ± 0.16 m2) performed a work-bout consisting of a seven-Over batting period, during which time they faced deliveries from a bowling machine and performed two shuttle runs every third ball to total four sprints per Over. Trials were carried out under High-stress (23.8 ± 2.2 °C) and Low-stress (13.3 ± 1.9 °C) environmental conditions (WBGT). Within each environmental condition subjects performed the test wearing full protective batting gear and no protective gear. Thus, four specific conditions were examined; high full-gear (HFG), high no-gear (HNG), low full-gear (LFG) and low no-gear (LNG). Two-way ANOVAs were calculated to determine whether there were differences between environmental conditions and whether differences existed between the clothing conditions. One-way ANOVAs were utilised to compute differences between the four specific conditions combining clothing and environment. High environmental stress and wearing protective clothing caused batsmen to experience significant physiological strain. The environment was the greatest stressor, with the protective gear exacerbating these effects. However, when padding covered skin areas directly, this was the primary skin temperature stressor, particularly later in the activity. For skin temperature and heart rate, the strain was the most pronounced at the end of the trials. Perceptual responses indicated that the protective gear had no influence on effort sense, thermal sensation or thermal comfort. However, environmental conditions had an effect, and High-stress conditions resulted in significantly higher perceptions of effort, elevated sensations of heat and greater thermal discomfort. Effort was perceived to be greatest towards the end of the trial. There were mixed findings for performance factors. In general sprint performance was not hindered by environmental stress, but protective clothing caused a reduction in several sprint times. Choice reaction times were for the most part unaffected by either environment or clothing and few differences were observed between pre and post times. It is contended that intense short duration batting activity, likely encountered during one-day participation, imposes a stress on batsmen. The stress is greater when conditions are warmer and protective padding is worn, although it is not sufficient to impede choice reaction time. However, protective gear did have a deleterious effect on sprint performance.

The purpose of the present study was to investigate a human being's basic responses to being touched by another human being in a nonreactive context and the effects of an illogical rationale on system disorganization. Two hypothesis were put forth: 1 - that persons in similar circumstances who are not touched, and 2 - that persons who are touched for a reason that makes sense will display less psychological and physiological variability than persons who are touched for a reason that makes less sense or, perhaps, is even considered "illofical." Forehead touch was chose. Positive and negative affect scales were utilized to measure psychological reactivity while skin temperature and heart rate were employed to measure psychological reactivity. These hypotheses were not supported in the present study since the expected group by phase interactions were not obtained. Instead, main effects for phase were found, especially for heart rate scores. Many concerns about the nature of the sample and the manipulation itself are discussed.

Background: Despite the introduction of running footwear in the 1970’s, running injury rates continue to be unacceptably high. The subsequent revival of barefoot running and the introduction of minimalist footwear occurred, in an attempt to reduce injury rates and increase performance. There is much contention in the literature around the effectiveness of these footwear conditions. Furthermore individual responses have recently been proposed to provide more accurate and reflective conclusions than the use of mean data. Objectives: Twofold: a) to compare the biomechanical, physiological and perceptual responses between the shod, minimalist and barefoot footwear conditions and b) to assess and compare individual responses under these footwear conditions. Methods: 26 well-trained, male, habitually shod endurance runners, aged between 18 - 30 years completed three experimental sessions on an indoor runway and motorized treadmill. Each session was completed in either the shod, minimalist or barefoot condition, running at 15km.h-1. Variables assessed included stride rate, stride length, impact peak, vertical impact and average loading rate and strike time (biomechanical); heart rate, oxygen consumption and electromyography (physiological); and rating of perceived exertion and body discomfort (perceptual). Results: Biomechanics – Stride rate and stride length showed a significant (p<0.001) increase and decrease respectively when running in the minimalist or barefoot conditions versus shod. Running barefoot versus the minimalist and shod conditions resulted in a significantly (p<0.001) greater vertical impact loading rate. Strike time was significantly (p=0.008) reduced running in the minimalist and barefoot conditions versus shod. Physiology – Running barefoot versus shod resulted in a significantly (p=0.02) reduced heart rate and Tibialis Anterior activity (p=0.005). There was a large variability in individual responses for many variables, with responders and non-responders seen. Conclusion: The study suggests that there are significant differences between all three forms of running for some variables. It was further noted that there is support for the proposal that individual responses are highly variable and should be analysed accordingly

The purpose of this study was to examine the participants of the Ball State University Retirees Fitness (BSURF) program in order to determine the role that habitual participation in an exercise program plays on the aging process. The participants of the BSURF program were divided into two groups: those that have been exercising for seven or more years (LT; n=14), and those that have been exercising for six years or less (ST; n=10). Subjects underwent testing on the following variables: BMI, body composition, resting heart rate and blood pressure, blood lipid profile, biceps muscular strength, trunk flexibility, and the Rockport Walk Test. Group differences were determined using an independent t-test. Despite a significant difference in age and duration of participation time between the LT and ST groups, no statistically significant differences in cardiovascular measurements, anthropometric measurements, and body size were seen between the two study groups. The only exception to the positive effects of this exercise program on the aging process is demonstrated by the trunk flexibility data. The ST group was significantly more flexible (27.6 ± 1.51 cm) than the LT group (17.7 ± 2.67 cm). The results of this study suggest that continued participation in the BSURF program enabled the LT group to maintain their physiological functioning. Further, the length of participation by the members of the BSURF program clearly demonstrates significant adherence, and suggests that a program of moderate intensity in combination with a large social aspect may play a role in the exercise adherence of older adults.
School of Physical Education