PHD-School of Applied Human Sciences

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This collections contains bibliographic information and abstracts of PHD theses and dissertation in the School of Applied Human Sciences held in Kenyatta University Library

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Browsing PHD-School of Applied Human Sciences by Author "Boit, Michael K."

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    Assessment of Pulmonary Function of Kenyan Elite Distance Runners during Rest, Sub-Maximal and Maximal Endurance Exercise
    (2014-02-22) Mwangi, Francis Mundia; Onywera, V.O.; Boit, Michael K.; Sheel, W.
    Kenyan middle and long distance runners have performed extraordinarily well, dominating the world over the past four decades. The factors that contribute to their prowess in endurance races are not yet determined. Pulmonary limitations to endurance performance have been reported among non-Kenyan runners but the extent Kenyan runners experience or overcome these limitations had not been investigated. The purpose of this study was to assess pulmonary function parameters of Kenyan elite runners in relation to endurance exercise performance and compare with predicted values. Fifteen (10 male, 5 female) purposively selected elite Kenyan runners were instrumented in baseline spirometry and an incremental treadmill test to exhaustion at a moderate altitude (1,600 m.a.s.l.). Spirometric variables measured included forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory volume in one second as a proportion of forced vital capacity (FEV1/FVC) and maximum inspiratory pressure (MIP). Respiratory measures obtained during treadmill test included tidal volume (Vt), breathing frequency (Fb), minute ventilation (VE), oxygen consumption (VO2), carbon dioxide production (VCO2) and respiratory exchange ratio (RER). Arterial blood gases (ABG) data; arterial oxygen partial pressure (PaO2), arterial oxygen saturation (SaO2), arterial partial pressure of carbon dioxide (PaCO2), alveolar to arterial oxygen partial pressure difference (A-aDO2) and acidosis (pH) were obtained from blood samples taken from radial artery at the end of every exercise stage via indwelling cannula. Repeated measures ANOVA and t tests were run to examine the various measurements at different exercise intensities using statistical package for social sciences. One sample t test on participants’ spirometric variables’ percentage of predicted values showed that they were not significantly different from commonly used predicted values (p >.05). Absolute VO2 peak values for males (3.50±.26) and females (2.26±.26) [L/min] were significantly higher than the predicted values (p = .001). Relative VO2 max formales (64.4±4.9) and females (48.1±4.9) [ml/kg/min] rated superior and excellent respectively on cardio-respiratory fitness classification norms. ABG data showed that the runners experienced only moderate levels of exercise-induced arterial hypoxemia (EIAH) (SaO2 = 89.4±4.6%[male], 91.5±2.2%[female], 89.9±4.1[total]% and A-aDO2 = 24.5±4.7[male], 20.1±10.7[female], 23.39±6.39[total] mmHg) at maximal endurance exercise. Respiratory compensation (partial) for metabolic acidosis was evident (PaCO2 = 34.15±3.44 mmHg, pH = 7.30±.08[total]). Bicarbonate ions (HCO3) recorded the most consistent decline and highest effect size (Eta sqd = .724) while change in oxygen content in the blood (CaO2) recoded the least (Eta sqd = .072). Stepwise regression showed that VE was the most significant predictor of VO2 and speed at sub-maximal exercise level. The study concluded that most Kenyan distance runners’ baseline pulmonary function values are comparable to commonly used reference values. However, the runners’ respiratory system is able to cope with demands of superior oxygen consumption during endurance running. The runners experience moderate level hypoxemia during sub-maximal and maximal endurance exercise. Strategies to alleviate excessive acidosis are recommended for improving performance during endurance training and competitions. Further investigations are needed to determine the source of the differences in pulmonary function among distance runners, and the effects on endurance race performances.
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    Evaluation of the professional preparation and certificate of athletics coaches in Kenya
    (2011-12-07) Mwisukha, A.; Simiyu, N.W.W.; Wamukoya, Edwin K.; Boit, Michael K.
    The present study evaluated the professional preparation and certification of athletics coaches in Kenya. The variables of the study included scrutiny of the coaches' gender, age, marital status, level of education, other employment; areas of coaching, nature and level of training, course content, duration of courses, competency of coaches' instructors, assessment of trainee coaches, frequency of refresher courses and availability of coaching literature. Other variables included the adequacy of athletics coaches' education, their level of effectiveness, professional training needs and problems. Data were gathered from 229 respondents who included provincial and national executive officials of Athletics Kenya, government sports officers and coaches. Questionnaires were used to gather data. The data were analyzed using descriptive statistics, while hypotheses were tested using Chi-square test and Spearman rank order correlation coefficient. The results indicated that majority of the coaches were males, and were married. The largest proportion of the coaches possessed ordinary level of education, and had other regular permanent occupations besides their coaching roles. The coaches for middle and distance runners outnumbered those for sprints and field events. The International Association of Athletics Federations trained most of the athletics coaches. The main content area of the coaches' courses was Theory and Practice of Athletic Techniques and Tactics, but sport psychology received least attention. A larger fraction of the coaches indicated that the duration of the courses was adequate. Most coaches acknowledged that theory and practical examinations were administered during their coaching courses. Although many coaches viewed their course instructors as competent, the analysis of their views on the basis of their academic qualifications yielded a X2 of 76.94 (p< 0.05). The coaches indicated that their access to coaching literature was infrequent as their ratings on this variable on the basis of their academic qualifications produced a X2 of 8.10 (p> 0.05). In spite of the finding that many of the coaches, government sports officers and Athletics Kenya (AK) officials indicated that coaching and in-service courses were infrequent, their views yielded a x2 of 18.34 (p<0.05). Majority of the three groups of respondents indicated the need to train more coaches in sprints, middle and long distance races, and field events, with their views producing X2 values of 3.21 (p>0.05), 5.45 (p>0.05) and 2.32 (p>0.05) respectively. There were significantly positive correlations, rs = 0.72 (p<0.05) and rs = 0.57 (p=<0.05) between the coaches' and managers' views with regard to the training needs and problems of athletics coaches, respectively. Their main need and problem is regular in-service courses and inadequate finances, respectively. On the overall, the three groups of respondents indicated that the training of the coaches was inadequate, as their views yielded a X2 of 9.37 (p>0.05. The inadequacy of training was attributed to insufficient course content, limited access to in-service courses and coaching literature. It was therefore, recommended that AK and the Ministry of Gender, Sports, Culture and Social Services should establish a centralized institution to standardize and conduct frequent athletics coaching and in-service courses to meet coaching personnel needs in the country. AK and the government should set up learning resource centres across the country where coaches can access recent coaching literature. An athletics coaches' licensing board should be formed to ensure high standards in coaching and offer licenses to qualified coaches only. AK and the government should find alternate ways of raising funds to cater for the training of coaches.
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    The female athlete triad profile of elite Kenyan runners and its future health implications
    (North-West University, 2014-09) Goodwin, Y.; Monyeki, M.A.; Boit, Michael K.
    The female athlete triad (FAT or the TRIAD) is a complex syndrome arising from associations among the trio of energy availability (EA), menstrual function (MF) and bone mineral density (BMD) along their respective continuums from health to disease state. It has been recognized that women whose energy intake (EI) does not meet the energy requirements for physiological functions subsequent to participation in exercise and physical activity could have low EA. In the TRIAD, low EA, an initiator in menstrual dysfunction (MD) and concomitant hypoestrogenism, indirectly results in low BMD. Therefore, the purpose of this study was to: (i) establish the status of EA, MF and BMD among elite Kenyan female athletes and non-athletes, (ii) explore associations between EA and MF in elite Kenyan female athletes and non-athletes, (iii) determine the relationships of EA and MF to BMD in elite Kenyan female athletes and non-athletes, and (iv) to determine the profile of the female athlete triad in elite Kenyan distance athletes and in non-athletes. Measurements of EA, MF and BMD were undertaken in 39 female participants (Middle distance athletes =12, Long distance athletes=13, Non-athletes=14). Energy intake minus exercise energy expenditure (EEE) and the remnant normalized to fat free mass (FFM) determined EA. Energy availability was determined through weight of all food and liquid consumed over three consecutive days. Exercise energy expenditure was determined after isolating and deducting energy expended in exercise or physical activity above lifestyle level from the total energy expenditure output as measured by Actigraph GT3X+. Fat free mass and BMD were assessed using dual energy x-ray absorptiometry (DXA). A nine-month daily temperature-menstrual diary was used to evaluate menstrual status. In addition, since psychological eating behaviour practice (EBP) contributes to low EA, the Eating Disorder Examination Questionnaire (EDE-Q) was used to determine presence of such practice among the participants and their relationship to EA. Overall, EA below 45 kcal.kgFFM-1.d-1 was found in 61.53% of the participants (athletes=28.07±11.45kcal.kgFFM-1.d-1, non-athletes=56.97±21.38kcal.kgFMM-1.d-1). The ANOVA showed that there was a significant difference (p<0.001) in EA among the long and middle distance runners and non-athletes; and the Tukey‘s HSD revealed that the source of the difference were the non-athletes. Results of the EDE-Q showed almost negligible presence of psychopathological eating behaviour practice among the Kenyan participants. None of the TRIAD components showed significant relationship with EBP. Results of MF showed that whereas none of the athletes presented with amenorrhea, oligomenorrhea was present among 40% athletes and 14.3% non-athletes, and amenorrhea vii among 14.3% non-athletes. However, there was no significant difference between athletes and non-athletes in MF. Low BMD was seen in 76% of the athletes and among 86% of the non-athletes. The analysis did not show significant difference in BMD Z-scores between athletes and non-athletes. The analysis did not show any significant association between EA and MF among the participants. The only significant relation of EA to any BMD dimension measured was between EA and total BMD in the long distance runners (r=0.560; p=.046). Significant relationship (rho=0.497; p=.001) was found between MF and BMD Z-scores among the athletes with middle distance highlighting the relationship further (rho=0.632; p=.027). Overall, the binary logistic regression revealed that MF did not predict BMD (OR=4.07, 95% CI, 0.8-20.7, p=.091). Overall, 10% of the participants (athletes=4, long distance athletes =3, middle distance athletes=1, non-athletes=0) showed simultaneous presence of all three components of the TRIAD. The independent sample t-test showed a significant difference (t=5.860; p=<.001) in the prevalence of the TRIAD between athletes and non-athletes.