Doctoral Degrees (Biokinetics, Exercise and Leisure Sciences)

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Perceived psychological benefits of participation in leisure activities.
(1992) Hudgson, Norma May.; Butler-Adam, Joann Camille Ellis.; Andrews, Barry Craig.
The effects of exercise and diet on selected physiological and biochemical parameters in a sedentary Indian male cohort.
(1995) Coopoo, Yoganathan.; Andrews, Barry Craig.
In common with other expatriate Indian Populations, the Indian community of South Africa has a high incidence of coronary heart disease (CHD). Little information is available on the effects of exercise and diet on risk factors in this group. The present study is directed at the functional changes occurring as a result of a moderate aerobic physical activity programme, comprising 30 minutes of supervised exercise, three times per week for 15 weeks. Healthy male volunteers were recruited from the staff of the University of Durban-Westville, who were not on any lipid lowering medication and were not involved in any programme of physical activity for at least 12 weeks before the start of the project. The 41 subjects were assigned into one of three groups: exercise only (E) (15 subjects); exercise and diet (ED) (14 subjects) and a control (C) (12 subjects) group on no intervention. Besides laboratory investigations all participants were subjected to standardized fitness and anthropomorphological evaluation, a brief family history for coronary artery disease and a detailed dietary history was compiled. Baseline lipid results indicate that only 7 of the 41 subjects had normal lipid profiles using as cut-off points 5.2 mmol/l for cholesterol, 1.5 mml!l for triglyceride and 0.9 mmol/l for HDL-C. Obesity was moderately prevalent before intervention, with a mean decrease of 25% in body fat in both E and BD groups(p~0.05). The experimental subjects became leaner. After the intervention programme an average 20 percent increase was evident in physical working capacity as measured by peak V~ in both experimental groups (p~0.01). The controls showed little variation over the 15 weeks. The indices of muscular endurance and flexibility showed statistically significant changes (P~ 0.05) in both experimental groups after intervention. This certainly indicates elevated levels of fitness after the intervention. The lipid profiles show little alteration in total cholesterol, with a 7.3% decrease in triglyceride levels in the E group (which was not statistically significant) compared with a 14.7% increase in the controls. HDL-C showed an increase in both experimental groups (p~0.01). The total cholesterol to HDL-C ratio had an average fall of 11.9% in the experimental groups (P~0.05) compared with a 5.6% decrease in the control group. These data support the claim that regular, moderate exercise reduces the risk of heart disease through its effects on coronary risk factors in a high risk South African population.
An analysis of perceived leadership styles and levels of job satisfaction of sport administrators employed at tertiary institutions in South Africa.
(2007) Naidoo, Padmini.; Coopoo, Yoganathan.
The leadership role of sport administrators in South Africa is of prime importance as the local sports industry in South Africa is worth in excess of R2 billion annually. The most important variable in explaining sport administrators' success becomes leadership style. Sport administrators' roles are vital to the sporting industry and therefore the degree of job satisfaction they experience is of prime importance. The key objectives of the study were to determine the different styles of leadership available in sport administration departments, to identify factors affecting the progress and status of transformation in sport administration departments, to examine the factors affecting the progress of gender equity at tertiary institutions, to identify factors which influence job satisfaction or lack of it among sport administrators and coaches employed at tertiary institutions and to determine the organizational effectiveness of tertiary institution sport departments. The questionnaire was administered to 300 coaches who had to rate their sport administrators' leadership style and 140 sport administrators. A response rate of 78% (n=109) was obtained from sport administrators and 76% (n=227) were received from coaches. The data were analysed using the computer package SPSS. From the research the following conclusions can be drawn with respect to job satisfaction and leadership among sport administrators and coaches. The overall majority of the tertiary institution sport administrators adopted a transformational style of leadership. There was a lack of transformation in the industry and gender equity in the industry. There were reasonable de grees of satisfaction in the profession, however certain variables were more pronounced than others. The study proposed the following recommendations: Those sport administrators that are still practising a more transactional and laissez-faire approach to leadership should start adopting a more transformational approach to leadership. More females need to be placed in leadership positions at tertiary institution sport departments. With regard to transformation higher management at tertiary institutions should strive to create diversity by employing individuals from other race groups to ensure transformation at institutions of higher learning. This will also serve to rectify the imbalances of our past. Management at tertiary institutions should also strike a balance with regard to gender equity. With regard to improving coaches and sport administrators' job satisfaction higher management needs to adopt a policy of open communication between staff employed at the tertiary institution sport departments and themselves.
Diet and supplementation practice in professional Ethiopian football players : effects on performance and recovery.
(2018) Masho, Tesfaye Berhane.; McKune, Andrew James.; Van Heerden, Jaques Johan.
The game of football places high physiological demands on players, who are expected to react by carrying out a range of physical activities at different intensities. Such movement patterns contribute to a high energy turnover in both training and match-play, which in turn must be sustained by the intake of adequate fuel sources. In this thesis, three studies were undertaken with the intention of gaining greater insight into, and adding to the body of knowledge of, football nutrition in Ethiopia. The studies included an evaluation of the impact of a sports nutrition education programme on the dietary, sports nutrition and supplement practices of the Ethiopian national football squad during the period 2012 to 2014 (Study 1). The dietary intake, sports nutrition and supplementation practices of professional Ethiopian football players currently playing in Ethiopian Premier League clubs (Study 2) were then studied, as well as the relationships between training load, energy balance, performance and recovery (Study 3). Study – 1. Football players require adequate knowledge of nutrition to allow correct selection and consumption of food and fluids to meet their performance, body composition and overall health needs. The aim of this study was to examine the effect of a sports nutrition intervention on the nutrition knowledge and dietary choices of the players who were members of the Ethiopian national football squad between 2012 and 2014. The following sports nutrition topics were discussed: timing of nutrition, recovery, hydration, post exercise physiological perceptions, macronutrients, sports drinks, fruit and vegetables, alcohol and its impact on performance. Participants attended nutrition education sessions for six months, each one 20 to 30 minutes in duration. Interview and focus group discussions were administered to 20 Ethiopian national squad players and the head and two assistant coaches working with them. The data were analysed using manual coding matrices. The analysis of the interview data revealed that all the national team players exhibited significant knowledge of football nutrition after the nutrition education intervention. The intervention helped them to adhere to proper dietary and recovery procedures, and also significantly helped the players understand dietary CHOs as a vital source of fuel for football which as a result benefited them to change their misconception they had about CHO before the intervention. Some players had believed, at the beginning of the intervention, that alcohol had an ergogenic effect. In conclusion, this study revealed that nutrition education for professional football players can have positive results. The education programme must be entertaining and should not be too long. Based on these findings, was concluded that football players in Ethiopia would benefit from nutrition education targeting an improvement in nutrition knowledge and dietary practices. Key words: Ethiopian national squad football players, dietary practices, Nutrition education, nutrition knowledge. Study – 2. Similarly, to other professional football players, Ethiopian players require appropriate nutritional intake because of the physiological demands of the game. To understand the dietary practices and nutrition plans of these players, a dietary assessment of current Ethiopian professional players was conducted. The aim of this study was to assess the dietary intake of 126 players age M = 27.3, ±SD = 3.0 years), weight M = 72.4, ±SD = 7.0 kg, height M = 1.77, ±SD = .06 m, BMI M = 23.1, ±SD = 1.6 kg.m2 from seven Ethiopian premier league football clubs; during a competitive week, over a four-day period. Food was weighed and means (standard deviation) and 95% confidence limits were calculated and compared across clubs using one-way analysis of variance followed by Bonferroni post-hoc testing. There were significant differences in dietary macronutrient composition across the teams in the four study periods, the dietary intake in g/day and in g/kg of body weight for CHO on Thursday was significantly different M = 344.6, ± SD = 12.5, p = 0.030, g/day compared with Monday’s dietary CHO intake, in g/day and in g/kg of body weight, M = 308.3, ± SD = 96.4 g/day. The study revealed a dietary CHO intake was below the recommendation of 500-600 g/day. With great significant difference among clubs ranging from M = 459.9, ± SD = 104.1, p < 0.001. g/day to M = 256.0, ± SD = 58.5, p < 0.001 The mean dietary CHO, compositions in g/kg of body weight, across the teams were significantly different ranging from, 3.6 (.9) g/kg of body weight to 6.1 (1.3) g/kg of body weight.; In conclusion, the results show that the nutritional intake of the players was not optimal unlike protein and fat the mean daily CHO intake of Ethiopian professional football players was lower than recommended. These findings may have both short- and long-term negative consequences on the performance and recovery as well as health of the players. On the basis of our results, we recommended that nutritional education should be given to the players at an early age and should continue throughout adolescence. Key words: Ethiopian premier league, Dietary macronutrient intake, dietary assessment. Study – 3. It is important that football training load, which includes functional testing, is closely linked with optimal energy intake. This enhances performance and recovery process between training sessions. The aim of this study was to investigate the associations between dietary practice and performance and recovery of twenty professional Ethiopian football players from the same team (M = 23.8, ± SD = 3.3 years). During an intense seven-day, (Monday to Sunday) pre-season training period, food was weighed and recorded, and total and macronutrient energy intake was determined, and energy expenditure calculated. Performance testing (Yo-Yo Intermittent Recovery Test Level 1 (YYIR1) was also performed pre- and post the seven-day period. Data were expressed as the mean (standard deviation). A one-way ANOVA, with Bonferroni posthock testing, paired t-tests, Pearson correlation, and multiple regression were used in the statistical analysis. The mean dietary intake for protein was significantly higher in terms of daily intake in grams and per kilogram of body weight across the seven days ranging from M = 257, ± SD = 44, p < 0.001 g/day, to M = 168, ± SD = 24, p < 0.001, g/day. And M = 3.6, ± SD = .7, p < 0.001 g/kg of body weight to M = 2.3, ± SD = .4, p < 0.001 g/kg of body weight. Overall, our results show that the nutritional intake of the players was not optimal and resulted in a high mean daily energy deficit of M = -144.8, ± SD = 1111.7 calories was observed between the energy intake of M = 3765.1, ± SD = 1104.7 calories and the energy expenditure of M = 3909.9, ± SD = 191.2 calories. The study revealed that dietary fat was the highest source of energy, which is not the preferred fuel for football players. The mean distance covered post the seven days of training for the YYIR1 significantly decreased by 25% (pre: M = 2266 ± SD = 526 m versus post: M = 1666 ± SD = 456 m). This result represented a 10% decrease in VO2max values among the study participants from session 1 pre: M = 55.4 ± SD = 4.4 ml/kg/min versus post: M = 50.4 ± SD = 3.8 ml/kg/min. In summary, the YYIRT1 result may have been related to the energy deficit of the players over the seven days of pre-season training. In addition, players consumed higher levels of dietary fat and low levels of CHO during intense training, which is not the recommended for optimal performance and recovery in professional football players Key words: Preseason training, YYIRT1, energy balance and training load. In conclusion, the studies included in this thesis found that 1) elite Ethiopian football players benefitted from a sports nutrition education intervention, 2) there is a disparity in macronutrient composition across football teams participating in the Ethiopian Premier League and 3) energy deficit during a week of intense preseason training is associated with reduced performance and recovery of players.
The association between physical activity and body mass index, quality of life, life-space mobility and successful aging in older adults.
(2018) Naiker, Jacqueline.; Grace, Jeanne Martin.
The biggest threat to healthy aging is sedentary living with the golden years of most individuals being affected by disorders that are exacerbated by unhealthy lifestyles. Helping people age better is important and it can be achieved through participation in regular physical activity. Monitoring population levels of physical activity using subjective and objective measures is an important part of a public health response. This study aimed to determine the physical activity and body composition levels of older adults and the association of physical activity on body composition with health-related quality of life, life-space mobility and successful aging of life of older adults in Chatsworth, KwaZulu-Natal Province. A total of 210 older adults were randomly selected, both male and females, participated in the study and completed the Global Physical Activity Questionnaire, RAND Medical Outcomes Study 36-Item Health Survey, Life-Space Mobility Questionnaire and the Successful Aging Scale. BMI (kg/m2) was determined and step count was tracked for 7 days with the Omoron Pedometer. There were positive correlations between the participants actual physical activity and self-reported physical activity levels (r=0.183, p=0.008). The majority of the participants were overweight (51%, n=107). There was no significant relationship between BMI (r=0.63, p=0.366) and actual steps taken as well as no significant correlation with SF-36 and the average number of steps in 7 days of the participants (r=-0.112, p=0.107). A significant correlation between total LSQ (r=0.224, p=0.001) and SAS (r=-0.152, p=0.027) with the average number of steps in 7 days of the participant was noted. It was concluded that there is a positive relationship between self-reported physical activity and actual activity and life-space mobility and successful aging of life in older adults, but such relationship is not meaningfully predictive in this population. Strategies to improve physical inactivity in the elderly need to be implemented to ensure successful aging and quality of life in the elderly.
Anthropometric profile and physical performance of youth players and challenges in the Ethiopian football talent identification program.
(2018) Gebreegziabher, Eyasu Merhatsidk.; Van Heerden, Jaques Johan.
The purpose of this study was to investigate the existing challenges that hinder the implementation of the talent identification program. Understand and develop basic standards to recruit talented young players based on their anthropometric and physical quality also the purpose of this study. Other purpose of the study was formulated and implement effective strategies for the coaching program. The study employed a cross-sectional study design. A homogenous group of 240 male Ethiopian football players (Age 15.6 ± 1.8 years) from 12 teams participated in this study. Sixty-one football coaches and 61 sport administrators also participated. Anthropometric assessment, speed, power, agility, endurance and flexibility tests were conducted. The data was analysed using descriptive and inferential analysis techniques. The mean and the standard deviation of results across an anthropometric profile for all players are as follows: body mass weight was 55.47kg (6.14), standing height was 1.7m (0.06), body mass index was 19.12kg/m2 (1.99), sub-scapular skinfold was 6.88mm (1.37), triceps skinfold was 5.95mm (1.51), BF(Body Fat) % was 15.53% (2.91) and LBM(Lean Body Mass) was 46.82kg (5.11). Significant weight and height differences (p≤0.05) were found between club and academy players, but not in BMI, % BF and Lean Body Mass (LBM). club players had significantly greater body mass than EFF and academy players (p≤0.05). For standing height, club and EFF players were significantly taller than players in the academy teams (p≤0.05). The mean and the standard deviation of overall fitness values for all players were as follows: 10m speed was 2.15sec (0.19), 20m speed was 3.51sec (0.29), 40m speed was 5.16sec (0.31), sit and reach flexibility was 12.94cm (7.86), vertical jump power test was 42.93cm (6.58), Illinois agility test was 17.45cm (0.83) and V̇O2 max 49.74ml/kg/min (5.42). Mean values per setting from club, academy and EFF, respectively were: 10m speed 2.08sec, 2.26s and 2.14sec (p≤0.0001); 20m speed 3.4sec, 3.7sec and 3.49sec (p≤0.0001); 40m speed 5.87sec, 5.9sec, 6.07sec (p≤0.0001). Flexibility was 11.96cm, 11.31cm and 14.96cm (p≤0.05). Club’s youth players were taller, heavier, faster and more flexible than academy and Ethiopian football federation players. Significant differences were found in age groups: 10m speed between U-14 and U-15 (p≤0.01) and U-14 and U-17 (p≤0.05), In 20m speed between U-14 group and U-16 (p≤0.01) and U-14 and U-17 (p≤0.01). Significant iv differences were also found in 40m speed between U-14 and U-15 (p≤0.05). Older age players were faster than younger ones. Anthropometrical profiles and physical performance tests may assist to identify the talented players in the country. Significant differences found per climatic altitudes and geographical locations were as follows: high altitude players’ significantly greater body mass than low altitude players (p≤0.05). Low altitude players significantly better BMI than high altitude players (p≤0.0001). For LBM, high altitude players significantly greater results than low and moderate altitude players (p≤0.005). The moderate altitude group of players performed better results than the low and high-altitudes group of players. Eastern and northern players were significantly heavier than southern and western players. Compared to southern players, Eastern and northern players were significantly taller than southern and western players. Although players from eastern, performed better in the 10m speed test than western players. Regarding the 20m speed test, eastern players performed better results than the rest three altitudes groups. A correlation matrix comparing anthropometry and physical performance indicated that: BMI was negatively related with 10m sprint (r = 0.134), 40m sprint (r = 0.232), vertical jump (r = 0.108) and agility (r = 0.123). Height was negatively related to performance in the 20m sprint (r = 0.141), 40m sprint (r = 0.201) and agility (r = 0.255). Quantitative questionnaire data related to the practice of talent identification programs in Ethiopia showed that: Most of the players (62%) have information and knowledge about a talent identification program. Most players (74%) have also experienced or passed through a talent identification program. The same was true of most players (74%) being of the opinion that they were exposed to a proper training program. Player’s knowledge and experiences; with respect to rest, water, materials and playing fields; family and coach support and test batteries found statistically significant differences (p≤0.0001) between club, academy and Ethiopian football federation settings. For the questionnaires about knowledge and experiences of coaches in the talent identification program, no statistically significant differences were found among club, academy or Ethiopian football federation settings, whereas significant differences were found with respect to experiences on upgrading of coaching knowledge related to talent v identification, in academy and Ethiopian football federation (p≤0.05) TIP (Talent Identification Program) settings. For the questionnaires related to problems and solutions of talent identification program, statistically significant differences in opinion were found among club, academy and Ethiopian football federation settings, but opinions about incorporation of talent identification programs in training courses were not significantly different. In terms of setting up programs to evaluate the level of performances of the players, not all settings were in the affirmative. For the implementation or application of talent identification programs, statistically significant differences in opinion were found across club, academy and Ethiopian football federation (p≤0.0001) settings. However, no differences were found fin terms of using a manual to identify player’s talent. For the questions about availability of materials and equipment for the TIP (Talent Identification Program) statistically significant differences in opinion were found among coaches in clubs and the Ethiopian football federation, while only those in the Ethiopian football federation TIP felt that testing materials are appropriate. For all questionnaires about administrators’ knowledge and experiences of talent identification, statistically significant differences were found in all groups. Questions on knowledge about TIP and facilitating refreshment courses for the coaches on talent identification were not statistically difference. For the questions about problems and solutions for the talent identification program, opinions varied statistically whereas opinions regarding their team’s conducting talent identification program and motivation of the players were similar. For the questionnaires about implementation responsibility of talent identification programs, statistically significant differences were found among the club, academy and Ethiopian football federation settings. For the questionnaires about manpower and materials for the talent identification program, statistically significant opinions were found among all the club, academy and Ethiopian football federation TID settings. For open-ended questions, all responses were investigated by using the detective qualitative data computer software package (NVIVO). The themes identified focussed on problems, solutions and suggestions for the operation of the Ethiopian football talent identification program. Under the three themes, focus nodes were identified as being the vi system, knowledge and experience, hard-work, training, monitoring and support, manpower, while facilities and equipment were also mentioned. The football talent identification program in Ethiopia is not an optimally functioning system. The improvement of the system is the first essential element for the talent identification program. This research has shown the need for a new systematic structure to be established for the talent identification program. Scarcity of knowledge and experience, also affects the talent identification program. Education and training were offered as keys to a solution.
Long distance running in Ethiopian athletes: a search for optimal altitude training.
(2018) Tola, Zeru Bekele.; McKune, Andrew James.
ABSTRACT Background The extended dominance of Ethiopian and Kenyan middle- and long- distance athletes in world athletics has resulted in researchers proposing numerous explanations to explain this success. Genetic predisposition, anthropometric, physiological, biochemical and biomechanical characteristics, environmental factors like living and training at high altitude, active lifestyles during childhood as well as nutritional practices, have all been major focus areas of past studies that involved east African endurance athletes. Of all the proposed variables, researchers have acknowledged the positive role of environmental factors in the success of these athletes. Despite the past attempts to investigate the major factors that contributed to the successes of east African athletes, to the best of the authors’ knowledge, limited studies have addressed each of the proposed physiological and environmental variables in the Ethiopian athletes, compared with the number of studies conducted on Kenyan athletes. Purpose The primary purpose of this research was to test a natural altitude training model and examine whether it enhanced the long-distance performance of junior Ethiopian athletes. The research also examined a variety of environmental factors associated with these junior athletes that included daily distance travelled to and from school, mode of transport to and from school as well as physical activity patterns after school. These factors were compared between the junior athletes who participated in the altitude training study, current and retired World and Olympic level long-distance Ethiopian athletes. The energy intake, macronutrient breakdown and energy expenditure of the junior athletes during the altitude training camp were also analysed. Methods Demographic Characteristics Study: A total of 83 endurance runners were involved in this study. The athletes were classified into three separate groups based on their current performance status and age as retired elite (n = 32), current elite (n = 31) and academy junior athletes (n = 20). The average ages of the athletes in the three groups were 38±7.6, 25±4.5, and 18±1.2 years for retired elite, current elite and junior group athletes, respectively. The study primarily employed a xvi questionnaire survey design to gather the demographic characteristics of the athletes. Along with the questionnaire, the altitudes where the athletes were born and trained, as well as the home to school distance of the athletes were measured. Data were collected from the retired athletes through both self- and interviewer-administered questionnaires and forms. Self-administered questionnaires were used to collect data from the current elite and academy junior athletes. Only 46.8% of the retired elites (n=15) filled in the questionnaire and the rest 53.2% (n=17) of the retired elite athletes responded to the questionnaire via telephone. The home to school distance of 71.8% (n = 23) and 58.1% (n = 18) of retired and current elite athletes, respectively, was measured physically using a watch with Global Positioning System (Garmin forerunner, 910X). Macronutrient Intake and Energy Balance Study: In this study, twenty (male = 16 and female = 4) junior long-distance athletes participated. The athletes were attending an eight-week training in the camp where they were living in and training in and around Tirunesh Dibaba National Athletics Training Centre (TDNATC) located at an altitude of 2500m (7°57′N latitude and 39°7′E longitude). The study used the three-day direct dietary record method. Nude body weight measurements were taken before and after the three assessment days. All food measurements were carried out when the three meals were served: breakfast (8:00 – 9:00am), lunch (12:00 am – 1:00pm), and dinner (6:00 – 7:00pm). All the measurements were taken and recorded by the principal investigator, together with the head coach of the athletes, using a digital weighing scale readable to 1 gram (Salter Housewares LTD, England) and the dietary analysis of each individual athlete, including the total energy intake, and the energy contribution and gram values for carbohydrate, fat and protein from the consumed foods was performed using the nutritional software package Nutritics (v3.7, University Edition). Training type, intensity and duration, as well as external load, including distance, time covered and speed of the training were recorded in a daily training diary over the three consecutive days. Total energy expenditure of each study participant was calculated from basal metabolic rate (BMR) using the Schofield equation (1985) and the physical activity ratio (PAR), and physical activity level (PAL). xvii Altitude Training Study: A total of 20 (male = 16 and female = 4) junior long distance athletes lived and trained in and around the Athletes Tirunesh Dibaba National Athletics Training Centre were recruited for the study. The study applied the balanced, randomised, experimental design. Before the athletes were randomly assigned to the live high - train high (LH-TH) control (n = 10 ) and live high - train high train low (LH-THTL) experimental (n = 10 ) groups, they were tested on a 5km track race at baseline (end of four pre-experimental weeks) and then assigned equally into the two groups based on their 5km performance (time) and gender. The study lasted for a continuous eight weeks where all the athletes lived in every day of the week, and trained light and moderate intensity sessions at an altitude of 2500m a.s.l. four times per week. In addition, the LH-TH and LH-THTL groups trained separately at 2500m and 1470m a.s.l. in high intensity sessions two days per week, respectively. During the study time, different haematological, autonomic, neuromuscular, subjective training monitor and five kilometre performance time trial tests were conducted. Resting haematological tests were conducted three times (baseline, week four and week eight). Sample blood was drawn from a cubital vein under standard conditions (off-training days, between 08:30 and 09:30 a.m. before breakfast and after a 10 minute rest period in a sitting position) in the haematology laboratory of the College of Health Sciences of Arsi University, Ethiopia at the specified time for complete blood count ( CBC) analysis. Like the haematological tests, three consecutive vagal related heart rate measurements (heart rate variability and one- and two-minute heart rate recovery measurements) were taken at baseline, week 4 and week 8. The heart rate variability measurements were taken early in the morning, before the athletes left for training, in their bedrooms (before leaving their beds). The one- and two-minute heart rate recovery tests were taken as soon as the three 5km time trials were completed at baseline, week 4 and week 8. Along with the CBC and vagal-related heart rate measurements, five consecutive neuromuscular fitness tests (at baseline, week 2, week 4, week 6 and week 8) using the common vertical jump tests (counter movement (CMJ) and squat jump (SJ) test) were conducted after 10 hours of light intensity training. For a total of 47 training sessions, subjective training load responses were collected using a session rating of perceived exertion (session-RPE) methods within 30 minutes after the end of the day’s workout. At baseline, week four and week eight xviii three 5km endurance performance tests were conducted on a 400m standardized synthetic track under standard conditions (at 2500m a.s.l. and between 07:00 – 08:00 a.m.). Results Demographic Characteristics Study: Although the demographic characteristics study identified significant difference between the three groups in the age at which formal training started (p < 0.001), no significant difference was identified between the groups (p > 0.05) regarding the altitudes where the athletes were born and raised. Moreover, the study reported no significant difference in the daily distance covered to and from school between the three groups during their primary education (p > 0.05) but not during their secondary education (p < 0.05). The study also revealed that there were significant regional distribution differences in the three groups (p = 0.002) where 81.3% of retired athletes and 55% of academy junior athletes were from central Ethiopia. There was also no significant difference (p = 0.05) between the three groups in the mode of transportation used to cover the daily distance to and from school. In addition to the above findings, this study also found no statistically significant difference in the types of major out-of-school activities between the three groups of athletes during their childhoods (p > 0.05). Macronutrient Intake and Energy Balance Study: There was a significant difference between the mean total energy intake (14593±895KJ.day-1 ) and mean total energy expenditure (13423± 1134 KJ.day-1 , p < 0.001) during the three days’ dietary assessment. Moreover, the daily total energy intake (EI) and energy expenditure (EE) throughout the three days for all subjects were also compared in the same way as the total EI and EE. In comparison to the daily energy expenditure, on day one there was a mismatch between EI (15682 ± 1599 KJ.day-1 ) and EE (12823 ± 1397KJ.day-1 , p = 0.000), and a positive energy balance was calculated. On day two there was no substantial difference between daily EI (14368 ± 1516KJ.day-1 ) and EE (13688± 1618 KJ.day-1 , p = 0.146). Similarly, there was also no significant difference between the EI (13728±412KJ.day-1 ) and EE (13757± 1390KJ.day-1 , p = 0.919) on day three. This study also confirmed no significant differences in the daily energy expenditure between the three days (p = 0.091). As compared to fat and protein, it appears that CHOs were the major energy source consumed during the three days. The overall proportion of the energy derived from the foods revealed that CHO provided 65.7% (±11.7 %); protein 18.7% (±6.9 %) and fat 15.4% (±4.9 %). xix When the overall proportions of energy intake (KJ) derived from the three macronutrients were analysed on a daily basis, there were statistically significant differences in CHO, protein and fat consumption across the three days, (p < 0.001). Moreover, substantial differences were identified in the day-to-day fat (p < 0.001) and protein (p < 0.001) consumption during the three dietary assessment days. Altitude Training Study Haematological Study: No statistically significant difference in RBC count was observed between the LH - TH and LH - THTL study groups following eight weeks of endurance training (∆0.05; CL ±0.029; p = 0.741; ES = 0.12). After eight weeks of endurance training no significant difference was observed in the haemoglobin concentration (p = 0.926), but substantially declined from baseline to week eight in both groups (Experimental: ∆-0.48; CL±0.46; p = 0.040; ES = - 0.35 and control: ∆-0.51; CL± 0.46; p = 0.030; ES = -0.37). This study also identified no substantial difference in haematocrit value between the two study groups following eight weeks of endurance training (∆0.2; CL±1.9; p = 0.832; ES = 0.06). Vagal-Related Heart Rate Response: The resting HRV (RMSSD) measurements revealed no meaningful differences between the LH-TH and LH - THTL groups (∆-0.18; CL±0.43; p = 0.407; ES = -0.29) from baseline to week eight in the experimental (∆0.05; CL±0.31; p = 0.761; ES = 0.08) and control (∆0.22; CL±0.31; p = 0.145; ES = 0.37) groups; although the changes in both groups were positive. The difference between the experimental and control groups, however, was negative and small (∆-0.29). The regression analysis also revealed no significant differences, both in the one-minute (∆4.4; CL±10.8; p = 0.413; ES = 0.47) and two-minute postexercise heart rate recovery (∆3.1; CL±10.4; p = 0.550; ES = 0.31), between the experimental and control groups. Neuromuscular Fitness/Fatigue Response: The CMJ test results revealed no significant difference between the two study groups following eight weeks of endurance training (∆0.5; CL±4.8; p = 0.829; ES = 0.06), although meaningful changes were identified both in the experimental (∆8.3; CL ±3.4; p = 0.001; ES = 0.92) and control (∆7.8; CL ±3.4; p = 0.001; ES = 0.86) groups from baseline to week eight. Significant changes in squat jump ability were xx observed, both in the experimental (∆4.8; CL±2.8; p = 0.001; ES = 0.69) and control (∆2.9; CL±2.8; p = 0.039; ES = 0.42) groups, following eight weeks of endurance training; but not between the groups (∆1.8; CL±3.9; p = 0.353; ES = 0.26). This study also confirmed no significant difference between the two study groups in the eccentric utilisation ratio following eight weeks of endurance training (∆-0.05; CL±0.16; p = 0.511; ES = -0.39). Training Load Response: The results of the analysis identified significant differences between the groups, and for all weekly training load responses of all training sessions, i.e., light, moderate and high-intensity training sessions (p = 0.019) and high intensity training sessions (p = 0.000). However, no substantial difference was identified between groups (p = 0.133) in the weekly load responses to the light and moderate intensity training sessions. Based on the results of the least significant difference, post-hoc meaningful differences were identified between the groups in their weekly load response to the total intensity training at week seven and eight; as well as at weeks one, five, seven and eight for the high intensity training sessions. Out of the 47 training sessions, light intensity sessions (< 4 RPE, less than the first ventilatory threshold) made up 87.2% of sessions in the experimental group and 68.1% in the control group, while 12.8% (Experimental group) and 31.9% (Control group) of the training sessions were completed at RPE > 4 < 7 RPE (between first and second ventilatory threshold). Five Kilometre Endurance Performance: After eight weeks of endurance training no significant difference in the 5km endurance performance was identified between the LH-TH and LH-THTL study groups (∆-12; CL ±25s; p = 0.335). Even though times for the 5km decreased significantly in the experimental group (∆-19; CL±18s; p = 0.037) from baseline to week eight, performance in the control group did not improve significantly (∆-7; CL ±18s; p = 0.440). Conclusions Demographic Characteristic Study: Significant difference was observed between the three groups in the age at which formal training started. However, no significant differences were identified between the three groups in the altitudes where the Ethiopian long-distance athletes were born and raised, the daily distance travelled to and from school, the mode of transportation and the major out-of-school activities during their childhood. Thus, the findings of this study xxi confirmed that the 20 junior athletes who were involved in the study shared common demographic characteristics with the retired and current elite Ethiopian long-distance athletes. Macronutrient Intake and Energy Balance Study: In line with the previous studies conducted on Kenyan and Ethiopian endurance athletes, the young long-distance Ethiopian athletes met the recommended daily macronutrient intake for carbohydrates and protein for endurance athletes. However, the study also identified that the athletes’ dietary fat consumption was below the recommended amount for endurance athletes. Moreover, based on the three-day dietary assessment results, the young Ethiopian endurance athletes were found to be in a state of positive energy balance one week before their first major competition of the year (albeit during the preparation phase of their yearly training plan). Altitude Study: The overall results of the current altitude study revealed that in most of the study variables (i.e., haematological, autonomic, neuromuscular, and endurance performance), except the subjective based training load response, statistically insignificant results were identified between the two study groups. However, when the results of the altitude study variables across time (baseline to week eight) were examined, athletes in the LH-THTL experimental group showed better progress in neuromuscular and lower training load responses which were accompanied with significant five kilometer endurance performance change; and lower or similar progress in haematological and autonomic regulation responses as compared with the LH-TH control group. It is noted that the ultimate purpose of any type of altitude training is enhancing the running performance while minimizing athlete’s susceptibility to injury. Taking these core concepts of athletic training and the physiological and performance changes of the current study in to consideration, the LH-THTL altitude training model was potentially the preferred optimal altitude training model to further enhance the past and existing long-distance performance of Ethiopian endurance athletes although further comprehensive studies are required to confirm the results. Future Directions In order to exhaustively investigate optimal altitude training models that better enhance the longdistance performance of athletes’ native to high altitude, more comprehensive, similar studies xxii should be designed. Moreover, to achieve stronger results, further studies should be conducted using larger sample sizes with balanced gender proportions, along with more subjective and objective training monitoring methods. Furthermore, future studies should consider additional altitude training models, be conducted over longer periods and during different phases of the yearly training plan (preparation, pre-competition, and competition). It is also recommended that future studies should design endurance performance tests at different altitudes (low and high) to enhance the local and international competition performance of Ethiopian long-distance athletes.
Effects of high or moderate intensity training on inflammation and endothelial function in insulin resistance.
(2019) Thaane, Tshidi.; McKune, Andrew James.; Motala, Ayesha Ahmed.
Exercise training improves insulin resistance (IR) via numerous mechanisms including improved endothelial function and reduced systemic inflammation. However, it is unclear whether high intensity interval training (HIIT) offers superior benefit when compared with continuous moderate intensity training (CMIT) in a clinical population. This thesis reports findings from a clinical trial designed to determine the effects of short-term high or moderate intensity training on inflammation and endothelial function in overweight/obese adults with IR. Furthermore, the thesis provides a report on factors associated with IR in this population. Clinical examinations (body composition), blood tests [serum insulin and serum C-reactive protein (CRP), plasma glucose] and physiological tests (microvascular function and aerobic fitness tests) were undertaken on consenting individuals who volunteered to participate in the study. Study participants were stratified into IR and insulin sensitive (IS) groups based on their homeostatic model assessment (HOMA-IR) scores. The IR and IS groups were each further randomized into control (CNT), HIIT or CMIT sub-groups. The HIIT and CMIT sub-groups underwent baseline measures and exercise training for 10 consecutive days, followed by a repeat of baseline measures. The CNT sub-group was tested at baseline and post follow-up without taking part in the exercise intervention. When compared with CMIT, HIIT produced a greater improvement in markers of IR [(HOMA-IR); 32% vs. 9% by CMIT] and endothelial function [(PORHmax and MV); 37.59% and 27.45%, respectively, vs. 8.24% and -25.71%, respectively, by CMIT]. These improvements occurred without changes in body fat or aerobic fitness. Cohen’s (d) effect sizes indicated that the improvements produced by HIIT were large, while those of CMIT were unclear, suggesting that HIIT may be the ideal mode of training when the primary goal is to improve IR and endothelial function in overweight/obese adults. Cross-sectional analysis of baseline data indicated that the acute-phase inflammatory protein, CRP, was strongly associated with IR in black Africans. However, this association was only significant in males. Suggesting that CRP has potential clinical application as a maker of systemic inflammation in this population. The gender of the patient, however, must be taken into consideration.
The development of a professional development programme for physical activity promotion in adolescents' physical education classes, Nigeria.
(2020) Osifeko, Olalekan Remigious.; Naidoo, Rowena.; Chetty, Verusia.
Introduction: Nigerian adolescents are physically inactive and unable to enjoy the health benefits of exercise, due to the lack of physical activity (PA) during physical education (PE) classes. Adolescents’ PA can be promoted in different environments, such as at school and in the wider community. Schools promote PA through school sports, at lunch break and in PE class. School-based interventions in PE classes have been effective in promoting PA in adolescents and encouraging healthy lifestyles. Purpose of the study: To develop a professional development programme for PE teachers in junior secondary schools and to evaluate its impact on students in order to improve PA in Nigerian schoolgoing adolescents. Methods: This study employed a mixed-methods approach, including intact group and action research designs. A purposive sample of 1200 students were recruited from twenty-four junior secondary schools, from the Epe local government area, in Lagos State East senatorial district, Nigeria. The schools were sampled and purposively assigned to an intervention group (n= 14) and a control group (n= 10). Teachers (n=14 intervention; n=10 control) and students (n=695 intervention; n=498 control) participated in the study. Students completed the Attitudes and Practices of PA for Adolescents (QAPPAA) questionnaire pre- and post-intervention. A PE teacher from each school participated in the teacher-training intervention (n=24) and in focus group discussions pre- and post-intervention. The professional development training (PDT) was designed, based on the focus group discussions (FGDs) and information from the related literature. The data collection tools for pre- and postintervention were teacher FGDs and validated student questionnaires. Quantitative data were analysed with the use of a statistical package (IBM SPSS Statistics version 25, US) which performed descriptive and inferential tests and analysed significant differences between pre- and post- intervention. The one-sample t-test was applied to test for significant agreement or disagreement to statements measuring attitude to PE, pre- and post-scores. Analysis of covariance (ANCOVA) was used to test the post-intervention scores, to determine the interaction effects of categorical interval scale variables. The Wilcoxon Signed Ranks test was applied to observed differences between the two dependent measurements, to discover whether there was a statistically significant difference in mean scores or not. Lastly, the analysis of the qualitative FGDs was carried out with the aid of computer-assisted data analysis software (Nvivo 12), to identify and interpret themes and sub-themes that emerged from the FGDs.

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