Thesis (MNutr)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Background: Very little data exists regarding the nutritional status of adolescent soccer players and there is no national data regarding this population. Aim: The aim of this study was to investigate the dietary intake and anthropometric profile of N=39 male, high-performance, adolescent soccer players who are of mixed race (14 -18 years of age), during the competitive season. Methods: The study design was a descriptive, observational study with an analytical component. A quantified food frequency questionnaire (QFFQ), which has been validated for athletes, was used to characterise their nutritional intake in terms of energy (kCal), macronutrient as well as micronutrient intake. Interpretation of anthropometric data included plotting and interpreting growth indicators such as height-for-age, body mass index (BMI)-for-age, tricep skinfold-for-age, subscapular skinfold-for-age, sum of skinfolds-for-age, arm muscle area (AMA)–for-age, arm muscle circumference (AMC)-for-age, arm fat area (AFA)-for-age and percentage body fat. Results: The anthropometric data showed that most of the players had an adequate height-for-age (100%, N=39) and BMI-for-age (87.2%, N=34). The mean percentage body fat was 10.9±3.5%. The majority of players’ skinfold thickness measurements were above the 85th percentile for triceps (56.4%, N=22), subscapular (59.0%, N=23) as well as the sum of two skinfolds (triceps and subscapular), (72.0%, N=28), AMA (82.1%, N=32), AMC (56.4%, N=22) and AFA (56.4%, N=22). Daily minimum and maximum mean energy expenditure was between 3146.9±213.4 and 3686.4±250.0 kcal while daily mean energy intake was 4374.0±1462.4 kcal. Protein (156±53 g/day), carbohydrate (CHO) (557±172 g/day), total fat (149±67.8 g/day) and cholesterol (546±230 mg/day) intake were all above levels recommended for athletes. The mean micronutrient intake met the estimated average requirement (EAR) or adequate intake (AI) for all nutrients. Players who were more physically active displayed more favourable anthropometric indices which included body weight, BMI, body fat indices as well as muscle mass indices, despite having a greater total energy intake (TEI). This difference did however not reach statistical significance. Supper was the most regularly consumed meal (97.4%, N=38). The majority of players (61.5%, N=24) ate breakfast daily with only 5.1% (N=2) who never ate breakfast. However, 20.5% (N=8) of the players only ate breakfast 3 days a week. Conclusion: Although most of the players had a normal body weight and BMI, they were predominantly categorised as above average according to indices of body fat. Body muscle indices was categorised as above average for most players suggesting a beneficial finding in terms of sporting performance. The mean TEI, CHO, protein intake and fat intake were all above the recommended levels for athletes. The mean intake of all vitamins and minerals met the EAR/AI. Players who were more physically active displayed more favourable anthropometric indices, despite having a higher TEI. Although this study population exhibited no evidence of stunting, indicating that the players were well nourished (in terms of sufficient macronutrients and micronutrients), they are at risk of being over-nourished which may negatively impact sporting performance as well as overall health. / AFRIKAANSE OPSOMMING: Agtergrond: Daar is baie min studies wat die dieetinname van adolosent-sokkerspelers ondersoek het en daar is sover die navorser se kennis strek, geen nasionale data rakende dieetinname in hierdie studie populasie nie. Doel: Die doel van die studie was om die dieetinname en antropometriese profiel van N=39 manlike hoë-prestasie adolosent-sokkerspelers van gemengde ras (14-18 jaar) gedurende die kompeterende seisoen te bepaal. Metodes: ‘n Kwantitatiewe voedselfrekwensie vraelys was gebruik om die totale energie (kcal), makronutriënt- en mikronutrientinname te bepaal. Die antropometriese data was geïnterpreteer met behulp van die volgende groei indikatore; lengte-vir-ouderdom, liggaamsmassa indeks (LMI)-vir-ouderdom, trisep velvou-vir-ouderdom, subskapulêre velvou-vir-ouderdom, som van velvoue-vir-ouderdom, arm spier area (ASA)-vir-ouderdom, arm spier omtrek (ASO)-vir-ouderdom, arm vet area (AVA)-vir-ouderdom en persentasie liggaamsvet. Resultate: Die antropometriese data het getoon dat meeste van die spelers toepaslike lengte-vir ouderdom (100%, N=39) en LMI-vir-ouderdom (87.2%, N=34) het. Die gemiddelde persentasie liggaamsvet was 10.9±3.5%. Die meerderheid van die spelers se velvou metings was bo die 85ste persentiel vir die trisep (56.4%, N=22), subskapulêr (59.0%, N=23) sowel as die som van twee velvoue (trisep en subscapulêr), (72.0%, N=28), ASA (82.1%, N=32), ASO (56.4%, N=22) en AVA (56.4%, N=22). Die daaglikse maksimum en minimum gemiddelde energie verbruik was 3146.9±213.4 tot 3686.4±250.0 kcal en daaglikse energie inname was 4757.9±2121.2 kcal. Proteïen (155.6±53.3 g/day), koolhidraat (556.8±172.1 g/day), totale vet (148.8±67.8 g/day) en cholesterol (545.5±230.1 mg/day) inname was bo die aanbevelings. Die gemiddelde mikronutriënt inname was binne die geskatte gemiddelde aanbeveling of toereikende inname vir al die mikronutriënte. Die gemiddelde vloeistof inname gedurende ‘n sokker wedstryd en ‘n twee uur oefen sessie was 479.1±163 ml en 597.7±281 ml, onderskeidelik. Die meer aktief spelers het ‘n meer geskikte antropometriese profiel, soos laer gewig, LMI en liggaamsvet waardes en hoër spiermassa waardes beskik, ten spite van ‘n hoër energie inname. Die maal wat die mees gereeld geëet was is aandeete (97.4%, N=38). Meeste (61.5%, N=24) van die spelers het ontbyt daagliks geëet met net 5.1% (N=2) wat nooit ontbyt geëet. Alhoevel daar nogsteeds 20.5% (N=8) van spelers was wat net ontbyt 3 keer per week geëet het. Die maaltyd wat die minste ingeneem was, was ontbyt, met net 20.5% (N=8) wat onybyt 3 dae per week eet. Slot: Alhoewel meeste van die spelers ‘n normale gewig en LMI getoon het, is die meeste spelers gekatogoriseerd as bo gemiddeld in terme van liggaamlike vet waarde. Die meeste van die spelers kan ook gekatogoriseer word as bo gemiddeld in term van spiermassa, wat voordelig is vir sport prestasie. Die gemiddlede energie, koolhidraat, proteïen, en vet innames was bo die aanbevole reikwydtes. Die gemiddelde mikronutriënt inname was binne die geskatte gemiddelde aanbeveling of toereikende inname vir al die mikronutriënte. Meer aktief spelers het ‘n meer geskikte antropometriese profiel getoon, ten spite van ‘n hoër energie inname. Alhoewel hierdie populasie wel gevoed is, in terme van makronutriënt en micronutrient, draar hulle ‘n risiko om oor gevoed to wees. Dit mag hulle sport prestasie en algehele gesondheid negatief beïnvloed.

Adolescent athletes of this era are more pressurized than adolescents of previous generations to perform at an optimum level (Micheli & Jenkins 2001, p49). The importance of winning can result in adolescent athletes developing inappropriate nutritional practices such as neglecting hydration and consuming insufficient carbohydrate (Micheli & Jenkins 2001, p57). Consuming insufficient fluid leads to dehydration which reduces a soccer player’s ability to continue training. Consuming inadequate carbohydrate reduces performance and blood glucose levels during training. This study aimed to determine the hydration status, fluid and carbohydrate intake of male, adolescent soccer players during training. A cross-sectional study was conducted among 122 amateur male, adolescent soccer players (mean age = 15.8 ± 0.8 years; mean BMI = 20.4 ± 2.0 kg/m2). The players’ hydration status before and after training, was measured using urine specific gravity and percent loss of body weight. Their carbohydrate intake, as well as the type and amount of fluid consumed, were assessed before, during and after training. A questionnaire was administered to determine the players’ knowledge regarding the importance of fluid and carbohydrate for soccer training. The study had an 87.1% response rate. The mean environmental conditions did not predispose players to heat illness. However, the players were at risk of developing heat illness during six of the 14 training sessions. Although the mean urine specific gravity indicated that players were slightly dehydrated before and after training, 43.8% of players were very or extremely dehydrated before training and 53.6% after training. A few (3.3%) were extremely hyperhydrated before training and after training (7.0%). On average players lost less than 1% of body weight during training and less than 3% of players dehydrated more than 2%. Players consumed mainly water before (289.17 ± 206.37 ml), during (183.20 ± 158.35 ml) and after (259.09 ± 192.29 ml) training. More than 90% stated that water was the most important fluid to consume before, during and after training. Very few (4.7%) correctly stated that carbohydrate should be consumed before, during and after training. Players were found to be slightly dehydrated before and after training and therefore were not consuming enough fluids during training. Players consumed inadequate amounts and types of fluid and carbohydrate. This not only compromises their performance but also health. Players were not aware of the importance of fluid and carbohydrate for soccer training. This study is unique in that it focused on the carbohydrate and hydration practices of socioeconomically disadvantaged adolescent soccer players during training. The study sample therefore represents a high risk group about which there is limited published data both locally and internationally. This study generated important baseline information which was lacking before on the hydration status, fluid and carbohydrate intake of adolescent soccer players in South Africa. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.