The purpose of this thesis was to determine ways to maximize creatine uptake and retention during creatine supplementation. Since there are many factors that affect muscle creatine concentrations, a series of studies were performed. In the first study, the purpose was to determine if á-lipoic acid aided creatine uptake and retention. It was hypothesized that á-lipoic acid would increase creatine uptake, because it has been found to increase glucose disposal in animal studies and because creatine uptake has been found to be related to increased glucose transport. Results showed that phosphocreatine and total creatine increased following supplement intervention. In the second study, the purpose was to develop an optimal dose of creatine in order to minimize urinary excretion of creatine. It was hypothesized that individuals with more lean tissue mass would excrete less urinary creatine during consumption of the same loading dose. There was a high negative correlation between lean tissue mass and urine creatine excretion. Regression equations were developed for the relationship between lean tissue mass and urine total creatine and used to determine the amount of creatine to ingest relative to lean tissue mass that would result in minimal creatine losses in urine. Based on these results, a creatine dose of 0.22 [right arrow] 0.25 g/kg lean tissue mass/d was recommended. In the third study, the purpose was to determine if a habitual vegetarian diet resulted in lower muscle creatine and phosphocreatine concentrations compared to an omnivorous diet. A secondary purpose was to determine if creatine supplementation and weight training resulted in greater increases in muscle metabolite content, muscle fiber area, lean tissue mass, and strength in vegetarians compared to non-vegetarians. Results indicated that vegetarians had lower resting total creatine concentration, and that creatine supplementation and weight training led to greater increases in muscle phosphocreatine and total creatine in vegetarians compared to non-vegetarians (p < 0.0125). The supplement and exercise intervention eliminated the differences in intramuscular total creatine concentration that existed prior to the study. Type II muscle fiber area, lean tissue mass, total work output, and 1-RM bench press increased to a greater extent following creatine supplementation compared to placebo supplementation (p < 0.017), with no difference between vegetarians and non-vegetarians. (Abstract shortened by UMI.)

The purpose of this investigation was to determine the effects of a four day creatine load and simultaneous energy restriction on muscle creatine content, exercise performance, and body composition in 24 male recreational resistance trainers, age 18-26. Sixteen subjects were randomly divided into placebo (Pl, n=8) and creatine supplement (CrS, n=8) groups. Control (C, n=8) subjects of the same age were recruited separately g à d-1 to complete the performance and body composition tests while consuming their normal diet. The CrS group was administered 20 g à d-1 of creatine monohydrate (Cr) mixed with 5 g à d-1 of sucrose, while the Pl group was administered 25 of sucrose. Both CrS and Pl consumed a formula diet of 75.3 kJ (18 kcal) à kg-1 à d-1 for 4 d. Testing before and after energy restriction consisted of a repeated sprint cycle performance test (10 sprints of 6s, with 30s rest), hydrostatic weighing, and resting needle muscle biopsy. Testing revealed that subjects in CrS and Pl demonstrated significant decreases in body weight and % body fat (%BF) with no difference between groups. However, Pl demonstrated a significantly greater % loss in FFM (2.4 ± 0.25%) compared to CrS (1.4 ± 0.4%) (p<0.05). The muscle fuel stores of CrS and Pl responded significantly to the diet. Significant increases in muscle total Cr (p<0.01), free Cr (p<0.01), and CrP (p<0.05) of 16.5%, 16.8%, and 16% respectively were demonstrated by CrS over the energy restriction period, while Pl demonstrated significant decreases of 7.2% and 8.2% respectively in muscle total Cr (p<0.01) and free Cr (p<0.05). There were no significant differences between groups for performance during the cycle test, however, there were trends toward group by time interactions for performance enhancement in CrS relative to Pl, as total work (p=0.078) and work capacity (p=0.058) increased 3.8 ± 2.2% in CrS and decreased 0.5 ± 0.4% in Pl. It was concluded that short-term energy restriction resulted in decreased muscle Cr storage, and that Cr supplementation during energy restriction increased muscle Cr and CrP stores. Consumption of Cr allowed CrS to lose a significantly lower % FFM compared to Pl. Cr supplementation resulted in trends toward improved performance in CrS relative to Pl after energy restriction, but did not influence losses in body weight or %BF. / Master of Science

O objetivo do trabalho foi investigar o efeito da suplementação isolada de cafeína e bicarbonato de sódio sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática após simulação de luta de taekwondo. Para tanto, a presente tese foi dividida em estudo 1, com a suplementação de cafeína e estudo 2, com a suplementação de bicarbonato de sódio. Portanto, no estudo 1, o objetivo foi investigar o efeito da suplementação de cafeína sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática em simulação de luta de taekwondo. 10 atletas de taekwondo foram submetidos a duas sessões experimentais separadas por no mínimo de 48 horas entre elas. Nas duas visitas os atletas consumiram uma cápsula contendo cafeína (5 mg.kg-1 de massa corporal) ou placebo (celulose) uma hora antes da simulação da luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minuto de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço (PSE) antes e após cada round,e a frequência cardíaca (FC) e a contribuição dos sistemas energéticos foi estimada durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparados usando análise de variância de dois fatores (condição e tempo). Adicionalmente, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições cafeína e placebo. Os principais resultados indicam que: a suplementação de cafeína aumentou a contribuição do sistema glicolítico em relação ao placebo. Porém, a cafeína não melhorou o desempenho ou alterou a PSE, a FC ou a contribuição dos sistemas oxidativo e ATP-CP quando comparados ao placebo. Adicionalmente, nenhum índice da reativação parassimpática foi afetado pela suplementação de cafeína. No estudo 2, o objetivo do estudo foi investigar o efeito da suplementação de bicarbonato de sódio sobre a contribuição dos sistemas energéticos durante a simulação de luta de taekwondo. Para tanto, foram avaliados 9 atletas de taekwondo, os quais foram submetidos a duas condições experimentais, separadas por um mínimo de 48 horas entre elas. Nas duas visitas os atletas ingeriram uma cápsula contendo 0,03 g.kg-1 da massa corporal de NaHCO3- ou placebo (carbonato de cálcio), 90 minutos antes da simulação de luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minutos de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço antes e após cada round, a frequência cardíaca e a contribuição dos sistemas energéticos foram estimadas durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparadas usando análise de variância de dois fatores (condição e tempo). Além disso, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições NaHCO3 e placebo. Os principais resultados demonstraram que a suplementação de NaHCO3 aumentou a contribuição do sistema glicolítico e o tempo total de ataque em relação ao placebo. Porém, o NaHCO3 não alterou a FC, a PSE ou a contribuição dos sistemas oxidativo e ATP-CP durante a simulação de luta quando comparados ao placebo. Além disso, nenhum índice da reativação parassimpática foi afetado pela suplementação de NaHCO3 ou placebo / The aim of this study was to investigate the isolated effect of caffeine and sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a simulated taekwondo combat. Therefore, this thesis was divided in two studies: study 1 investigated the effect of caffeine, while study 2 investigated the effect of sodium bicarbonate. Thus, in study 1, the aim was to investigate the effect of caffeine supplementation on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a taekwondo combat. Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either 5 mg?kg-1 body mass of caffeine or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spend fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate and the estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated. Lactate concentration, rate of perceived of exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test in both caffeine and placebo conditions. The main results showed that caffeine ingestion increased the estimated glycolytic system when compared to placebo condition. However, caffeine ingestion did not alter the rate of perceived exertion, heart rate, estimated oxidative and ATP-PCr contribution or improve the performance in relation to placebo condition. Furthermore, caffeine ingestion did not influence post-exercise parasympathetic reactivation following a taekwondo simulation when compared to placebo condition. In study 2, the main aim of the study was to investigate the effect of sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during simulated taekwondo combat. Nine taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed 300 mg?kg-1 body mass of sodium bicarbonate or calcium bicarbonate (placebo) 90 minutes before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spent fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate, estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was calculated. Lactate concentration, rate of perceived exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test. The main results showed that sodium bicarbonate ingestion increased the lactate concentration, estimated glycolytic contribution and total attack time when compared with placebo condition. However, sodium bicarbonate ingestion did not influence heart rate, rate of perceived exertion, estimated oxidative and ATP-PCr contribution during combat simulation compared to placebo. Furthermore, no indices of parasympathetic reactivation were different between sodium bicarbonate and placebo conditions

O objetivo do trabalho foi investigar o efeito da suplementação isolada de cafeína e bicarbonato de sódio sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática após simulação de luta de taekwondo. Para tanto, a presente tese foi dividida em estudo 1, com a suplementação de cafeína e estudo 2, com a suplementação de bicarbonato de sódio. Portanto, no estudo 1, o objetivo foi investigar o efeito da suplementação de cafeína sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática em simulação de luta de taekwondo. 10 atletas de taekwondo foram submetidos a duas sessões experimentais separadas por no mínimo de 48 horas entre elas. Nas duas visitas os atletas consumiram uma cápsula contendo cafeína (5 mg.kg-1 de massa corporal) ou placebo (celulose) uma hora antes da simulação da luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minuto de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço (PSE) antes e após cada round,e a frequência cardíaca (FC) e a contribuição dos sistemas energéticos foi estimada durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparados usando análise de variância de dois fatores (condição e tempo). Adicionalmente, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições cafeína e placebo. Os principais resultados indicam que: a suplementação de cafeína aumentou a contribuição do sistema glicolítico em relação ao placebo. Porém, a cafeína não melhorou o desempenho ou alterou a PSE, a FC ou a contribuição dos sistemas oxidativo e ATP-CP quando comparados ao placebo. Adicionalmente, nenhum índice da reativação parassimpática foi afetado pela suplementação de cafeína. No estudo 2, o objetivo do estudo foi investigar o efeito da suplementação de bicarbonato de sódio sobre a contribuição dos sistemas energéticos durante a simulação de luta de taekwondo. Para tanto, foram avaliados 9 atletas de taekwondo, os quais foram submetidos a duas condições experimentais, separadas por um mínimo de 48 horas entre elas. Nas duas visitas os atletas ingeriram uma cápsula contendo 0,03 g.kg-1 da massa corporal de NaHCO3- ou placebo (carbonato de cálcio), 90 minutos antes da simulação de luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minutos de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço antes e após cada round, a frequência cardíaca e a contribuição dos sistemas energéticos foram estimadas durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparadas usando análise de variância de dois fatores (condição e tempo). Além disso, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições NaHCO3 e placebo. Os principais resultados demonstraram que a suplementação de NaHCO3 aumentou a contribuição do sistema glicolítico e o tempo total de ataque em relação ao placebo. Porém, o NaHCO3 não alterou a FC, a PSE ou a contribuição dos sistemas oxidativo e ATP-CP durante a simulação de luta quando comparados ao placebo. Além disso, nenhum índice da reativação parassimpática foi afetado pela suplementação de NaHCO3 ou placebo / The aim of this study was to investigate the isolated effect of caffeine and sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a simulated taekwondo combat. Therefore, this thesis was divided in two studies: study 1 investigated the effect of caffeine, while study 2 investigated the effect of sodium bicarbonate. Thus, in study 1, the aim was to investigate the effect of caffeine supplementation on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a taekwondo combat. Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either 5 mg?kg-1 body mass of caffeine or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spend fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate and the estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated. Lactate concentration, rate of perceived of exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test in both caffeine and placebo conditions. The main results showed that caffeine ingestion increased the estimated glycolytic system when compared to placebo condition. However, caffeine ingestion did not alter the rate of perceived exertion, heart rate, estimated oxidative and ATP-PCr contribution or improve the performance in relation to placebo condition. Furthermore, caffeine ingestion did not influence post-exercise parasympathetic reactivation following a taekwondo simulation when compared to placebo condition. In study 2, the main aim of the study was to investigate the effect of sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during simulated taekwondo combat. Nine taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed 300 mg?kg-1 body mass of sodium bicarbonate or calcium bicarbonate (placebo) 90 minutes before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spent fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate, estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was calculated. Lactate concentration, rate of perceived exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test. The main results showed that sodium bicarbonate ingestion increased the lactate concentration, estimated glycolytic contribution and total attack time when compared with placebo condition. However, sodium bicarbonate ingestion did not influence heart rate, rate of perceived exertion, estimated oxidative and ATP-PCr contribution during combat simulation compared to placebo. Furthermore, no indices of parasympathetic reactivation were different between sodium bicarbonate and placebo conditions

Mixed results, in terms of performance benefits, have been found when comparing carbohydrate (CHO) and carbohydrate-protein (CHO-P) supplementation during endurance exercise. Thus this study assessed performance from three different supplements (CHO-P, CHO, double carbohydrate [CHO-CHO]) as compared to a placebo (PLA) during a time trial (TT) run. Twelve male recreational runners (age = 32.4 ± 9.5 yrs; body mass index [BMI] = 22.7 ± 1.5 kg/m2; VO2max = 59.68 ± 7.53 mL/kg body weight; 100% white) individually completed four, 12-mile TT runs, 7-10 days apart, at about 75% of the their race pace. Dietary and physical activity consistency within the 24-hour time period prior to each run was controlled via individualized diet and activity prescriptions based off of the diet consumed and the physical activity engaged in prior to TT 1. Throughout each TT run, participants consumed a 600 mL load of one of the four aforementioned supplements. Supplement order was counterbalanced with a latin-square design. Endurance performance was measured by time to complete the 12-mile run, and time to complete the last 1.2 miles of the run, where participants were instructed to run at maximal effort, 100% race pace. A main effect of time occurred during the TTs for perceived exertion (RPE) and heart rate (HR). RPE (Borge 10-point scale) significantly increased from the mid-point of the TT to completion of the run (4.7 ± 0.7, 9.7 ± 0.9, p < 0.001); HR significantly increased from the start of the run to the start of the maximal effort, and was significantly higher at completion of the effort (84.4 ± 14.5 bpm, 166.0 ± 8.3 bpm, 178.8 ± 7.4 bpm, p < 0.001). No significant difference was found in overall time to complete the 12-mile run or maximal effort between the supplements (PLA = 88.6 ± 11.6 min, CHO = 89.1 ± 11.3 min, CHO-P = 89.1 ± 11.8 min, CHO-CHO = 89.6 ± 11.9 min; PLA = 8.3 ± 1.2 min, CHO = 8.2 ± 1.2 min, CHO-P = 8.2 ± 1.2 min, CHO-CHO = 8.4 ± 1.5 min). These findings suggest that type of supplementation (CHO, CHO-CHO, CHO-P) consumed during an endurance exercise bout has no influence on enhancing endurance performance in male recreational runners during TT runs less than 100 minutes in length.

Abstract The Effects of a Combined Supplementation of Creatine and Sodium Bicarbonate on Repeated Sprint Performance James Jeremy Barber There is well-established research that suggests both creatine and sodium bicarbonate are effective ergogenic aids. However, only one published study has examined the combined effects of creatine and sodium bicarbonate. The primary purpose of this study was to determine if a combined supplementation of creatine monohydrate and sodium bicarbonate would further enhance the well-documented effects of creatine supplementation alone on repeated sprint performance. Thirteen healthy and fit males (Mean age = 21.15 ± 0.65 years and mean VO2 max = 66.72 ± 5.78) participated in this experimental study using a double-blinded crossover study design in which each subject was used as his own control. All subjects completed 3 conditions, followed by a 3-week washout period between each condition: 1) Placebo (Pl; 5 g maltodextrin + 0.5 g/kg maltodextrin), 2) Creatine (Cr; 5 g + 0.5 g/kg maltodextrin), and 3) Creatine plus sodium bicarbonate (Cr+Sb; 5g + 0.5 g/kg sodium bicarbonate). Each condition was a 2-day supplementation. In the morning after each supplementation, peak power, RPP, mean power, RMP, fatigue index, and perceptions of fatigue and GI distress were assessed during six 10-second repeated Wingate tests. Blood bicarbonate, pH, and lactate were measured 5 minutes before testing and immediately after the last Wingate sprint. The main findings were; 1) Cr+Sb produced 7% greater relative peak power and 4.6% greater peak power values than placebo, and 2) Cr+Sb demonstrated the greatest attenuation of decline in relative peak power over six repeated sprints. However, in contrast to our hypotheses, no benefits from either supplementation were observed for relative mean power, fatigue index, and perception of fatigue. Considering that this current study found benefits from combining creatine and sodium bicarbonate, it suggests that combining the supplements may improve repeated sprint performance. Future research on a greater sample size, a specific athletic population, various exercise modes, and comparing results with a sodium bicarbonate alone supplementation would be beneficial in determining if this combined supplementation is worthwhile.

Made available in DSpace on 2015-04-17T15:03:03Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1056212 bytes, checksum: 97179266e33a5732de310daa2c8a7791 (MD5) Previous issue date: 2010-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Dietary supplements are widely consumed by exercise practitioners and athletes. Researchers have noted the inadequacy of such products, as well as the presence of androgens, increasing suspicion about their true composition. The objective of this research was to list and classify food supplements sold in retail outlets in Joao Pessoa, check the products suitability to existing laws; to analyze the effects in young rats subjected to exercise, caused by the chronic ingestion of supplements widely marketed on: food intake and body weight gain, levels of total testosterone, and body composition (fat percentage and lean mass). In a survey of descriptive and experimental field, at first, we identified the products sold in Joao Pessoa city, represented by pharmacies, specialized stores and supermarkets. We compared the composition and characteristics of supplements labeled with the minimal of composition and quality set by Ordinance 222/98 ANVISA. Products that were not included in the Ordinance were classified among categories according to their composition and/or its market name. In the experimental work, sixty young male Wistar rats were distributed into five groups (n = 12/group) (TC - trained control; SC sedentary control; ST1 supplemented/trained 1; ST2 - supplemented/trained 2; ST3 - supplemented/trained 3). By gavage, ST1, ST2 and ST3 received 2.5g of each supplement and TC and SC got filtered water. Animals weight and food intake were measured weekly. After eight weeks, animals were sacrificed and blood concentration of total testosterone were measured and carcasses fat and protein determination. A total of 945 different products were determined, most of them (43%) considered Foods for Physical Activity Practitioners (FPAP) and 28% of products forbidden in Brazilian market. Among the FPAP, none of them had all the legislation features, mainly because it contains, according to the products labeling, vitamins and minerals excess, or may not show the minimum amount of protein. Considering the studied supplements, 42% showed inadequate designation and 33% showed forbidden expressions. The results of experimental work showed that both exercise and supplementation promoted less weight gain (p<0.05). The exercise did not alter the levels of total testosterone, however, the three supplements promoted reduction of testosterone levels (p <0.001). Fat percentage of ST1, ST2 and ST3 groups showed two times higher than the TC group (p<0.001). TC showed the amount of total body protein higher (p<0.05) than the supplemented groups. The high inadequacy rate, mainly with vitamins and minerals excess and the lower proportion of labeled proteins, demonstrates the need for supplements control according to the law. The suitability assessment allows to see if the supplement or group of supplements containing the nutrients minimum levels to generate their expected impact, either in performance, health or nutrition. The data indicate that chronically supplements caused an increase of adipose tissue, lower gain muscle mass and lower weight gain, mainly because of the decreased secretion of testosterone. Similar results for the three supplements tested support the hypothesis that they contain androgens or their precursors. / Suplementos alimentares têm sido extensamente consumidos por praticantes de exercícios físicos e atletas. Pesquisadores têm observado a inadequabilidade da composição destes produtos, além de detectar a presença de andrógenos, aumentando a suspeita sobre sua verdadeira composição. O objetivo dessa pesquisa foi listar e classificar os suplementos alimentares comercializados nos pontos de venda de João Pessoa; verificar a adequabilidade dos produtos à legislação vigente; analisar os efeitos em ratos jovens submetidos a exercício físico, desencadeados pela ingestão crônica de suplementos amplamente comercializados sobre: o consumo alimentar e ganho de peso corporal; níveis de testosterona total; e, composição corporal (percentual de gordura e massa magra). Em uma pesquisa de campo descritiva e experimental, em um primeiro momento, identificou-se os produtos nos pontos de venda da cidade de João Pessoa-PB, representados por farmácias, lojas especializadas e supermercados. Comparou-se a composição e as características rotuladas dos suplementos com os fatores essenciais de composição e qualidade fixadas pela Portaria 222/98 da ANVISA. Os produtos que não se enquadravam na Portaria foram classificados em categorias de acordo com sua composição e/ou sua denominação de mercado. No trabalho experimental, distribuiu-se 60 ratos machos jovens Wistar em cinco grupos (n=12/grupo) (CT controle treinado; CS controle sedentário; ST1 treinado/suplementado 1; ST2 treinado/suplementado 2; ST3 treinado/suplementado 3). Por gavagem, ST1, ST2 e ST3 receberam 2,5g de cada suplemento e CT e CS receberam água filtrada. Semanalmente, registrou-se o peso e o consumo alimentar. Após oito semanas, realizaram-se dosagens de testosterona total e determinação de gordura e proteína das carcaças. Catalogou-se 945 produtos diferentes, a maior parte (43%) considerada Alimentos para Praticantes de Atividade Física (APAF) e 28% de produtos com comercialização proibida no Brasil. Dentre os APAF, nenhum apresentou todas as características exigidas pela legislação, principalmente por conter, de acordo com o rótulo dos produtos, excesso de vitaminas e minerais, ou não apresentar a quantidade mínima de proteínas. Entre os suplementos analisados 42% apresentavam denominação inadequada e 33% apresentaram expressões proibidas. Os resultados do trabalho experimental demonstraram que tanto o exercício como a suplementação promoveram menor ganho de peso (p<0,05). O exercício não alterou os níveis de testosterona total, entretanto, os três suplementos promoveram redução destes níveis (p<0,001). Os grupos ST1, ST2, ST3 apresentaram percentual de gordura duas vezes maior do que o grupo CT (p<0,001). CT apresentou quantidade de proteína corporal total maior (p<0,05) que os suplementados. Considerando-se o alto índice de inadequabilidade, principalmente quanto ao excesso de vitaminas e minerais e à menor proporção de proteínas rotuladas, demonstra-se a necessidade de controle e fiscalização desses produtos. A avaliação da adequabilidade da composição e das características rotuladas permite verificar se o suplemento ou grupo de suplementos contém os nutrientes mínimos para gerar seus efeitos esperados, seja na performance, na saúde ou na nutrição. Os dados encontrados indicam que cronicamente os suplementos causaram aumento de tecido adiposo, menor ganho de massa muscular e menor ganho de peso, provável consequência da menor secreção de testosterona. Os resultados similares para os três grupos reforçam a hipótese de que os suplementos continham andrógenos ou seus precursores.