Effect of Resistance Training With Total and Partial Blood Flow Restriction on Biomarkers of Oxidative Stress and Apoptosis in Untrained Men.

Introduction: The characterization of immune and oxidative stress responses to acute and chronic exercise training is important because it may aid in the safety and dose-response prescription of resistance training (RT) in many populations. Purpose: The present study compared changes in acute oxidative stress and markers of apoptosis in immune cells before and after 8 weeks of low-load RT with total or partial blood flow restriction (BFR) versus high-load traditional RT. Methods: Twenty-seven untrained men were randomly divided into three groups: traditional RT [75% one-repetition maximum (1-RM)], RT with partial (20% 1-RM), and total BFR (20% 1-RM). Over an 8-week period, participants performed six sets of arm curls until failure with 90 seconds of recovery for 3 days/week. Blood samples were obtained before and after the first and last training sessions. Results: Data indicated that all training groups showed similar increases in muscular strength (p < 0.001), reduction in mitochondrial membrane potential (MMP) after exercise in neutrophils (p < 0.001), and increase in caspase-3 activity after exercise (p < 0.001). Traditional RT and total BFR showed increased plasma lipid peroxidation (p < 0.001) and protein carbonyls (p < 0.001) and lower levels of reduced glutathione (GSH) (p < 0.001) after exercise. No change was observed in oxidative stress biomarkers in response to partial BFR (p > 0.05). Conclusion: Data show that RT with partial BFR can increase muscular strength but still does not augment biomarkers of oxidative stress in untrained men. In addition, RT with total BFR promoted similar responses of oxidative stress and markers of immune cell apoptosis versus traditional RT.

The Goal Scale: A New Instrument to Measure the Perceived Exertion in Soccer (Indoor, Field, and Beach) Players.

The rating of perceived exertion (RPE) can be used to monitor the exercise intensity during laboratory and specific tests, training sessions, and to estimate the internal training load of the athletes. The aim of the present study was to develop and validate a specific pictorial perceived exertion scale for soccer players (indoor, field, and beach soccer) called GOAL Scale. The pictorial GOAL Scale (six drawings; 1 "low exertion" to 6 "exhaustion") was validated for twenty under-17 soccer players (16.4 ± 0.68 years; 175.4 ± 9 cm; 66.4 ± 7.7 kg; % fat mass 12.4 ± 3.3). In the validation phase, the athletes were evaluated in a progressive protocol involving stimuluses of 3 min with 1 min for the rest into the stages until the voluntary exhaustion in Maximal Cardiopulmonary Effort Test (MCET), and in the Yo Yo Intermittent Recovery Test - Level 1 (Yo-Yo). The RPE identified by the GOL Scale, by the Borg Scale 6 - 20 and by the Cavasini Scale, as well as the heart rate (HR), perceptual of the heart rate (%HRmax) and the blood lactate concentration ([La]) were immediately evaluated after each stage of both tests. Spearman's correlation coefficient (p < 0.05) was used. Construct scale validity was examined by regressing GOAL Scale against Borg Scale 6 - 20 and Cavasini Scale and concurrent scale validity was investigated by regressing GOAL Scale against HR, beats/min and blood lactate concentration (mmol/L) during two progressive tests. There was a significant correlation values of the GOAL Scale with Borg Scale (r = 0.93; r = 0.88), Cavasini Scale (r = 0.91; r = 0.90), %HRmax (r = 0.91; r = 0,86), HR (r = 0.87; r = 0.83) and lactate (r = 0.68; r = 0.83) during tests (Maximal Incremental Cardiopulmonary Test and Yo-Yo test, respectively). The results evidenced concurrent and construct validity of the GOAL Scale across a wide range of exercise intensity. The absence of verbal anchors makes the use of this instrument to soccer, futsal and beach soccer athletes of different languages and different literacy levels possible.

Comparison of perceptual responses between different upper-body sprint interval exercise protocols.

This study examined the perceptual responses to various upper-body sprint interval exercise (SIE) protocols matched for total work and work/rest ratio. Fourteen active men (24 ±â€¯4 years, BMI = 26.2 ±â€¯2.7 kg/m2, body fat = 11.5 ±â€¯4.4%) participated in 3 all-out SIE protocols consisting of battling rope exercise: P10:30 (12 × 10-s bouts with 30-s recovery); P15:45 (8 × 15-s bouts with 45 s recovery); and P30:90 (4 × 30-s bouts with 90-s recovery). During exercise, affective valence (FS +5 to -5), arousal (FAS 1-6), rating of perceived exertion (RPE 6-20), and heart rate (HR) were assessed. Post-exercise, enjoyment, self-efficacy, and intentions were measured. Results revealed a significant decline in FS (p = .02; partial eta squared [η2p] = 0.27) and a progressive increase in FAS (p = .001; η2p = 0.86), RPE (p = .001; η2p = 0.88), and HR (p = .001; η2p = 0.94), but no protocol X time interaction. Affective valence reached a nadir at values equal to -0.36 ±â€¯3.41 (Cohen's d = -0.49), -0.43 ±â€¯3.75 (Cohen's d = -0.44), and - 0.93 ±â€¯3.49 (Cohen's d = -0.56) in response to P10:30, P15:45, and P30:90, respectively. There were no differences between protocols for enjoyment, intention, or self-efficacy. A negative relationship exhibited between FS and RPE was moderated by participants' tolerance of exercise intensity (ß = 1.84, p < .05). Further, the association between FS and future intention was mediated by self-efficacy. Overall, upper-body SIE protocols exhibit similar perceptual responses when volume and work to rest ratio (1:3) are matched. Tolerance of exercise intensity may be used to predict changes in FS during SIE.

Systematic review of means and methods of practical influence on taekwon-do training / Revisão sistemática dos meios e métodos de influência prática no treinamento do taekwon-do

ABSTRACT The investigation of means and methods of practical influence can assist in training and allow for improved sport performance. Therefore, the objective of this study was to review in the literature methods and means with practical influence on Taekwon-Do specifically. A systematic review was conducted with English/Portuguese descriptors, namely martial arts/artes marciais, exercise/exercícios, physical fitness/aptidão física and athletic performance/desempenho esportivo, on Portal Capes, Sport Discus, Lilacs, Medline and PubMed databases. After application of inclusion and exclusion criteria, 12 studies were selected. In the studies analyzed, 21 types of training means and 19 types of training methodologies were identified. Among the results, there is an evident use of special means, mainly exercises with kicks and the interval method, with high intensity, to prepare athletes to the physiological demands of combat and to develop their aerobic and anaerobic systems.

RESUMO A investigação de meios e métodos de influência prática podem auxiliar o treinamento e possibilitar melhora do desempenho esportivo. Portanto, o objetivo deste trabalho foi revisar na literatura os métodos e meios de influência prática específicos para a modalidade Taekwon-Do. Foi realizada uma revisão sistemática com os descritores em inglês/português: martial arts/artes marciais, exercise/exercícios, physical fitness/aptidão física e athletic performance/desempenho esportivo nas bases de dados Portal Capes, Sport Discus, Lilacs, Medline e PubMed. Foram consideradas publicações em português, espanhol e inglês. Após a aplicação de critérios de inclusão e exclusão, foram selecionados 12 estudos. Nos estudos avaliados, foram identificados 21 tipos de meios de treinamento e 19 tipos de metodologias de treinamento. Entre os resultados, evidencia-se a utilização de meios especiais, principalmente o trabalho com chutes e o método intervalado, com elevada intensidade, para preparar os atletas às demandas fisiológicas do combate e desenvolver os sistemas aeróbio e anaeróbio.

Oxidative stress and antioxidant status response of handball athletes: implications for sport training monitoring.

The chronic exposure to regular exercise training seems to improve antioxidant defense systems. However, the intense physical training imposed on elite athletes may lead to overtraining associated with oxidative stress. The purpose of the present study was to investigate the effect of different training loads and competition on oxidative stress, biochemical parameters and antioxidant enzymatic defense in handball athletes during 6-months of monitoring. Ten male elite handball athletes were recruited to the study. Blood samples were collected four times every six weeks throughout the season. During most intense periods of training and competitions there were significant changes in plasma indices of oxidative stress (increased TBARS and decreased thiols). Conversely, chronic adaptations to exercise training demonstrated a significant protective effect against oxidative stress in erythrocyte (decrease in TBARs and carbonyl group levels). Erythrocyte antioxidant enzyme activities were significantly increased, suggesting a training-induced antioxidant adaptation. Biomarkers of skeletal muscle damage were significantly increased during high-intensity training period (creatine kinase, lactate dehydrogenase and aspartate aminotransferase). No significant changes were observed in plasma IL-6, TNF-α and uric acid, whereas a significant reduction was found in the IL-1ß concentration and gamma-glutamyl transferase activity. Oxidative stress and antioxidant biomarkers can change throughout the season in competitive athletes, reflecting the physical stress and muscle damage that occurs as the result of competitive handball training. In addition, these biochemical measurements can be applied in the physiological follow-up of athletes.

Combined astaxanthin and fish oil supplementation improves glutathione-based redox balance in rat plasma and neutrophils.

The present study aimed to investigate the effects of daily (45 days) intake of fish oil (FO; 10mg EPA/kg body weight (BW) and 7 mg DHA/kg BW) and/or natural ASTA (1mg ASTA/kg BW) on oxidative stress and functional indexes of neutrophils isolated from Wistar rats by monitoring superoxide (O(2)(-)), hydrogen peroxide (H(2)O(2)), and nitric oxide (NO()) production compared to the progression of auto-induced lipid peroxidation and Ca(2+) release in activated neutrophils. Furthermore, phagocytic capacity, antioxidant enzyme activities, glutathione-recycling system, and biomarkers of lipid and protein oxidation in neutrophils were compared to the redox status. Our results show evidence of the beneficial effects of FO+ASTA supplementation for immune competence based on the redox balance in plasma (significant increase in GSH-dependent reducing power), non-activated neutrophils (increased activity of the glutathione-recycling enzymes GPx and GR) and PMA-activated neutrophils (lower O(2)(-), H(2)O(2), and NO() generation, reduced membrane oxidation, but higher phagocytic activity). Combined application of ASTA and FO promoted hypolipidemic/hypocholesterolemic effects in plasma and resulted in increased phagocytic activity of activated neutrophils when compared with ASTA or FO applied alone. In PMA-activated neutrophils, ASTA was superior to FO in exerting antioxidant effects. The bulk of data reinforces the hypothesis that habitual consumption of marine fish (e.g. salmon, which is a natural source of both astaxanthin and fish oil) is beneficial to human health, in particular by improving immune response and lowering the risk of vascular and infectious diseases.

Combined fish oil and astaxanthin supplementation modulates rat lymphocyte function.

PURPOSE: Higher intakes of n-3 polyunsaturated fatty acids that are abundant in marine fishes have been long described as a "good nutritional intervention" with increasing clinical benefits to cardiovascular health, inflammation, mental, and neurodegenerative diseases. The present study was designed to investigate the effect of daily fish oil (FO-10 mg EPA/kg body weight (BW) and 7 mg DHA/kg BW) intake by oral gavage associated with the antioxidant astaxanthin (ASTA-1 mg/kg BW) on the redox metabolism and the functional properties of lymphocytes from rat lymph nodes. METHODS: This study was conducted by measurements of lymphocyte proliferation capacity, ROS production [superoxide (O2(•-)) and hydrogen peroxide (H2O2)], nitric oxide (NO(•)) generation, intracellular calcium release, oxidative damage to lipids and proteins, activities of major antioxidant enzymes, GSH/GSSG content, and cytokines release. RESULTS: After 45 days of FO + ASTA supplementation, the proliferation capacity of activated T- and B-lymphocytes was significantly diminished followed by lower levels of O2(•-), H2O2 and NO(•) production, and increased activities of total/SOD, GR and GPx, and calcium release in cytosol. ASTA was able to prevent oxidative modification in cell structures through the suppression of the oxidative stress condition imposed by FO. L: -selectin was increased by FO, and IL-1ß was decreased only by ASTA supplementation. CONCLUSION: We can propose that association of ASTA with FO could be a good strategy to prevent oxidative stress induced by polyunsaturated fatty acids and also to potentiate immuno-modulatory effects of FO.

Influência de três intervalos entre series sobre o desempenho neuromuscular no treinamento com pesos / Influence of three intervals between series on neuromuscular performance in weight training

o intervalo de repouso (IR) entre as séries e exercícios pode afetar a resposta aguda hormonal, metabólica, cardiovascular e neuromuscular ao treinamento com pesos (TP). Objetivo: comparar a influência de três diferentes IR entre as séries no desempenho neuromuscular no supino reto e leg press 45º durante quatro séries consecutivas em mulheres atletas de handebol. Métodos: foram avaliadas sete atletas (17,29 + 0,76 anos; massa corporal 69,7 + 10,5kg; estatura 168,6 + 10,3cm) com experiência prévia no TP. Todas as atletas participaram de seis sessões experimentais de treinamento separadas por 48 horas de intervalo durante 4 semanas. Inicialmente, foi realizado o três de 1RM nos exercícios de supino reto e leg press 45º separados por 48 horas de intervalo. Durante cada teste, quatro séries de supino reto e leg press 45º foram executas até a exaustão a 75% de 1RM. O IR entre as séries foi de um, três e cinco minutos divididos aleatoriamente durante os testes. O número total de repetições (RT) completadas e a sustentabilidade das repetições (SR) foram comparados entre as condições de IR e exercícios. A análise estatística foi Análise de Variância Fatorial (ANOVA) 3x4 de medidas repetidas (p<0,05). Resultados: Para o supino reto, os resultados evidenciaram declínio significativo na SR entre a primeira e a quarta séries com um e três minutos de IR. O intervalo de cinco minutos resultou em TR significativamente maior durante quatro séries comparado a intervalo de um minuto. Entretanto, SR não foi afetada durante as quatro séries com cinco minutos de IR. Nenhuma diferença significativa foi encontrada para o leg press 45º. Conclusão: Dados indicam que o desempenho neuromuscular no supino reto foi menor com IR menor entre séries. IR entre três e cinco minutos em TP mantem o volume da sessão de treinamento para o exercício de supino reto. Por outro lado, IR menor que três minutos promovem redução do número de repetições no leg press 45º.

Background: the length of rest interval (RI) between sets and exercises may affect hormonal, metabolic, cardiovascular and neuromuscular response on acute resistance training. Purpose: to compare the influence of three different RI conditions on bench press and leg press 45º performance over four consecutive sets in female handball players. Methods: we evaluated seven healthy female handball players (17.29 + 0.76 years old; body mass 69.7 + 10.5Kg; body height 168.6 + 10.3cm) with resistance training experience. All subjects performed six session of tests with 48 hours interval over a period of four weeks. During each test session, four sets of the bench press and leg press 45º were performed until exhaustion with 75% of 1 repetition maximum (1RM). The RI among sets was one minute; three minutes and five minutes by random assessment. The total repetitions (TR) completed and the sustainability of repetitions (SR) was compared among rest conditions and between exercises. Statistical analysis was the Two Way ANOVA for repeated measures (p<.05) for exercises and RI. Methods: we evaluated seven healthy female handball players (17.29 + 0.76 years old; body mass 69.7 + 10.5Kg; body height 168.6 + 10.3cm) with resistance training experience. All subjects performed six session of tests with 48 hours interval over a period of four weeks. During each test session, four sets of the bench press and leg press 45º were performed until exhaustion with 75% of 1 repetition maximum (1RM)...Conclusion: data presented that neuromuscular response in bench press was lower with shorter RI length between sets. RI between three and five minutes keeps the totalsession volume in bench press exercise. On the other hand the RI shorter than three minutes will reduce the number of repetitions on leg press 45º.

Cytokines and oxidative stress status following a handball game in elite male players.

BACKGROUND: Handball is considered an intermittent sport that places an important stress on a player's aerobic and anaerobic metabolism. However, the oxidative stress responses following a handball game remain unknown. We investigated the responses of plasma and erythrocyte antioxidant system and oxidative stress biomarkers following a single handball game. METHODS: Fourteen male elite Brazilian handball athletes were recruited in the present study. Blood samples were taken before, immediately, and 24 hours after the game. RESULTS: After the game and during 24 hours of recovery, the concentration of all oxidative stress indices changed significantly in a way indicating increased oxidative stress in the blood (thiol groups and reduced glutathione decreased, whereas TBARS and plasma antioxidant capacity was increased) as well as in erythrocyte (increased levels of TBARS and protein carbonyls). Erythrocyte antioxidant enzyme activities were also significantly changed by handball. Muscle damage indices (creatine kinase and lactate dehydrogenase) increased significantly after exercise. In addition, IL-6 increased after the game, whereas TNF-α decreased during recovery. CONCLUSION: This study demonstrates that a single handball game in elite athletes induces a marked state of oxidative stress evidenced by the oxidative modification in plasma and erythrocyte macromolecules, as well as by changes in the enzymatic and nonenzymatic antioxidant system.

ROS production in neutrophils from alloxan-induced diabetic rats treated in vivo with astaxanthin.

BACKGROUND: Astaxanthin (ASTA) is a carotenoid which has powerful antioxidant, anti-tumor, anti-diabetic, anti-inflammatory and cardioprotective properties. The present study investigated the effect of daily ASTA intake on oxidative stress and the functional properties of neutrophils from alloxan-induced diabetic rats. METHODS: Neutrophils isolated from ASTA-fed rats (30days, 20mg ASTA/kg of body weight - BW) induced to diabetes by alloxan treatment (i.p. 75mg/BW) were assessed by: production of superoxide and hydrogen peroxide, nitric oxide, basal calcium release, oxidative damage (TBARS and carbonyls content), and activities of major antioxidant enzymes. RESULTS: Our results show that diabetes promotes a significant oxidative stress in neutrophils. The production of superoxide was significantly increased in neutrophils from diabetic rats and treatment with ASTA was not effective in reducing superoxide levels. At the same time, a reduction in the activity of total superoxide dismutase enzyme was observed, which was not restored after treatment with ASTA. At resting conditions, neutrophils have a higher basal production of hydrogen peroxide, which is enhanced following PMA-stimulation. Treatment with ASTA does not restore values to the basal levels. The indicators of oxidative damage to biomolecules showed that diabetic rats significantly increased the lipid and protein damage, but this change was reversed after treatment with ASTA. CONCLUSION: Our results show that diabetes condition promotes a marked oxidative stress in neutrophils and treatment with ASTA for 30days at a dose of 20mg/kg of BW partially reverses those deleterious effects.

ROS production in neutrophils from alloxan-induced diabetic rats treated in vivo with astaxanthin

Astaxanthin (ASTA) is a carotenoid which has powerful antioxidant, anti-tumor, anti-diabetic, anti-inflammatory and cardioprotective properties. The present study investigated the effect of daily ASTA intake on oxidative stress and the functional properties of neutrophils from alloxan-induced diabetic rats.Neutrophils isolated from ASTA-fed rats (30 days, 20 mg ASTA/kg of body weight — BW) induced to diabetes by alloxan treatment (i.p. 75 mg/BW) were assessed by: production of superoxide and hydrogen peroxide, nitric oxide, basal calcium release, oxidative damage (TBARS and carbonyls content), and activities of major antioxidant enzymes.Our results show that diabetes promotes a significant oxidative stress in neutrophils. The production of superoxide was significantly increased in neutrophils from diabetic rats and treatment with ASTA was not effective in reducing superoxide levels. At the same time, a reduction in the activity of total superoxide dismutase enzyme was observed, which was not restored after treatment with ASTA. At resting conditions, neutrophils have a higher basal production of hydrogen peroxide, which is enhanced following PMAstimulation. Treatment with ASTA does not restore values to the basal levels. The indicators of oxidative damage to biomolecules showed that diabetic rats significantly increased the lipid and protein damage, but this change was reversed after treatment with ASTA. Our results show that diabetes condition promotes a marked oxidative stress in neutrophils and treatment with ASTA for 30 days at a dose of 20 mg/kg of BW partially reverses those deleterious effects.

Testosterone suppresses oxidative stress in human neutrophils.

The in vitro effect of testosterone on human neutrophil function was investigated. Blood neutrophils from healthy male subjects were isolated and treated with 10 nM, 0.1 and 10 microM testosterone for 24 h. As compared with untreated cells, the testosterone treatment produced a significant decrease of superoxide production as indicated by the measurement of extra- and intracellular superoxide content. An increment in the production of nitric oxide was observed at 0.1 and 10 microM testosterone concentrations, whereas no effect was found for 10 nM. Intracellular calcium mobilization was significantly increased at 10 nM, whereas it was reduced at 10 microM testosterone. There was an increase in phagocytic capacity at 10 nM and a decrease of microbicidal activity in neutrophils treated with testosterone at 10 microM. Glutathione reductase activity was increased by testosterone treatment, whereas no effect was observed in other antioxidant enzyme activities. An increase in the content of thiol groups was observed at all testosterone concentrations. Lipid peroxidation in neutrophils evaluated by levels of TBARS was decreased at 10 nM and 0.1 microM testosterone. These results indicate the antioxidant properties of testosterone in neutrophils as suggested by reduction of superoxide anion production, and lipid peroxidation, and by the increase in nitric oxide production, glutathione reductase activity and the content of thiol groups. Therefore, the plasma levels of testosterone are important regulators of neutrophil function and so of the inflammatory response.

Astaxanthin ameliorates the redox imbalance in lymphocytes of experimental diabetic rats.

Diabetes mellitus is a syndrome of impaired insulin secretion/sensitivity and frequently diagnosed by hyperglycemia, lipid abnormalities, and vascular complications. The diabetic 'glucolipotoxicity' also induces immunodepression in patients by redox impairment of immune cells. Astaxanthin (ASTA) is a pinkish-orange carotenoid found in many marine foods (e.g. shrimp, crabs, salmon), which has powerful antioxidant, photoprotective, antitumor, and cardioprotective properties. Aiming for an antioxidant therapy against diabetic immunodepression, we here tested the ability of prophylactic ASTA supplementation (30 days, 20 mg ASTA/kg BW) to oppose the redox impairment observed in isolated lymphocytes from alloxan-induced diabetic Wistar rats. The redox status of lymphocytes were thoroughly screened by measuring: (i) production of superoxide (O(2)(-)), nitric oxide (NO), and hydrogen peroxide (H(2)O(2)); (ii) cytosolic Ca(2+); (iii) indexes of oxidative injury; and (iv) activities of major antioxidant enzymes. Hypolipidemic and antioxidant effects of ASTA in plasma of ASTA-fed/diabetic rats were apparently reflected in the circulating lymphocytes, since lower activities of catalase, restored ratio between glutathione peroxidase and glutathione reductase activities and lower scores of lipid oxidation were concomitantly measured in those immune cells. Noteworthy, lower production of NO and O(2)(-) (precursors of peroxynitrite), and lower cytosolic Ca(2+) indicate a hypothetical antiapoptotic effect of ASTA in diabetic lymphocytes. However, questions are still open regarding the proper ASTA supplementation dose needed to balance efficient antioxidant protection and essential NO/H(2)O(2)-mediated proliferative capacities of diabetic lymphocytes.

Astaxanthin ameliorates the redox imbalance in lymphocytes of experimental diabetic rats

Diabetes mellitus is a syndrome of impaired insulin secretion/sensitivity and frequently diagnosed by hyperglycemia, lipid abnormalities, and vascular complications. The diabetic 'glucolipotoxicity' also induces immunodepression in patients by redox impairment of immune cells. Astaxanthin (ASTA) is a pinkish-orange carotenoid found in many marine foods (e.g. shrimp, crabs, salmon), which has powerful antioxidant, photoprotective, antitumor, and cardioprotective properties. Aiming for an antioxidant therapy against diabetic immunodepression, we here tested the ability of prophylactic ASTA supplementation (30 days, 20mg ASTA/kg BW) to oppose the redox impairment observed in isolated lymphocytes from alloxan-induced diabetic Wistar rats. The redox status of lymphocytes were thoroughly screened by measuring: (i) production of superoxide (O2•-), nitric oxide (NO•), and hydrogen peroxide (H2O2); (ii) cytosolic Ca2+; (iii) indexes of oxidative injury; and (iv) activities of major antioxidant enzymes. Hypolipidemic and antioxidant effects of ASTA in plasma of ASTA-fed/diabetic rats were apparently reflected in the circulating lymphocytes, since lower activities of catalase, restored ratio between glutathione peroxidase and glutathione reductase activities and lower scores of lipid oxidation were concomitantly measured in those immune cells. Noteworthy, lower production of NO and O2•- (precursors of peroxynitrite), and lower cytosolic Ca2+ indicate a hypothetical antiapoptotic effect of ASTA in diabetic lymphocytes. However, questions are still open regarding the proper ASTA supplementation dose needed to balance efficient antioxidant protection and essential NO•/H2O2-mediated proliferative capacities of diabetic lymphocytes.

Correlação entre porcentagem de gordura e índice de massa corporal de freqüentadores de academia de ginástica / Correlation between body fat porcentage and body mass index of fitness center participants

O índice de massa corporal (IMC) é freqüentemente recomendado para estimar o estado nutricional de adultos, entretanto esta técnica não prediz a quantidade de gordura corporal, podendo ser questionável a sua utilização para o diagnóstico de sobrepeso e obesidade. Nesse sentido, o objetivo do presente estudo foi verificar a correlação existente entre a porcentagem de gordura obtida por equações preditivas por meio da medida de espessura de dobras cutâneas Jackson & Pollock, 1978; Jackson et al. 1980; para densidade corporal; seguidas de Siri et al. 1956, para porcentagem de gordura e o IMC de freqüentadores de uma rede de academias de ginástica da cidade de São Paulo. Foram selecionados 799 alunos, aleatoriamente, sendo 363homens e 436 mulheres, entre 20 e 49,9 anos de idade. Foram realizadas medidas de massa e estatura utilizando-se balanças da marca Toledo e Estadiômetros da marca Sanny®; as medidas de dobras cutâneas foram realizadas seguindo-se a padronização descrita pelos autores das equações preditivas, utilizando-se adipômetros científicos da marca Sanny®. Os resultados obtidos na correlação linear de Pearson, entre a porcentagem de gordura e o IMC foram estatisticamente significantes para ambos os sexos: r=0,762 (p=0,000) para os homens e r=0,824 (p=0,000) para as mulheres. Considerando que as equações preditivas de gordura corporal utilizadas no presente estudo são generalizadas e teoricamente adequadas aos sujeitos avaliados podemos concluir que, embora tenha havido elevada correlação entre as variáveis, o IMC não foi um bom preditor do estado nutricional, pois apresentou grande discrepância no diagnóstico de sobrepeso e obesidade quando comparado à porcentagem de gordura, além de uma baixa sensibilidade, indicando grande possibilidade de diagnósticos falsos negativos.

The body mass index (BMI) is often recommended for estimating adults nutritional status; however, this index doesn’t measure body fat content, and its utility for overweight and obesity diagnose can be questionable. The aim of this study was to verify the correlation between body fat percentage by predictive equation using skinfold thickness (Jackson & Pollock, 1978; Jackson et al. 1980; for body density; and Siri et al. 1956; for body fat), and the BMI of fitness center users in São Paulo. 363 men and 436 women were taken part in the study, aged 20 – 49.9, randomly selected. It was performed weight and height measures through scales of Toledo® and Sanny® stadiometer; skinfold thickness measures were performed using standardization of predictive equation described by their own authors, with Sanny® skinfold calipers. The results showed by Pearson correlation, between fat percentage and BMI, demonstrated a significant valuefor both genders: r=0.762 (p=0.000) for men and r=0.824 (p=0.000) for women. Considering the data, although there was a high correlation between the variables, the BMI was not a good predictor of nutritional status. It has demonstrated high discrepancy in diagnose of overweight and obesity, when compared to body fat, with low sensibility, suggesting that there is a strong possibility to detect false negative cases.

Resposta sérica de testosterona e triiodotironina pós-treinamento intenso com pesos / Responses of serum testosterone and triiodotironine after intense resistance training

Introdução: as respostas adaptativas conduzidas pelo treinamento com pesos são em grande parte influenciadas pelo incremento na resposta aguda dos hormônios endógenos anabólicos. Objetivo: o propósito deste estudo foi determinar o efeito agudo do treinamento com pesos em circuito na resposta de testosterona (Tt) e triiodotironina (T3) em adultosjovens treinados. Métodos: foram avaliados oito indivíduos (22,1+2,06 anos) experientes em treinamento com pesos (TP), com pelo menos 12 meses de atividade (78,4+9,97 kg; 176,25+5,49 cm; e IMC 25,18+2,44 Kg/m²). A sessão de exercícios incluiu exercícios para membros inferiorese superiores para diferentes grupamentos musculares até a exaustão (3 séries; 6RM; em circuito alternando segmentos; intervalo de 10-20 segundos entre exercícios) com carga estipulada pelo teste de repetições máximas no dia anterior. A concentração hormonal sérica foi determinada pré e pós-treinamento, imediatamente após (T0), 20 (T20), 40 (T40) e 60 minutos (T60). A estatísticadescritiva foi feita pelo teste One Way Anova (p<0,05) e diferença porcentual (Δ%). Resultados: Os resultados analisados evidenciaram significativo incremento na concentração de Tt (29,42%) imediatamente após o exercício (repouso-T0), com decréscimo significativo (26,47%) entre T0 e T60 após o exercício. Nenhuma diferença significativa foi encontrada entre repouso e T20, T40e T60 após o treinamento. Da mesma maneira, nenhuma alteração significativa foi observada noT3 sérico em todas as mensurações que tendeu a estabilidade pós-treinamento. Conclusões: Os dados sugerem que o treinamento com pesos em circuito de alta intensidade e curtos períodosde intervalo entre as séries pode elevar a concentração de Tt após o exercício.

Introduction: The adaptations addressed by resistance training are influenced by acute endogenous anabolic hormones responses Purpose: The propouse of this study was determine the effect of resistance training (RT) on acute response of serum Testosterone (Tt)and Triiodothyronine (T3) in young trained men. Methods: We evaluated eight healthy male (22.,1+2.06 years old), with 12-month RT experience (78,4+9,97 Kg; 176,25+5,49 cm; andBMI 25,18+2,44 Kg/m²). The resistance training included exercises for lower and upper limbs in circuit exercise training until exhaustion (3 sets; 6RM in circuit, alternating upper and lower limbs; rest time between sets and exercises was 10-20s) with work load determined for maximal repetitions one day before test. Serum hormone was determined pre and post-exercise;immediately after exercises (T0), 20 (T20), 40 (T40) and 60 minutes (T60). Absolute values were analyzed by One Way Anova (p<.05) and Δ%. Results: Analysis evidenced significant increase on serum Tt (29,42%) immediately after exercise (rest-T0), with significant decrease (26,47%) between T0 and T60. No differences were found from rest to T20, T40 and T60. Also no significant change was observed on T3 at all measurements suggesting stability post-exercise.Conclusion: Data suggests that high-intensity circuit resistance training with short rest period may increase Tt concentration post-exercise.