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In contrast to the effect of nutritional intervention on postexercise muscle protein synthesis, little is known about the potential to modulate protein synthesis during exercise. This study investigates the effect of protein coingestion with carbohydrate on muscle protein synthesis during resistance-type exercise. Ten healthy males were studied in the evening after they consumed a standardized diet throughout the day. Subjects participated in two experiments in which they ingested either carbohydrate or carbohydrate with protein during a 2-h resistance exercise session. Subjects received a bolus of test drink before and every 15 min during exercise, providing 0.15 g * [kg.sup.-1] * [h.sup.-1] carbohydrate with (CHO + PRO) or without (CHO) 0.15 g * [kg.sup.-1] * [h.sup.-1] t protein hydrolysate. Continuous intravenous infusions with L-[ring-[sup.13[C].sub.6]]phenylalanine and L-[ring-[sup.2.[H].sub.2]]tyrosine were applied, and blood and muscle biopsies were collected to assess whole body and muscle protein synthesis rates during exercise. Protein coingestion lowered whole body protein breakdown rates by 8.4 [+ or -] 3.6% (P = 0.066), compared with the ingestion of carbohydrate only, and augmented protein oxidation and synthesis rates by 77 [+ or -] 17 and 33 [+ or -] 3%, respectively (P < 0.01). As a consequence, whole body net protein balance was negative in CHO, whereas a positive net balance was achieved after the CHO + PRO treatment (-4.4 [+ or -] 0.3 vs. 16.3 [+ or -] 0.4 [micro]mol phenylalanine * [kg.sup.-1] * [h.sup.-1], respectively; P < 0.01). In accordance, mixed muscle protein fractional synthetic rate was 49 [+ or -] 22% higher after protein coingestion (0.088 [+ or -] 0.012 and 0.060 [+ or -] 0.004%/h in CHO + PRO vs. CHO treatment, respectively; P < 0.05). We conclude that, even in a fed state, protein coingestion stimulates whole body and muscle protein synthesis rates during resistance-type exercise. nutrition; amino acids; muscle anabolism

The present study was designed to assess the impact of coingestion of various amounts of carbohydrate combined with an ample amount of protein intake on postexercise muscle protein synthesis rates. Ten healthy, fit men (20 [+ or -] 0.3 yr) were randomly assigned to three crossover experiments. After 60 min of resistance exercise, subjects consumed 0.3 g*[kg.sup.-1]*[h.sup.-1] protein hydrolysate with 0, 0.15, or 0.6 g*[kg.sup.-1]*[h.sup.-1] carbohydrate during a 6-h recovery period (PRO, PRO + LCHO, and PRO + HCHO, respectively). Primed, continuous infusions with L-[[ring-.sup.13][C.sub.6]]phenylalanine, L-[[ring-.sup.2][H.sub.2]]tyrosine, and [6,6-[sup.2][H.sub.2]]glucose were applied, and blood and muscle samples were collected to assess whole body protein turnover and glucose kinetics as well as protein fractional synthesis rate (FSR) in the vastus lateralis muscle over 6 h of postexercise recovery. Plasma insulin responses were significantly greater in PRO + HCHO compared with PRO + LCHO and PRO (18.4 [+ or -] 2.9 vs. 3.7 [+ or -] 0.5 and 1.5 [+ or -] 0.2 U*6 [h.sup.1]*[1.sup.-1], respectively, P < 0.001). Plasma glucose rate of appearance ([R.sub.a]) and disappearance (Ra) increased over time in PRO + HCHO and PRO + LCHO, but not in PRO. Plasma glucose [R.sub.a] and [R.sub.d] were substantially greater in PRO + HCHO vs. both PRO and PRO + LCHO (P < 0.01). Whole body protein breakdown, synthesis, and oxidation rates, as well as whole body protein balance, did not differ between experiments. Mixed muscle protein FSR did not differ between treatments and averaged 0.10 [+ or -] 0.01, 0.10 [+ or -] 0.01, and 0.11 [+ or -] 0.01%/h in the PRO, PRO + LCHO, and PRO + HCHO experiments, respectively. In conclusion, coingestion of carbohydrate during recovery does not further stimulate postexercise muscle protein synthesis when ample protein is ingested. resistance exercise; protein metabolism; nutrition; recovery

ABSTRACT. In the present experiment, the authors sought to differentiate between a distance and a grouping explanation for the symmetric versus asymmetric patterns of distractor interference in selective reaching. Participants [...]

Students participated in 3 experiments investigating the use of environment- and action-centered reference frames in selective reaching. They pointed to a green target appearing either with or without a red distractor. Target-distractor distance was manipulated, and distractor interference (difference between distractor trials and no-distractor trials) was measured in reaction time, movement time, and movement endpoint. Target-distractor distance determined the dominant frame of reference. Small distances evoked an environment-centered framework that encoded targets within an external context. Large distances evoked an action-centered framework that encoded targets relative to the start position of the hand. Results support the hypothesis that the brain represents spatial information in multiple frames of reference, with the dominant frame of reference being dependent on the task demands.

The article presents the current performance capacity in 11-15 year old Dutch adolescents who participated in an incremental cycle test (n = 509) and or in a shuttle run test (N = 1,198). Cycle test results increased significantly with age in both genders, also after normalization to body weight. Shuttle run test results increased significantly with age only in boys. Compared with previous data, the absolute performance capacity in the cycle tests was comparable to data from 15 years ago, whereas the performance capacity normalized to kg body weight and the shuttle run test results seem to be fairly lower compared with the former data. [ABSTRACT FROM AUTHOR]

A transversal study of isokinetic dynamometry of healthy shoulders is conducted to determine concentric shoulder external-internal rotator strength, dominant and non-dominant shoulder differences and agonist/antagonist ratios. Data presented are important for interpreting isokinetic shoulder rotator strength tests in elite volleyball players and could be relevant in rehabilitation and prevention of shoulder injuries.

Examines the plasma glucose and insulin response in trained athletes after consumption of sport feedings. Study of eight male subjects who consumed four commercially available sport feedings two hours before and one hour after a training session; Effect of sport feeding on postexercise glucose and insulin responses.