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This study investigated the effect of varying exercise intensity on the thermic effect of food (TEF). Sixteen lean male subjects were matched for ${\text{VO}}_2\max$ and randomly assigned to either a high or low intensity group for 30 min of treadmill exercise. Caloric expenditure was measured using indirect calorimetry at rest and at 30-min intervals OYer 3 hrs following each of three conditions: a 750-kcal liquid meal, high or low intensity exercise, and a 750-kcal liquid meal followed by high or low intensity exercise. Low intensity exercise enhanced the TEF during recovery at 60 and 90 min while high intensity enhanced it only at 180 min but depressed it at 30 min. Total metabolic expense for a 3-hr postmeal period was not differently affected by the two exercise intensities. Exercise following a meal had a synergistic effect on metabolism; however, this effect was delayed until 180 min postmeal when exercise intensity was high. The circulatory demands of high intensity exercise may have initially blunted the TEF, but ultimately the TEF measured over the 3-hr period was at least equal to that experienced following low intensity exercise.

The purpose of this study was to examine the effects of postexercise feeding on plasma levels of insulin, testosterone, cortisol, and testosteronexortisol (T:C). Ten experienced, resistance trained males (20.7 ± 0.95 years) were given whole food (WF: protein 38 g; carbohydrate 70 g; fat 7 g), a supplemental drink (SD; isocaloric and isonitrogenous to WF), an isocaloric carbohydrate beverage (C), or a placebo beverage (P) immediately, 2 and 4 hours after a standardized weight training protocol on 4 days, each separated by 1 week, in a repeated measures design. Subjects also received a standardized meal at 7 and 12 hours postexercise. Insulin, testosterone, and cortisol were measured pre-exercise and during 24 hours of recovery (at 0.5,2.5,4.5,8, and 24 hours) using venous blood samples. Significant (condition × time) interactions were found for insulin, testosterone, and T:C, but not for cortisol (p < .05). The SD yielded a greater response for insulin than all other conditions. Conversely. P demonstrated the greatest values for testosterone and T:C at 2.5 and 4.5 hours postexercise. Cortisol did not vary between conditions and there were no condition effects for insulin, testosterone, cortisol, and T:C at 8 or 24 hours. In conclusion, the efficacy of postexercise feeding for optimizing T:C and muscle growth is unclear; however, consumption of SD appears to maximize circulating insulin for several hours following resistance exercise.

The effects of cognitive strategies on pain tolerance and performance in subjects with muscle soreness were investigated. Female (n = 18) and male (n =12) subjects were matched for strength and then randomly assigned to dissociation, association, or control groups. Muscle soreness was induced in the quadriceps and hamstrings muscle groups by repeated eccentric contractions against heavy resistance, which resulted in significant decrements in peak torque (PT) and total work (TW). ANOVAs revealed no significant group differences (p < .05) in muscle soreness, state anxiety, and estimated strength and endurance performance 48 hr following the soreness induction. Association strategy subjects increased their quadriceps strength performance following cognitive intervention, whereas strength performance in the dissociation and control groups was not affected. No significant treatment effects were observed for hamstrings strength or quadriceps and hamstrings endurance. Both dissociation and association groups perceived that using the strategies enhanced their performance. This illusory efficacy effect may have implications for performance enhancement, particularly in injury rehabilitation.

Bone mineral density (BMD) development and maintenance is enhanced with weight-bearing exercise, while bed rest and zero gravity results in BMD loss. The purpose of this study is to determine if BMD is significantly different in female athletes engaged in weight-bearing versus nonweight-bearing sports. Six BMD sites and anthropometric measurements were assessed at 3 equal intervals utilizing 2-way ANOVA’s. Controlling for body-weight, differences in BMD were investigated utilizing ANCOVA. Pearson and Spearman Rank Correlations were utilized to investigate interrelationships between anthropometric, VO₂max, and BMD measurements. Swimmers were taller and heavier with greater percent, body fat. BMD was significantly different between runners and swimmers only at the distal, which was higher for swimmers at 6 months. There was no difference in radial BMD when utilizing ANCOVA, with weight serving as the covariate. Swimming does not appear to be a contraindicated activity for BMD accrual and maintenance.