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The effects of a university health-promotion course were evaluated before and after major course revision. Knowledges, attitudes, and behaviors were assessed at the beginning and end of the class for all students taking the original course during 1987–88 (n=195) and the revised course during 1988–89 (n=250). The content areas addressed were exercise, nutrition, substance abuse, stress management, safety, cancer, and cardiovascular disease (CVD). Course revisions involved altering content emphases, adding a series of quizzes, expanding the assigned readings, incorporating nutrition and substance abuse self-evaluations, and providing detailed lecture outlines for students and instructors. Within-group analyses showed that both courses produced significant (P

The purpose of this study was to investigate the effects of exercise intensity on the body composition of obese subjects during severe caloric restriction. Forty obese subjects (33 women, 7 men; 41 +/- 7.7 years; 106 +/- 26kg; body fat > 25% men, > 30% women) on a commercially prepared OPTIFAST 420kcal/day supplemented fast were randomized into groups that exercised at target heart rates corresponding to 40% and 60% of the heart rate reserve (HRR) at the start of the program. Training volume was similar for both groups at approximately 300kcal per session three times per week for 12 weeks. Body weight, body fat, and lean weight were similar for both exercise intensity groups at week one. Overall, body weight decreased by 15.3 +/- 6.7 kg (p < or = .05), and body fat decreased by 14.9 +/- 5.0 kg (p < or = .05) for the 40 subjects, whereas lean weight remained unchanged. No significant differences in body weight, body fat, or lean weight were observed between the two groups. The results of the current study indicated that while on a supplemented 420-kcal/day fast, exercise at 40% and 60% of the HRR affected body composition similarly when total training volume was held constant at 900kcal/week. Lean weight remained unchanged and accompanied a 14.9 +/- 5.0-kg decrease in body fat, which may have resulted when the volume of exercise (ie, 900kcals/wk) was factored into the exercise prescriptions. These results suggest that exercising at 60% of the HRR offers no advantages for body composition changes over those obtained from exercising at 40% of HRR when the total volume of exercise training is controlled.

Weanling S5B/P1 female rats were divided into four groups as follows: high fat diet, exercised (FE); high fat diet, unexercised (FU); high carbohydrate diet, exercised (CE); and high carbohydrate diet, unexercised (CU). After 25 days of progressive training, exercised rats ran on a motor-driven treadmill for 30 days at 25 m/min per 1 h at 0 degree grade for 6 days a week. Rats were weighed weekly throughout the experiment and food intakes were recorded for the last 3 weeks of the experiment. After euthanasia at 15 weeks of age, three muscles, liver, heart, kidney, 3 fat depots, and tibia-fibula were dissected out and weighted. The carcass, including weighted organs and fat depots, was analyzed for body fat. Exercised rats, regardless of diet, weighed slightly but significantly more than unexercised rats. They also tended to eat more food and to have a higher quantity of fat-free body mass than unexercised rats. Percent body fat was similar for exercised and unexercised rats. The tibia weighed significantly more (p less than 0.05) in CU than in FU rats but the weight was similar in CE and FE rats. The density of the tibia was significantly higher (p less than 0.01) in exercised than in unexercised rats.

Summary The purpose of this study was to determine the effects of various programs of physical activity on anxiety-related myocardial damage in rats. The anxiety-producing stress consisted of randomly distributed applications of a disturbing but nonpainful electrical shock. Physical activity consisted of long-duration, low-speed running. Three hundred and seventyfive male albino rats were randomly assigned to five comparison groups. The results show that the anxiety treatment produced marked myocardial damage. Animals preconditioned by eight weeks of exercise prior to the introduction of the anxiety treatment did not suffer as much myocardial damage as did animals that were not preconditioned. However, a group in which exercise and anxiety were introduced simultaneously had the highest incidence of myocardial necrosis. We conclude that aerobic exercise can modify the effects of a subsequent or simultaneous anxiety-producing stressful situation on the myocardium of the laboratory rat. The time at which the exercise is imposed determined the nature of the effect.

6 university team distance runners were randomly placed into experimental and control groups to determine the effect of progressive overloading with weights upon selected training responses. Both groups received identical training for 8 wk. with the exception that three days each week the experimental Ss wore weighted wristlets, anklets, and belts. Pre- and posttest energy metabolism measures were taken during and following both a low-intensity 15-min. run (9.7 km/hr, 0% grade) and a high-intensity run to exhaustion (16.1 km/hr, 9% grade). The energy metabolism responses to endurance training were significantly reversed by the progressive overloading with weights. The energy cost of the low-intensity run was increased and an unexpected shift toward greater anaerobic metabolism was observed.

One-hundred-fifty female rats were used in this study of the immediate and residual effects of prepubertal exercise upon organ and body weights. Animals were randomly assigned to 3 initial treatment groups: sedentary (S), voluntary (V), and voluntary plus forced exercise (V+F). Forced exercise consisted of 35 daily 30-min. swims with a tail weight of 2% of body weight. Two treatment periods were given, one just before puberty and another after 165 days of intervening voluntary activity. Sacrifices occurred posttreatment I, pretreatment II, and posttreatment II. Both (V) and (V+F) animals had lower body and absolute spleen weights but higher relative adrenal, heart, and liver weights than the controls. The absolute spleen and relative adrenal differences remained pretreatment II. Posttreatment II, lower body and absolute spleen weights were noted in (V) than in (S) groups. Although several significant interactions between treatments I and II were observed, only the lower body weight of active anim...

The observed differences in the soma and nuclear diameters reflect chronic changes specific to each exercise regimen used.

Previous studies have shown that hard physical training first lowers, then gradually raises the total amount of hemoglobin. Variable results have been reported on the white blood cell count and the total plasma protein. This study was undertaken in an attempt to obtain progressive data on human subjects throughout an entire season of training for sports. Three graduate students served as subjects. One underwent an extremely hard athletic training program. The second participated in a program of moderate intensity. The third subject served as a constant control. No marked hematological changes related to the training program were observed in the subject undergoing a moderate athletic training program. In the subject who underwent a hard athletic training program, the hemoglobin percentage showed an initial drop followed by a subsequent rise. A similar trend was observed in the hemoglobin per erythrocyte values. A slightly higher number of leucocytes was noted at the end of the training period. These changes are interpreted as caused by the physical training. The differential white count and the total plasma protein showed no appreciable changes directly attributable to the training involved.

Twenty-four postpubertal male albino rats were assigned randomly to sedentary-control (C), endurance-running (ER), and weight-lifting (WL) groups to study the effects of different chronic-exercise regimens on precapillary vascularity in the heart. The exercise routines were administered 5 d/wk. At the end of either 8 or 16 wk of treatments, half of the animals in each group were anesthetized. A 12% vinyl acetate solution was injected into the coronary arteries of each anesthetized animal at a pressure of 300-350 mmHg, through the ascending aorta. The injected hearts were removed and weighed. A 10% potassium hydroxide solution was used to digest tissues from the vinyl cast of each coronary arterial tree. No differences in absolute or relative heart weights were observed between the control and trained groups. When compared to the control group, the ER animals had heavier left and total coronary cast weights and higher total cast weight-to-heart weight ratios (P less than 0.05). Although an overall increase in precapillary vascularity of the heart was evident in the endurance-trained ER animals, none was found in the strength-trained WL group. However, the WL animals had significantly increased right coronary cast weights, and their ratios of right coronary cast weight to total cast weight also were higher than those of the control animals (P less than 0.05).