Sweat is a hypotonic fluid excreted by sweat glands to cool the body. There are conflicting reports on whether or not body composition has an effect on thermoregulatory responses especially during exercise. This study...Sweat is a hypotonic fluid excreted by sweat glands to cool the body. There are conflicting reports on whether or not body composition has an effect on thermoregulatory responses especially during exercise. This study was aimed at determining and comparing sweat rate and electrolyte composition in underweight (BMI BMI 30 kg/m<sup>2</sup>) during moderate exercise. Forty women (19 - 25 years) were used during this study after assessing their health status. They were stratified for BMI with each group having a total of ten women. It was ensured that all the women used in the study were euhydrated before commencing the research. Before sweat collection, the treadmill was calibrated according to the Bruce Treadmill Protocol. Sweat samples were obtained with a sweat suction apparatus from a 120 cm<sup>2</sup> circular area marked on the skin of the face and neck, after a 15 minute fast walk on a treadmill at an inclination of 15° and at a speed of 4.2 km/h at 27°C room temperature. The time at which sweating commenced in the subjects was recorded. Sweat rate (L/hour) was calculated using the formula: sweat rate (L/hr) = (pre-exercise body weight - Post-exercise body weight)/exercise duration. Each sweat sample was collected and analysed immediately. The results showed that obese women had a significantly (P < 0.05) higher sweat rate and underweight women had a significantly (P < 0.05) lower sweat rate than all the other groups. Furthermore, subjects with a high body surface area showed significantly higher sweat rates compared to subjects with lower body surface area. Sweat electrolyte composition did not change in all BMI groups. In conclusion, obese subjects are more likely to develop fluid imbalances than underweight and normal weight subjects during moderate exercise. Also, underweight women might be at a thermoregulatory disadvantage because of their reduced body fat and body surface area.展开更多
To study the effects of a chocolate bar supplementation before exercise on improving recovery of physiological and metabolic changes induced by exercise, 16 male students aged 18-20 years voluntarily served as subject...To study the effects of a chocolate bar supplementation before exercise on improving recovery of physiological and metabolic changes induced by exercise, 16 male students aged 18-20 years voluntarily served as subjects. A crossover design was employed. Each subject took part in two trials and ran an hour on a treadmill with the intensity of keeping heart rate at 148-150 min for each trial. Results showed that plasma glucose levels of subjects increased significantly (5.42±0.83 mmol/L) at 15 min after ingestion of a chocolate bar and maintained in moderate high levels (4.92 ±0.57 mmol/L) until 30 min after an hour's running while the glucose levels were low and dropped to under normal ranges (3.84 ± 0.31 mmol/L) at 30 min after exercise as they were with a supplement of placebo. Results of plasma FFA, blood lactate and plasma urea nitrogen levels and RPE all indicated that chocolate bar supplementation before exercise benefits to create the necessary prerequisite for exercise and recovery展开更多
文摘Sweat is a hypotonic fluid excreted by sweat glands to cool the body. There are conflicting reports on whether or not body composition has an effect on thermoregulatory responses especially during exercise. This study was aimed at determining and comparing sweat rate and electrolyte composition in underweight (BMI BMI 30 kg/m<sup>2</sup>) during moderate exercise. Forty women (19 - 25 years) were used during this study after assessing their health status. They were stratified for BMI with each group having a total of ten women. It was ensured that all the women used in the study were euhydrated before commencing the research. Before sweat collection, the treadmill was calibrated according to the Bruce Treadmill Protocol. Sweat samples were obtained with a sweat suction apparatus from a 120 cm<sup>2</sup> circular area marked on the skin of the face and neck, after a 15 minute fast walk on a treadmill at an inclination of 15° and at a speed of 4.2 km/h at 27°C room temperature. The time at which sweating commenced in the subjects was recorded. Sweat rate (L/hour) was calculated using the formula: sweat rate (L/hr) = (pre-exercise body weight - Post-exercise body weight)/exercise duration. Each sweat sample was collected and analysed immediately. The results showed that obese women had a significantly (P < 0.05) higher sweat rate and underweight women had a significantly (P < 0.05) lower sweat rate than all the other groups. Furthermore, subjects with a high body surface area showed significantly higher sweat rates compared to subjects with lower body surface area. Sweat electrolyte composition did not change in all BMI groups. In conclusion, obese subjects are more likely to develop fluid imbalances than underweight and normal weight subjects during moderate exercise. Also, underweight women might be at a thermoregulatory disadvantage because of their reduced body fat and body surface area.
文摘To study the effects of a chocolate bar supplementation before exercise on improving recovery of physiological and metabolic changes induced by exercise, 16 male students aged 18-20 years voluntarily served as subjects. A crossover design was employed. Each subject took part in two trials and ran an hour on a treadmill with the intensity of keeping heart rate at 148-150 min for each trial. Results showed that plasma glucose levels of subjects increased significantly (5.42±0.83 mmol/L) at 15 min after ingestion of a chocolate bar and maintained in moderate high levels (4.92 ±0.57 mmol/L) until 30 min after an hour's running while the glucose levels were low and dropped to under normal ranges (3.84 ± 0.31 mmol/L) at 30 min after exercise as they were with a supplement of placebo. Results of plasma FFA, blood lactate and plasma urea nitrogen levels and RPE all indicated that chocolate bar supplementation before exercise benefits to create the necessary prerequisite for exercise and recovery
