We analyzed the relation between subjective fatigue by hard exercise and stress hormone and cytokine data. The subjects are eight healthy men who had exercise experience. In this experiment, hard exercise was carried out in the first place. After two-hour rest, a performance test was carried out. The blood test was conducted 4 times (before exercise, after exercise, rest, and a performance test). Subjective fatigue was indicated using visual analogue scale (VAS). After the hard exercise and performance test, VAS increased and showed the significant difference. Lactic acid, adrenaline, noradrenaline, growth hormone, IL-6, and IL-8 increased after each exercise and showed the significant difference. Subjective fatigue and the value of lactic acid, and IL-6 showed significant positive correlations. These results suggest that lactic acid, and IL-6 may become an index of fatigue in this exertion model.

OBJECTIVES: Sarcopenia, decreased muscle volume and muscle weakness in the elderly is a serious risk of various adverse outcomes. Current diagnostic procedure for sarcopenia includes gait speed, grip strength, and percentage of skeletal muscle volume. However, lower leg muscle strength decreases much faster than grasp power, and we have evaluated the usefulness of its measurement using a recently developed instrument (Locomoscan). METHODS: Forty-three institutionalized elderly subjects were evaluated for their anthropometrical parameters, body composition, grasp and lower leg muscle strength, and gait speed. They were categorized into 2 groups; gait speed equal to or higher than 0.8 m/s and that below 0.8 m/s. RESULTS: Leg muscle strength per body weight was significantly greater in those with their gait speed equal to or higher than 0.8 m/s, whereas there was no significant difference in other parameters. Receiver operator characteristics analysis has shown that leg muscle alone significantly predicted the greater gait speed. CONCLUSIONS: Lower leg muscle strength can be useful for predicting gait speed.
Aged* ; Body Composition ; Body Weight ; Gait* ; Hand Strength* ; Humans ; Leg* ; Muscle Strength* ; Muscle Weakness ; Muscle, Skeletal ; Sarcopenia