ABSTRACT
The purpose of this study was to examine the effect of active recovery between two strenuous anaerobic exercises separated by a short time interval. Eight healthy adult male volunteers (age: 24.8±1.8 yrs, height: 170.6±2.5 cm, weight : 70.1 ±2.5 kg) underwent five exercise sessions. Each session consisted of a warm-up, the first anaerobic exercise test (40 sec of exhaustive cycle ergometer exercise), a 30 min inactive (seated) or active recovery period, and a second anaerobic exercise test. During the active recovery period, subjects executed one of four different intensity pedaling tests (60, 80, 100, 120% of predetermined lactate threshold intensity) for 10 min. There were no significant differences in mean power and peak blood lactate concentration among sessions during the first anaerobic exercise test. Significant differences were found in the blood lactate concentration among sessions during the second anaerobic exercise test, and significant differences were found in mean power for the second anaerobic exercise. Optimal intensity related to the blood lactate removal rate was 83.3±7.1%LT, and that related to the working capacity recovery rate was 68.3±11.8%LT.<BR>From these results, concerning blood lactate removal rate, it was suggested that between 80%LT and 100%LT was an effective intensity. As for performance, the effective intensity was less than 100%LT.
ABSTRACT
The purpose of this study was to determine the change in elbow flexor isometric torque at different phases of the menstrual cycle in humans. The subjects were six eumenorrheic females (age 22.0±3.5yr ; height 156.5±3.3cm ; body mass 50.2±4.9 kg) . The serum luteinizing hormone (LH), estradiol and progesterone levels, maximal voluntary contraction (MVC), integrated electromyographic activity (iEMG), interpolated twitch torque, evoked contractile properties, anthropometric parameters and Profile of Mood States (POMS) were measured at three different phases of the menstrual cycle, i. e., the menstrual, ovulatory and luteal phases. The MVC was significantly higher in the ovulatory phase than in the menstrual and luteal phases (P<0.05) . The iEMG, calculated voluntary activation and anthropometric parameters did not change significantly over the menstrual cycle. The MVC/iEMG ratio (electromechanical efficiency) and the evoked peak torque were also significantly higher in the ovulatory phase than in the menstrual and luteal phases (P<0.05, P<0.01) . In the menstrual phase, the fatigue and anger subscale score of POMS were significantly higher (P<0.05) and the vigor subscale score was significantly lower than in the other phases (P<0.05) . These results indicate that the variation in MVC observed over the menstrual cycle may be related to the intrinsic contractile properties rather than neural or psychological factors.