Effects of acute cycling with electrical muscle stimulation of lower limbs on arterial stiffness / 体力科学

Endurance exercises, such as cycling or running, are useful for reducing arterial stiffness. However, individuals with a low physical fitness level, or patients suffering from leg diseases with pain, are unable to perform such moderate-intensity lower-limb exercises for long periods of time. The aim of this study was to evaluate the effects of acute cycling with Electrical muscle stimulation (EMS) on the brachial to ankle pulse wave velocity (ba-PWV). Ten healthy adult men performed 3 sessions, as follows of 20 min: cycling at 50% VO2max (C), cycling at an intensity of 50%VO2max subtracted from VO2 during EMS (LC), and cycling at the intensity of the LC trial while also being combined with EMS (LC+E). The ba-PWV was measured before and after each exercise. In addition, the femoral artery blood flow (BF) was measured in eight healthy adult men before and after exercise using an ultrasound imaging system. In the C and LC+E trials, the ba-PWV significantly decreased immediately after the exercise session, whereas the ba-PWV did not significantly change following the LC trial in any session. Compared with the baseline, the femoral artery BF values significantly increased after all trials. In the C and LC+E trials, the femoral artery BF was significantly greater than that in the LC trial. Acute endurance low-intensity cycling with EMS results in a reduction in the arterial stiffness which is similar to that with moderate-intensity exercise.

The change in salivary taurine level following 3 consecutive soccer match in collegiate male soccer players / 体力科学

Strenuous and consecutive exercise results in fatigue symptoms accompanied decrease in salivary secretory immunoglobulin A (sIgA) in athletes. On the other hand, it has been reported that plasma taurine concentration was increased after the high intensity exercise. However, change in salivary taurine concentration after strenuous and consecutive exercise is unknown. The purpose of this study was to investigate the relationship between fatigue symptoms and changes in salivary taurine concentration in collegiate male soccer players. Thirty seven collegiate male soccer players participated in three consecutive days of match program. To detect of fatigued players, we measured awakening heart rate and body weight. As the results of these two measurements, we divided subjects to two groups (non-fatigue group, n=15; fatigue group, n=22). We also measured salivary sIgA and taurine concentrations before and after program. Before the program, there were no significant differences in any parameters between two groups. Salivary flow rate and sIgA secretion rate were significantly decreased after the program in the fatigue group. Furthermore, salivary taurine concentration was significantly increased after the program in the fatigue group. In the non-fatigue group, there were no significant differences in any parameters during program. Our results indicated that salivary taurine concentration increased after consecutive high-intense exercise in the collegiate male soccer players.