This study evaluated the relationships of exercise habits and parents' body type to the body type and composition in females aged 15-20 years, and compared the results with those in boys in our previous study. The subjects (n=249) were divided into exercise (n=124) and non-exercise (n=125) groups. We measured the height, body weight, body mass index (BMI), percent body fat, and skinfold thickness, and surveyed their parents' body type at 20 years of age. Regular exercise significantly decreased the percent body fat, but did not influence BMI. The subjects' body type and body composition reflected both their father's and mother's body type. However, regular exercise negates hereditary predisposition as reported for the boys.

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Visual stimulation-reaction time and subsequent strike time in the sport of kendo were assessed using electromyographic (EMG) reaction time. Fourteen male college students (kendo athletes (n=7), non-kendo athletes (n=7)) were asked to perform a kendo strikes in response to visual stimulation from a flashing light signal. The strikes employed, the Hiki-Men (HM) and Hiki-Kote (HK), were performed using a bamboo sword, or Shinai, using both of the upper limbs as quickly as possible. The EMG signals from the right (R) and left (L) biceps brachii, the R-, and L-triceps brachii, and R-flexor carpi ulnaris muscles were recorded simultaneously together with the elbow joint angle and hitting shock signals. Total task time (TTT), pre-motor time (PMT), motor time (MT), and action time (AT) were measured for the HM and HK tasks. The photo stimulation body reaction time (BRT) was also measured. Significant strong positive correlations were observed between PMT and TTT for both HM and HK tasks (p<0.01, r=0.93-0.94). Multiple regression analysis was used to determine the contribution of each component of the model in TTT. The standardized partial regression coefficient (β) was significant (P<0.01) for MT (β=0.36-0.38), AT (β=0.49-0.56) and was highest for PMT (β=0.79-0.80). The individual time ratio for PMT, MT and AT to TTT was approximately 50%, 20% and 30%, respectively. No significant correlations were observed between BRT and TTT for the HM and HK tasks (r=-0.02, 0.16). These results suggest that PMT is the most important component contributing to the TTT, and that BRT is not correlated to the TTT in kendo strikes.

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To evaluate the effects of mattress size on sleep feelings estimated by standardized OSA sleep inventory MA version and sleep quality measured by actigraph, eighteen healthy subjects (8 males, 10 females), aged 61-65, were recorded, sleeping in their homes for 15 consecutive nights under two crossover designed conditions from Friday. A subject slept for 7 consecutive nights (4 adaptation nights and 3 nights for analysis) on a 78cm wide mattress first and then for 8 consecutive nights (4 adaptation nights, 3 nights for analysis and excluded last night) on a 100cm wide mattress. The results showed the sleep on a 100cm mattress indicated better sleep quality and feelings.

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The purpose of the present study was to examine the relationship between blood lactate (La) and blood osmolarity (Osm) during high intensity constant load exercise in heat. Seven male subjects (age; 20.7±1.4yrs, height; 174.1±4.9cm, body mass; 68.1±4.3kg, VO_2max; 47.3±5.8 ml・kg^<-1>・min^<-1>) performed a 80%VO_2max exercise for 10 min by using cycle ergometer on two different conditions : an ambient temperature of 20℃ and 50% relative humidity (control; CON) and 40℃ and 50% relative humidity (heat trial; HT). Trials were conducted within a week in random order. Forearm skin blood flow during exercise were higher in HT compared with CON (P<0.05), however, no difference in oxygen consumption during exercise was observed between HT and CON. These results suggest that blood flow to active muscles during exercise may be unchanged by HT. In spite of the similar oxygen consumption, exercise in HT resulted in a higher La at 3 min during exercise compared with CON (6.0±0.3mmol・1^<-1> vs 5.0±0.6mmol・1^<-1>, P<0.05). In contrast, Osm was unchanged in HT during exercise and recovery compared with CON. In addition, the changes in Osm were highly correlated with the changes in total blood electrolytes (Na^+, K^+ and Cl^-) including La^- (r=0.98, P<0.05). It is suggested from these results that the changes in Osm during exercise in HT and CON may be controlled by the change in total blood electrolytes but not only the change in La^-. The reason for elevated La in HT at earlier time during exercise was unknown.

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It is reported that walking is effective for most of elderly people to maintain their physical fitness. The walking, especially the free speed walking can be continued safely and comfortably. However, it is not well investigated that the free speed walking is whether sufficient exercise to maintain their physical fitness. In this paper, the movement intensity of the free speed walking was evaluated with physiological indices. Ten healthy women (aged 75〜80) as the elderly group and Ten young men (aged 22〜28) as the control group were selected as subjects. The oxygen intake level (V0_2) and the heart rate (HR) were measured under the free speed walking and the rest conditions. In the rest condition, V0_2 of the elderly group was 3.06ml/kg/min and that of the control group was 4.93ml/kg/min. These values are different from American College of Sports Medicine (ACSM)'s recommended value (3.5ml/kg/min) that is widely used for evaluating the metabolic equivalents (METs). It can be said that the effect of aging has to be considered for estimating METs. The movement intensity of the free speed walking was measured as 3.84METs, which is classified as middle-class activity strength. It was suggested that the free speed walking is an appropriate activity for elderly people to improve their QOL.

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