ABSTRACT
In the present study, we examined cardiovascular response to static and dynamic hand-grip exercise at equivalent work load (peak tension) and tension-time index (TTI, integrated tension for time) in healthy young (n=8) and elderly (n=8) males. Static and dynamic exercises were conducted for 75 s and 150 s at 30% of maximal voluntary contraction (MVC) and for 45 s and 90 s at 50%MVC, respectively. Arterial pressure was continuously measured on a beat basis. Blood pressure at the end of exercise and the magnitude of pressor response induced by exercise did not differ significantly between static and dynamic exercises at the two work loads. The magnitude of pressor response tended to depend on work load. These findings were the same in both age groups. Consequently, it was indicated that blood pressure responses to static and dynamic hand-grip exercise at equivalent work load and TTI did not differ both in young and elderly people. Furthermore, it was suggested that central command and muscle metabolite induced stimulation of the exercise pressor reflex during static and dynamic exercise were similar based on the results of relative perceived exertion and blood pressure response during post-exercise arterial occlusion.
ABSTRACT
Eighty healthy males aged from 26 to 34 years were studied to evaluate the effects of regular physical training on body composition, respiratory functions, circulatory functions, blood constituents, and physical fitness. The physical training consisted of jogging, volleyball, handball, socker, judo, fencing, and others. The combination of these sports were assigned to all the subjects to be performed for 130 minutes every week-day from April, 1979 to January, 1980.<BR>1) The subjects had, on the average, 518 g of carbohydrate, 125 g of protein including 74 g of animal protein, and 85 g of fat summing up to 3300 kcal a day. These nutrients intake was 30% to 50% excess over the normal value for male Japanese of the corresponding age. Body weight, however, did not change and body fat decreased in spite of large excess food intake. Serum HDL-cholesterol increased and atherogenic index decreased. These facts lead to a conclusion that the noxious effects of overeating can be cancelled by physical activity.<BR>2) Pulse wave velocity of the aorta which reflects the elasticity of the aortic wall decreased. This means that changes in the physical property of the aorta due to aging process can be reversed through physical training. Decrease in pulse wave velocity dose not always mean the regression of atherosclerosis, but the additional findings such as decrease in body fat and in atherogenic index and increase in HDL-cholesterol support the possibility of regression of aterosclerosis by physical activity.<BR>3) The results of physical fitness test indicated marked improvement of physical abilities which reflect muscular strength, muscular power, muscular endurance, body flexibility, agility, anaerobic power, and aerobic power.