The Effect of High-salt Diet Intake on Muscular Exercise Ability in Young Japanese Women.

Abstract

Abstract. This study was designed to test whether highsalt diet intake has some acute impaired effect to the muscular exercise ability due to the calcium deficit in muscle cell via the accelerated sodium-calcium exchanger. Six healthy young Japanese women (aged: 22.3 ± 1.9 yr) performed two types of muscle strength tests and ramp mode cycle ergometer exercise until exhaustion after normal-(NaCl is approximately 5.6 g) and highsalt (21.0 g) controlled diet intake on two separate days in random order. The urinary sodium excretion sampled during 12 hours on the high-salt diet day was significantly higher compared to that of normal-salt diet day (3301 ± 992 vs 1595 ± 540 mg; P<0.05), while there was no substantial difference between the urinary calcium excretion in high-and normal-salt diet days (58.6 ± 19.7 vs 55.0 ± 17.2 mg; ns). There were no significant differences in back strength, repeated maximal hand grip exercise . ability, and VO2max and duration time during ramp exercise between high-and normal-salt diet conditions. It was concluded that high-salt diet intake even exceeding 20 g per day had substantially no acute effect on muscular exercise ability in young Japanese women.