Low-intensity resistance exercise with slow lifting and lowering does not increase noradrenalin and cardiovascular responses.

The aim of this study was to investigate the effect of low-intensity resistance exercise with slow lifting and lowering (LSL) on plasma endothelin-1 (ET-1) and noradrenalin concentrations in young healthy adults. Eight healthy males participated in this study (age 19.0 +/- 0.5 years, mean +/- SD). The LSL performed the 10 repetitions with 3 s eccentric (lowering phase) and 3 s concentric (lifting phase) muscle actions. The high-intensity resistance exercise with normal lifting and lowering (HNL) performed the 10 repetitions with 1 s eccentric (lowering phase) and 1 s concentric (lifting phase) muscle actions. The load was set to 40% of one repetition maximal (1RM) for LSL and 80% of 1RM for HNL. Plasma ET-1 and noradrenalin concentrations were measured before and after each type of exercise. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP) and heart rate (HR) during LSL and HNL were measured. The rate-pressure product (RPP) was calculated from SBP and HR. There were no significant differences in the plasma ET-1 concentration between LSL and HNL. However, the plasma noradrenalin concentration was significantly increased after HNL, compared with LSL (P < 0.001). SBP, DBP, PP, MAP, HR and RPP during LSL were significantly lower compared with HNL (P < 0.05: PP and HR; P < 0.01: RPP; P < 0.001: SBP, DBP and MAP). These results suggested that LSL may suppress the increase in plasma noradrenalin concentrations and cardiovascular responses.