Skin cold stimulation combined with low-load cycling training improves oxygen uptake and muscle strength in sedentary healthy adults

Abstract

  Concurrent improvements in aerobic capacity and muscle strength in response to aerobic training with skin cold stimulation (SCS) have not yet been reported. This study examined whether aerobic training with SCS has an effect on oxygen uptake and muscle strength in sedentary healthy adults. The 2 groups of 20 participants were constant ergometer cycling training with SCS (SCS group, n = 11) and without SCS (CG group, n = 9). Training intensity was 80% of oxygen uptake at the ventilation threshold (VO_2VT); duration was 30 min/day, 3 days/week, for 6 weeks. Significant improvements in maximum oxygen uptake (VO_{2 max}) (p = 0.006), VO_2VT (p = 0.003), and maximal power output (p = 0.005) were observed in the SCS group, whereas the CG group had statistically increased maximal power output (p = 0.007), but not VO_{2 max} and VO_2VT. The VO_2VT change ratio was significantly greater for the SCS versus CG group (p = 0.007). Maximum voluntary contraction (MVC) of leg extension muscle strength increased in the SCS group (p = 0.037), but not in the CG group. Muscle mass of the leg after training also increased in the SCS group (p = 0.012) compared with no muscle mass changes in the CG group. These results suggest that low-intensity, short-duration, cycling exercise training with SCS improves both aerobic capacity and muscle strength concurrently in sedentary adults.