NR Supplementation and Exercise

Participants in the NR supplementation + exercise group will undergo oral NR supplementation for 40 days. NiagenTM is the name for the dietary supplement containing NR (ChromaDex, Inc. Irvine, USA). The total dosage of NR per day will be 1000mg. This supplementation time of 40 days 1000mg/day

During days 17-38 of the NR/placebo intake, participants will perform a 3-weeks supervised exercise training program with four \~30 min exercise sessions per week (two endurance session on a bike at 70%Wmax and two high intensity interval (HIIT) sessions.