Experimental: High-intensity interval training

Intensity will be determined using a combination of heart rate reserve (HRR, calculated as HRR= \[max HR - resting HR\] x \[% training\] + \[resting HR\]) and ratings of perceived exertion (RPE). The protocol will involve 10 60-second intervals of high intensity interspersed with 9 60-second low-intensity intervals. The initial high intensity intervals will start at 80% of the HRR (RPE=14-17) and progress by 10% every 4 weeks. Low intensity intervals will be performed at 30% of HRR (RPE=9-11). Three-minute warm-up and 2-minute cool-down periods will be performed at 30% of HRR. Total HIIT time including warm-up and cool-down is 24 minutes.

Experimental: Moderate-intensity continuous training

Intensity will be determined using a combination of heart rate reserve (HRR, calculated as HRR= \[max HR - resting HR\] x \[% training\] + \[resting HR\]) and ratings of perceived exertion (RPE). The MICT protocol will be increased using a progression schedule previously used (initial intensity at 40% HRR (RPE=9-11), and progressed by 10% HRR every 4 weeks up to 60% HRR (RPE=13-14) will be maintained until the end of the intervention). A 3-minute warm-up and 2-minute cool-down will be performed at 30% HRR (RPE=9-11). The total duration of MICT, including warm-up and cool-down, will be 35 minutes.