2.11. Endurance Training Protocol
The exercise regimen consisted of 20 min at 55% of maximum heart rate on a fixed-speed bicycle ergometer (11900 Community Rd, Poway, CA, USA) in the first week, which progressed to 30 min at 70% of maximal heart rate in the final week of the intervention. A polar heart rate monitor was used to measure the intensity of the workout (Polar S810, Polar Electro, Kempele, Finland).