A comparison between computer-controlled and set work rate exercise based on target heart rate

Good exercise prescriptions provide work rates (WRs) that maintain heart rates (HR) in a target zone and at a percent of maximum metabolic equivalent (%METmax). HR and MET were evaluated from computer-controlled and set WR (constant speed) sessions (20 min at 65% METmax). Computer-controlled WR used a control algorithm to adjust speed and grade to maintain the target HR. The set WR (mean +/- S.D.) HR (139 +/- 8 bpm) was lower (p less than 0.05) than the target (147 +/- 3 bpm) and computer-controlled HRs (153 +/- 5 bpm). The set WR MET (8.6 +/- 2.2) was not different than the target (8.6 +/- 2.2), but both were lower than computer-controlled exercise (9.7 +/- 2.2). Computer-control time in target HR zone (16 +/- 5 min) was significantly (p less than 0.004) greater than set WR exercise (6 +/- 5 min). Computer-controlled WR was significantly better in maintaining target HR and the MET values were not physiologically different than target WRs.