During prolonged, constant-workload exercise, percentage of heart rate reserve (%HRR) increased significantly more than oxygen consumption reserve (%VO2R) (P<0.001), especially in females.
Do %HRR and %VO2R maintain equivalency during prolonged exercise at a constant workload?
Heart rate reserve and VO2 reserve do not maintain equivalency during prolonged exercise due to cardiovascular drift, particularly in females, suggesting they should not be used interchangeably for exercise prescription.
valor p: p=<0.001
Abstract Background Percentages of heart rate reserve (%HRR) and oxygen consumption reserve (%VO 2 R) provide equivalent intensities during incremental exercise. These percentages increase during prolonged exercise at a constant workload, and it is unclear if they increase to a similar degree. In this study, we tested whether %HRR and %VO 2 R maintain equivalency during prolonged exercise at a constant workload. Methods Fifteen males and 12 females participated in an incremental cycle ergometer test to determine maximum VO 2 . They then performed 2 prolonged exercise trials, 1 for 30 min at a vigorous-intensity workload corresponding with 60% VO 2 R, and 1 for 60 min at a moderate-intensity workload of 40% VO 2 R. HR and VO 2 were measured continuously, and %HRR and %VO 2 R were reported every 5 min. A fan and consumption of cold water were used to minimize heat stress. Results Both %HRR and %VO 2 R increased during constant-workload exercise ( P < 0.001), and %HRR increased significantly more than %VO 2 R ( P < 0.001). Females exhibited greater %HRR than %VO 2 R beginning at 10 min into both trials ( P < 0.05), while %HRR exceeded %VO 2 R for males beginning at 15 min of the 30-min trial ( P < 0.05) and at 30 min of the 60-min trial ( P < 0.05). HRR values for females were significantly greater than those for males at most time points ( P < 0.05). Conclusion: During prolonged, constant-workload exercise, cardiovascular drift results in a greater increase in %HRR than %VO 2 R, and this is more pronounced in females than males.
Wynne et al. (Fri,) reported a other. Prolonged exercise at constant workload vs. Comparison between %HRR and %VO2R was evaluated on Equivalency of %HRR and %VO2R during prolonged exercise at a constant workload (p=<0.001). During prolonged, constant-workload exercise, percentage of heart rate reserve (%HRR) increased significantly more than oxygen consumption reserve (%VO2R) (P<0.001), especially in females.