Training level comparison study. Effect of high and low intensity exercise on ventilatory threshold in men with
B E Jensen1, B J Fletcher, J C Rupp
1Emory University, Atlanta, Georgia, USA.
Purpose:
To determine whether exercise at low intensity (LO; 50% of peak VO2) or high intensity (HI; 85% of peak VO2) results in improvement of the ventilatory threshold (VT), 186 men with coronary artery disease (CAD) were enrolled in an exercise study for 1 year.
Methods:
A symptom-limited exercise test was performed at baseline and the heart rate corresponding to 50% and 85% of peak VO2 was determined. Subjects were randomized to LO or HI intensity exercise. Exercise sessions included 45 minutes of walking/jogging and/or stationary cycling at the appropriate target heart rate and were conducted 3 days per week. The exercise test was repeated at 3 and 6 months. Target heart rates were revised to adjust for training.
Results:
Both LO and HI resulted in improved VO2 at VT and peak. However, HI resulted in greater improvement than LO.
Conclusion:
Among this population, both HI and LO improve the VO2 at VT and peak, but the improvement is greater with HI. The VT can be a useful adjunct to heart rate and peak oxygen uptake when prescribing exercise.
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