EVALUATION OF EXERCISE PRESCRIPTION BASED ON THE HEART RATE AND WORK RATE AT THE LACTATE THERSHOLD IN OBESE SUBJECTS WITH AND WITHOUT HYPERTENSION

Prescribed exercise regimens based on the target heart rate (THR) and the target work rate (TWR) on a cycle ergometer at the intensity of the lactate threshold (LT) were evaluated before, and after 6 and 12 weeks of exercise therapy in obese subjects with (OBHT, n=38) and without hypertension (OB, n=55) matching for age, sex, BMI, body composition, as well as the blood glucose, cholesterol and triglyceride level. THR was 97.8±9.2 in OBHT and 98.3±10.7 in OB without group differences. The resting HR was higher in OBHT than in OB (76.3 vs. 72.1). Both the relative THR (%HR reserve) and the relative TWR (%Body weight) were lower in OBHT than in OB. During the training period, the VO2max, THR and TWR increased while body fat decreased significantly in both groups. The resting BP and HR decreased, and the %HRR increased significantly in OBHT. In conclusion, the lower THR and TWR are therefore recommended when initially prescribing an exercise regimen without an exercise stress test for obese individuals, particularly for the obese subjects with HT based on the exercise intensity at LT. Thereafter, careful modifications in the prescribed exercise regimen will be needed according to improvements in the fitness level and in coronary risk factors.