Relationships between heart rate target determined in different exercise testing in COPD patients to prescribed with individualized exercise training

Abstract

Background

It has been scientifically proven that pulmonary rehabilitation improves exercise tolerance and facilitates the carrying out of daily physical activities. To optimize the physical and physiological benefits, it is necessary to individualize the training intensity for each patient. The aim of this study is to compare the heart rate (HR) responses to three exercise modalities measuring aerobic fitness in chronic obstructive pulmonary disease patients, in order to easily prescribe individual target HRs for endurance training.

Patients and method

Fifty COPD patients (mean age: 60.1±8.5 years) were included in the study. Each patient carried out a cardiopulmonary exercise test, a 6-minute walk test (6MWT) and a 6-minute stepper test (6MST). During these tests, HR was recorded continuously. After the cardiopulmonary exercise test, the HR was noted at the ventilatory threshold (VT) and at the end of the two exercise field tests (6MWT _peak and 6MST _peak). The values of the HR during the last 3 minutes of both field tests were averaged (6MWT ₄₅₆ and 6MST ₄₅₆). Finally, the HR at 60% of the HR reserve was calculated with the values of the HR measured during 6MWT and 6MST (HRr _60%walk, HRr _60%step).

Results

The HRs measured during the 6MST were significantly higher than those measured during the 6MWT. The HRr _60%step was not significantly different from 6MWT ₄₅₆ and 6MWT _peak HR ( P=0.51; P=0.48). A significant correlation was observed between 6MWT ₄₅₆ and 6MWT _peak ( r=0.58). The 6MWT ₄₅₆ and 6MWT _peak HR were correlated with HRr _60%step ( r=0.68 and r=0.62). The VT could be determined in 28 patients. The HR _VT was not different from 6MWT ₄₅₆, 6MWT _peak, and HRr _60%step ( P=0.57, P=0.41 and P=0.88) and was correlated to 6MWT ₄₅₆, 6MWT _peak, and HRr _60%step ( r=0.45, r=0.40, r=0.48).

Conclusion

An individualized target HR for endurance training can be prescribed from the HR measured during routine tests, such as 6MWT or 6MST.