Aerobic Exercise Intensity in Breast Cancer Patients: A Preliminary Investigation

Abstract

This study compared the heart rate (HR), rate of perceived exertion (RPE), and blood lactate (BL) responses to aerobic exercise between posttreated breast cancer patients and apparently healthy, age-matched controls. Seven patients and 7 control subjects underwent a submaximal treadmill test for the estimation of Vo(2max). Exercise intensities of 40%, 60%, and 70% of Vo(2max) were calculated from the treadmill test and randomly examined between groups during three 9-minute exercise bouts on 3 different days. Independent samples t tests were used to examine the HR, RPE, and BL responses at each intensity between groups. No significant differences were observed between the control and patient groups for HR, RPE, and BL at 40% (101 +/- 9 vs 101 +/- 11 bpm, P = .979; 8 +/- 1 vs 9 +/- 3, P = .237; and 1.11 +/- 0.73 vs 1.26 +/- 0.64 mmol/L, P = .188, respectively) and 60% (127 +/- 17 vs 117 +/- 13 bpm, P = .523; 12 +/- 2 vs 11 +/- 3, P = .267, and 3.83 +/- 2.48 vs 2.23 +/- 1.65 mmol/L, P = .237, respectively) of Vo(2max) . At 70% of Vo(2max), no significant differences were found for HR (151 +/- 27 vs 135 +/- 13 bpm, P = .704) and RPE (14 +/- 1 vs 13 +/- 3, P = .181), but lower BL responses were observed in the patient group (7.70 +/- 1.62 vs 3.29 +/- 1.08 mmol/L, P < .0005). The results suggest similar HR, RPE, and BL responses between patients and control subjects at 40%, 60%, and 70% of Vo(2max) , except for BL at 70% of Vo(2max). The lower BL response in the patient group at 70% of Vo(2max) was somewhat unexpected. Further research is needed to confirm or refute the results of this study to allow for a clearer understanding of the physiological responses of breast cancer patients to aerobic exercise at moderate or higher intensities so that safer aerobic exercise prescriptions can be developed for this population.