Rationale:

Current literature suggests healthy or low-BMI individuals experience the greatest increases in exercise minutes relative to high-BMI patients.

Objective:

In this report, we test the hypothesis that low-BMI cardiac rehabilitation patients experience greater gains in exercise capacity compared to high-BMI patients.

Methods:

We retrospectively reviewed all patients completing our phase-II cardiac rehabilitation program from 2001 through March 2005. 429 of 556 patients were available for analysis (360 men, 69 women). BMI status was stratified in <=25 or >25. Linear regression was used to model changes in minutes of exercise from baseline to 3-months by BMI status. Models were also stratified by gender.

Results:

Average age was 62.3 years. Average minutes of exercise per week changed from 82.5 to 147.8, a 66.5 minute increase (P <.001). Increased BMI led directly to increased exercise minutes (F = 7.0, P <.009). Patients with increased BMI experienced a 98% increase in exercise minutes from baseline to 3-mth compares to only a 50% increase for low BMI patients (P <.05). When stratified by gender, increased BMI led directly to increased minutes of exercise among both male (F = 165.1, P <.001) and female (F = 38.0, P <.001) patients.

Conclusion:

Patients with a BMI >25 experienced a 98% increase in exercise capacity vs. BMI <= 25 (50%, P <.05). Following 12 weeks of cardiac rehab, both groups were able to exercise at the same capacity. The implications for those with BMI >25 will further support the data on secondary improvement in cardiac risk status resulting in better lipid profiles, improved resting blood pressures, improvements in diabetic status and quality of life issues irregardless of weight loss.