Background. The authors examined the importance of the frequency of aerobic exercise training in multidisciplinary rehabilitation in improving health-related quality of life in the short run in patients with documented coronary artery disease.
Methods. Patients (114 males and 16 females; age range, 32-70 years) were randomized into either a high-frequency or a low-frequency exercise training program (10 versus 2 sessions per week, respectively) as part of a 6-week multidisciplinary cardiac rehabilitation program. The General Health Questionnaire and the RAND-36 were used to assess changes in psychological distress and subjective health status.
Results. After 6 weeks, high-frequency patients reported significantly more positive, change in "psychological distress" (P < 0.05), "mental health" (P = 0.05), and "health change" (P < 0.01), than low-frequency patients. Apart from changes in mean scores, individual effect sizes indicated that a significantly greater percentage of high-frequency patients experienced substantial improvements in "psychological distress" (P < 0.01), "physical functioning" (P < 0.05), and "health change" (P < 0.05), compared with low-frequency patients. In addition, deterioration of quality of life was observed in a considerable number of high-frequency patients (ranging from 1.7% to 25.8% on the various measures).
Conclusions. The frequency of aerobic exercise has a positive, independent effect on psychological outcomes after cardiac rehabilitation. However, this benefit after high-frequency rehabilitation appears to be limited to a subgroup of patients. Further investigation is required to identify these patients. Results provide input into recent controversies regarding the role of exercise training in cardiac rehabilitation.
From the Departments of *Human Movement Sciences, †Northern Center for Healthcare Research, and ‡Psychology, University of Groningen, Groningen; the §Beatrixoord Cardiac Rehabilitation Center, Haren; the ∥Department of Cardiology/Thoraxcenter, University Hospital Groningen, Groningen, The Netherlands; and from ¶Emory Heartwise Risk Reduction and Prevention Program, Emory University, Atlanta, Georgia.
This study was supported by a research grant (92-354) from The Netherlands Heart Foundation, The Hague, The Netherlands.
Address for correspondence: Marike A. Berkhuysen, MSc, who is now at Emory Heartwise Risk Reduction Program, Emory University, 1525 Clifton Road NE, 5th Floor, Atlanta, GA 30322.