Authors
Hambrecht R. Niebauer J. Marburger C. Grunze M. Kalberer B. Hauer K.
Schlierf G. Kubler W. Schuler G.
Institution
Department of Cardiology, Medizinische Universitatsklinik, Heidelberg,
Germany.
Title
Various intensities of leisure time physical activity in patients with
coronary artery disease: effects on cardiorespiratory
fitness and progression of coronary atherosclerotic lesions
[see comments].
Comments
Comment in: J Am Coll Cardiol 1993 Aug;22(2):478-9
Source
Journal of the American College of Cardiology. 22(2):468-77, 1993 Aug.
Abstract
OBJECTIVES. This study was designed to define the effect of different levels
of leisure time physical activity on cardiorespiratory
fitness and progression of coronary atherosclerotic lesions
in unselected patients with coronary artery disease. BACKGROUND. It has been
shown in various studies that regression of coronary atherosclerotic lesions
can be achieved by means of lipid-lowering drugs, reduction of fat
consumption and physical exercise. METHODS. Patients were prospectively
randomized either to an intervention group (n = 29) participating in regular
physical exercise or to a control group (n = 33) receiving usual care. Energy
expenditure in leisure time physical activity was estimated from standardized
questionnaires and from participation in group exercise sessions. After 12
months of participation, repeat coronary angiography was performed; coronary
lesions were measured by digital image processing. RESULTS. After 1 year,
patients in the intervention group achieved an increase in oxygen uptake at a
ventilatory threshold of 7% (p < 0.001) and peak exercise of 14% (p < 0.05),
whereas a significant decrease was observed in patients in the control group.
To achieve significant improvement in cardiorespiratory
fitness, approximately 1,400 kcal/week had to be expended in
the form of leisure time physical activity (p < 0.001). The mean energy
expended in such activity was 1,876 +/- 163 kcal/week in the intervention
group and 1,187 +/- 97 kcal/week in the control group (p < 0.001). In the
intervention group, regression of coronary artery disease was noted in 8
patients (28%), progression of disease in 3 (10%) and no change in coronary
morphology in 18 (62%). In contrast, coronary artery disease progressed at a
significantly faster rate in patients in the control group (progression in
45%, no change in 49% and regression in 6%) (p < 0.001 vs. intervention).
When the two groups were combined, the lowest level of leisure time physical
activity was noted in patients with progression of disease (1,022 +/- 142
kcal/week) as opposed to patients with no change (1,533 +/- 122 kcal/week) or
regression of disease (2,204 +/- 237 kcal/week) (p < 0.005). CONCLUSIONS.
Measurable improvement in cardiorespiratory
fitness requires approximately 1,400 kcal/week of leisure
time physical activity; higher work loads are necessary to halt progression
of coronary atherosclerotic lesions (1,533 +/- 122 kcal/week), whereas
regression of coronary lesions is observed only in patients expending an
average of 2,200 kcal/week in leisure time physical activity, amounting to
approximately 5 to 6 h/week of regular physical exercise.