Correspondence
Exercise Training for Very Elderly People
N Engl J Med 1994; 331:1237-1238November 3, 1994
- Article
To the Editor:
In their discussion of exercise training for physical frailty in very elderly people (June 23 issue),1 Fiatarone et al. compare resistance training with endurance training, stating that “endurance training has generally resulted in relatively small physiologic and functional benefits in nursing home residents.” There are too few published studies in this area to draw conclusions about the advantages of resistance training over endurance training for elderly nursing home residents. Have these two types of exercise training been compared with follow-up in frail nursing home residents? In a population of people who often have impaired mobility and multiple concurrent conditions, it is important to avoid criticizing any effort to increase physical activity as being of little benefit, particularly when this has not been shown to be true. In our area, media reports on the article by Fiatarone et al. could be misconstrued by an uninformed public as meaning that there is little to be gained from participating in less strenuous activity, such as walking.
It would be wonderful if the benefits of resistance training proved to be long-lasting and resulted in general improvements in physical functioning and health. However, it would be unfortunate if this research diminished an appreciation of the benefits that people may gain from other types of activity that produce less dramatic increases in muscle mass and strength than does resistance exercise. The reported benefits of such activity include greater mobility, reduced risks of functional loss and depression, improved lipoprotein profiles, and longer survival.2-4
4 ReferencesSuzanne G. Leveille, R.N., M.N.
Andrea Z. LaCroix, Ph.D.
Group Health Cooperative of Puget Sound, Seattle, WA 981011
Fiatarone MA ,O'Neill EF ,Ryan ND , et al. Exercise training and nutritional supplementation for physical frailty in very elderly people. N Engl J Med 1994;330:1769-1775
Full Text | Web of Science | Medline2
LaCroix AZ ,Guralnik JM ,Berkman LF ,Wallace RB ,Satterfield S . Maintaining mobility in late life. II. Smoking, alcohol consumption, physical activity, and body mass index. Am J Epidemiol 1993;137:858-869
Web of Science | Medline3
Wagner EH ,LaCroix AZ ,Buchner DM ,Larsen EB . Effects of physical activity on health status in older adults I. Observational studies. Annu Rev Public Health 1992;13:451-468
CrossRef | Web of Science | Medline4
Duncan JJ ,Gordon NF ,Scott CB . Women walking for health and fitness: how much is enough? JAMA 1991;266:3295-3299
CrossRef | Web of Science | Medline
To the Editor:
Fiatarone et al. show that high-intensity weight training reduces weakness and frailty in the very elderly and conclude that low muscle mass and weakness impair mobility, independently of chronic disease and other characteristics of old age. However, they do not describe the correlation between a change in strength and the burden of chronic disease.
Adaptability to exercise training may be inversely related to the burden of chronic disease. In the study by Fiatarone et al., the weakest subjects benefited the most, unless they had severe muscle atrophy. By inference, the weakest and frailest subjects benefited much less than their more robust peers. Previous studies suggest similar results. Among patients undergoing hemodialysis, exercise training failed to increase aerobic capacity in the patients with the highest burden of disease.1 Among patients with angina pectoris, those with the largest change in the submaximal rate-pressure product as a result of training had the highest threshold for angina.2 Among previously sedentary men who engaged in exercise training, those with the largest increases in high-density lipoprotein cholesterol concentrations had the highest base-line concentrations.3 It appears that healthier people derive more benefit from exercise training than less healthy people do. Maybe the elderly patients with atrophy had myopathic processes resistant to adaptation, which blunted their response to exercise training.
The findings of Fiatarone et al. confirm that exercise training works despite frailty and chronic disease, but the authors have not shown that skeletal-muscle adaptations are independent of chronic disease. Instead, their data raise again the disquieting possibility that physical training has the least benefit for those who need it the most.
3 ReferencesGeoffrey E. Moore, M.D.
University of Pittsburgh Medical Center, Pittsburgh, PA 152131
Moore GE ,Parsons DB ,Stray-Gundersen J ,Painter PL ,Brinker KR ,Mitchell JH . Uremic myopathy limits aerobic capacity in hemodialysis patients. Am J Kidney Dis 1993;22:277-287
Web of Science | Medline2
Thompson PD ,Cullinane E ,Lazarus B ,Carleton RA . Effect of exercise training on the untrained limb exercise performance of men with angina pectoris. Am J Cardiol 1981;48:844-850
CrossRef | Web of Science | Medline3
Williams PT ,Wood PD ,Haskell WL ,Vranizan K . The effects of running mileage and duration on plasma lipoprotein levels. JAMA 1982;247:2674-2679
CrossRef | Web of Science | Medline
Author/Editor Response
Dr. Fiatarone replies:
To the Editor: Moore states that adaptability to exercise training may be inversely related to the burden of chronic disease. However, as we state in the Results section of our article, there was no relation between medical diagnoses and changes in muscle function after training. The only two characteristics that were directly related to exercise adaptation were a low level of muscle strength and a large reserve of total-body potassium at base line. Thus, the weaker subjects benefited more, not “much less,” than their stronger peers.
We do not agree that healthier people derive more benefit from exercise training. Most studies of elderly subjects indicate that the largest relative gains in muscle strength and aerobic capacity occur in those with the lowest base-line values. In addition, healthy, unimpaired subjects do not have the functional gains, such as improved mobility, seen in our subjects.
Moore suggests that elderly patients with atrophy may have myopathic processes resistant to adaptation. However, it should be noted that all our subjects had muscle atrophy, yet all 50 exercisers had a response to resistance training, with increases in muscle strength. Since much of the short-term adaptation to resistance training appears to be attributable to changes in neural factors and independent of muscle hypertrophy, our study supports the persistence of this neural adaptation among very frail elderly people with a high burden of chronic disease. Thus, physical training appears to be most beneficial for those who need it the most, contrary to Moore's suggestion.
Leveille and LaCroix suggest that it is premature to draw conclusions about the relative merits of resistance and endurance training in nursing home residents and that other forms of activity should not be “criticized.” However, given the cost of long-term care and the time and personnel involved, a therapy that has been shown to improve muscle strength and mass, walking, stair climbing, the level of overall activity, and energy consumption and that can be used even if walking is not feasible seems preferable to less effective or less feasible interventions.
Walking itself has not been shown to decrease falls or risk factors such as lower-extremity muscle weakness or balance disorders. There seems little reason at present to recommend walking for these specific purposes, though it is clearly useful for others. Our conclusions pertain only to the nursing home population, and the evidence to date in this population supports resistance training rather than endurance training. If the media have unfairly extrapolated our findings to other health outcomes or other populations, we hope this response clarifies our study and its implications.
Maria A. Fiatarone, M.D.
Tufts University, Boston, MA 02111- Citing Articles (1)
Citing Articles
1
S. Wurm, M. Wiest, C. Tesch-Römer. (2010) Theorien zu Alter(n) und Gesundheit. Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz 53:5, 498-503
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