Life Extension - Treatment - Lifestyle intervention

Exercise - updated: 03 February 2009

Changes in cognition and mortality in relation to exercise in late life: a population based study

PLoS ONE. 2008 Sep 1;3(9):e3124

Middleton LE, Mitnitski A, Fallah N, Kirkland SA, Rockwood K.

BACKGROUND: On average, cognition declines with age but this average hides considerable variability, including the chance of improvement. Here, we investigate how exercise is associated with cognitive change and mortality in older people and, particularly, whether exercise might paradoxically increase the risk of dementia by allowing people to live longer. METHODS AND PRINCIPAL FINDINGS: In the Canadian Study of Health and Aging (CSHA), of 8403 people who had baseline cognition measured and exercise reported at CSHA-1, 2219 had died and 5376 were re-examined at CSHA-2. We used a parametric Markov chain model to estimate the probabilities of cognitive improvement, decline, and death, adjusted for age and education, from any cognitive state as measured by the Modified Mini-Mental State Examination. High exercisers (at least three times per week, at least as intense as walking, n = 3264) had more frequent stable or improved cognition (42.3%, 95% confidence interval: 40.6-44.0) over 5 years than did low/no exercisers (all other exercisers and non exercisers, n = 4331) (27.8% (95% CI 26.4-29.2)). The difference widened as baseline cognition worsened. The proportion whose cognition declined was higher amongst the high exercisers but was more similar between exercise groups (39.4% (95% CI 37.7-41.1) for high exercisers versus 34.8% (95% CI 33.4-36.2) otherwise). People who did not exercise were also more likely to die (37.5% (95% CI 36.0-39.0) versus 18.3% (95% CI 16.9-19.7)). Even so, exercise conferred its greatest mortality benefit to people with the highest baseline cognition. CONCLUSIONS: Exercise is strongly associated with improving cognition. As the majority of mortality benefit of exercise is at the highest level of cognition, and declines as cognition declines, the net effect of exercise should be to improve cognition at the population level, even with more people living longer.

Publication Types:

• Review

Exercise interventions for dementia and cognitive impairment: the Seattle Protocols

J Nutr Health Aging. 2008 Jun-Jul;12(6):391-4

Teri L, Logsdon RG, McCurry SM.

Research evidence strongly suggests that increased physical exercise may not only improve physical function in older adults but may also improve mood and slow the progression of cognitive decline. This paper describes a series of evidence-based interventions grounded in social-learning and gerontological theory that were designed to increase physical activity in persons with dementia and mild cognitive impairment. These programs, part of a collective termed the Seattle Protocols, are systematic, evidence-based approaches that are unique 1) in their focus on the importance of making regular exercise a pleasant activity, and 2) in teaching both cognitively impaired participants and their caregivers behavioral and problem-solving strategies for successfully establishing and maintaining realistic and pleasant exercise goals. While additional research is needed, initial findings from randomized controlled clinical trials are quite promising and suggest that the Seattle Protocols are both feasible and beneficial for community-residing individuals with a range of cognitive abilities and impairments.

Publication Types:

• Review

Physical Activity and Cognitive Health

Alzheimers Dement. 2007 Apr;3(2):98-108

Jedrziewski MK, Lee VM, Trojanowski JQ.

BACKGROUND: The industrialized nations are experiencing a demographic revolution due to the continuing increase in longevity and the rapid rise in the percentage of the population over 65 years old. Interventions that promote healthy aging will continue to gain significance as efforts to delay disability and loss of function intensify. METHODS: Since physical activity has been implicated in promoting healthy aging, here we review a large body of research that examines physical activity and cognitive health. Specifically, we focus on the associations of physical activity with cognitive function and dementia, including prevention, delay or slowing down of disease progression. Thus, we have prepared a descriptive review of the literature including various types of publications, prospective cohort, case-control, clinical trial and meta-analysis papers, published since 1999 in peer-reviewed journals. RESULTS: Based on currently available data, we conclude that the relative risk of cognitive decline with aging may diminish in individuals who are physically active; however, this has not been definitively demonstrated thus far. CONCLUSIONS: Further research is needed to determine conclusively the effects of physical activity on cognitive function and dementia and to elucidate the basis for this linkage.

Publication Types:

• Review

Physical activity and cognition in old age

Curr Opin Psychiatry. 2006 Mar;19(2):190-3

Lautenschlager NT, Almeida OP.

PURPOSE OF REVIEW: With the rapid ageing of the world's population, investigating protective factors that may prevent or delay age-related disorders has become a new public health priority. Dementia is a common age-related disorder, affecting up to one in every two people reaching 80 years of age or above. Amongst the various potential 'protective factors' currently under investigation, physical activity seems to hold promise for the primary and the secondary prevention of dementia. This paper critically reviews the evidence in support of the association between exercise and cognitive decline/dementia, as reported by cohort studies or clinical trials. RECENT FINDINGS: The results of cohort studies show that physical activity is associated with better cognitive function and less cognitive decline in later life although there is only scant evidence suggesting that physical activity may in fact reduce the risk of dementia and Alzheimer's disease. In addition, data to support the systematic introduction of physical activity programmes to reduce the risk of dementia in later life are not as yet available from randomized clinical trials. SUMMARY: The results of observational studies are largely consistent with the hypothesis that physical activity reduces the risk of cognitive decline and dementia in later life. These findings are, however, not as yet adequately supported by data from randomized clinical trials.

Publication Types:

• Review

Resistance training, sarcopenia, and the mitochondrial theory of aging

Appl Physiol Nutr Metab. 2008 Feb;33(1):191-9

Johnston AP, De Lisio M, Parise G.

Skeletal muscle aging is associated with a significant loss of muscle mass, strength, function, and quality of life. In addition, the healthcare cost of aging and age-related disease is growing, and will continue to grow as a larger proportion of our population reaches retirement age and beyond. The mitochondrial theory of aging has been identified as a leading explanation of the aging process and describes a path leading to cellular senescence that includes electron transport chain deficiency, reactive oxygen species production, and the accumulation of mitochondrial DNA deletions and mutations. It is also quite clear that regular resistance exercise is a potent and effective countermeasure for skeletal muscle aging. In this review, we discuss age-related sarcopenia, the mitochondrial theory of aging, and how resistance exercise may directly affect key components of the mitochondrial theory. It is clear from the data discussed that regular resistance training can effectively disturb processes that contribute to the progression of aging as it pertains to the mitochondrial theory.

Publication Types:

• Review

Publication Types:

• Review