Recent Research into Exercise and Aging
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Like calorie restriction, regular exercise can reduce mortality and extend healthy life in laboratory animal populations. Unlike calorie restriction, it doesn't appear to extend maximum life span, but rather raises the average and lowers the incidence of age-related disease in study groups. It is hard to prove cause and effect in human life span studies, which instead use statistical methods to discover associations. Exercise is certainly associated with greater average human longevity, perhaps two to ten years at most, but again not with greater maximum life span. Despite the difficulties inherent in examining life span in your own species, it is far easier to obtain data on exercise in human populations: many more people exercise than practice calorie restriction, and many long-running studies have gathered exercise data over past decades, beginning long before the modern resurgence of interest in calorie restriction research. So if you go looking you'll find many more studies on the associations between exercise and life expectancy than exist for calorie restriction.

In contrast to the situation for epidemiological studies, there is far more work taking place on the molecular biology of calorie restriction than on the molecular biology of exercise: epigenetics, gene expression, alterations in signaling pathways, and so forth. Perhaps the most obvious measure of this state of affairs is that there are no looming drug candidates touted as exercise mimetics, akin to the several strong candidate calorie restriction mimetic compounds. I expect that parity here is just a matter of time, however. Research into the mechanisms and metabolic alterations by which exercise improves health and life expectancy will in due course catch up to the present level of interest in calorie restriction.

Now as I've said in the past, if it wasn't the case that near all of us can obtain all the benefits of exercise and calorie restriction for free, I'd ascribe more value to all of this research. As it is, I think the greatest benefit will be knowledge: greater knowledge of metabolism and the details of the progression of aging. But in comparison to the possibilities offered by rejuvenation research strategies such as SENS, the development of exercise or calorie restriction mimetic drugs is a dead end of little potential. It'll swallow up time and money and there will be very little to show for it at the end of the day, when we're all old and frail and needing something far more effective than a drug that just slightly slows down the aging process.

Here are some recent papers from the exercise research community: one epidemiological, the other a look at some of the possibly detrimental effects of antioxidants on exercise:

150 minutes of vigorous physical activity per week predicts survival and successful ageing: a population-based 11-year longitudinal study of 12 201 older Australian men

Physical activity has been associated with improved survival, but it is unclear whether this increase in longevity is accompanied by preserved mental and physical functioning, also known as healthy ageing. We designed this study to determine whether physical activity is associated with healthy ageing in later life.

We recruited a community-representative sample of 12,201 men aged 65-83 years and followed them for 10-13 years. We assessed physical activity at the beginning and the end of the follow-up period. Participants who reported 150 min or more of vigorous physical activity per week were considered physically active. We monitored survival during the follow-up period and, at study exit, assessed the mood, cognition and functional status of survivors. Cox regression and general linear models were used to estimate hazard rate (HR) of death and risk ratio (RR) of healthy ageing. Analyses were adjusted for age, education, marital status, smoking, body mass index and history of hypertension, diabetes, coronary heart disease and stroke.

Two thousand and fifty-eight (16.9%) participants were physically active at study entry. Active men had lower HR of death over 10-13 years than physically inactive men (HR=0.74). Among survivors, completion of the follow-up assessment was higher in the physically active than inactive group (RR=1.18). Physically active men had greater chance of fulfilling criteria for healthy ageing than inactive men (RR=1.35). Men who were physically active at the baseline and follow-up assessments had the highest chance of healthy ageing compared with inactive men (RR=1.59).

Sustained physical activity is associated with improved survival and healthy ageing in older men. Vigorous physical activity seems to promote healthy ageing and should be encouraged when safe and feasible.

Trade-offs between Anti-aging Dietary Supplementation and Exercise

In otherwise healthy adults, moderate aerobic exercise extends lifespan and likely healthspan by 2-6 years. Exercise improves blood sugar regulation, and resistance exercise increases or maintains muscle mass, and is associated with improved cognitive function. On the other hand, evidence for antioxidant supplements increasing longevity in humans is lacking. On the contrary, transient hormetic increases in ROS, for example associated with exercise, are actually associated with increased mammalian healthspan and lifespan.

Recent studies in humans suggest that antioxidants such as vitamins C, E , resveratrol, and acetyl-N-cysteine blunt the beneficial effects of exercise on glucose sensitivity and blood sugar regulation, likely through direct inhibition of ROS signaling. Together these results suggest that there are significant tradeoffs in the use of dietary supplementation for prevention and treatment of diseases associated with aging. Such tradeoffs may result from underlying intertwined homeostatic mechanisms. For most individuals, moderate exercise is of significant benefit.

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