I would go so far as to say that there are only three things that you can do today to be as sure as present science allows that you have increased your remaining healthy life expectancy. The gold standard for weight of scientific evidence is a narrow platform at present:
- responsibly practice calorie restriction
- exercise regularly
- support the most proactive, plausible longevity research
None of this should really be a surprise. I'd add a fourth item for modest supplementation, but any discussion of the scientific support there gets bogged down very quickly - it's an enormously broad and complex topic, beset by a noisy band of marketeers ready to tell you anything that will make you shell out for whatever it is they're selling today.
If the future of longevity research goes the way we'd all like it to go, calorie restriction and exercise will increase - for most people - the chances of living in good health to benefit from the first real, working rejuvenation therapies. It's smart to do those easy, low cost things that raise the odds, just as it's smart to recognize that these are odds. The future is never certain, even when we're setting out to craft it in the manner we would like.
On the subject of exercise, aging and longevity, you'll find a raft of papers on PubMed from the Applied Physiology, Nutrition, and Metabolism journal. The few excepts below look at some of the ways in which regular exercise beneficially changes the operation of metabolic processes.
Although not completely understood, the mechanisms underlying the aging process may partly involve inflammatory processes, oxidative damage, mitochondrial dysfunction, and apoptotic tissue degeneration. These hypotheses are based on epidemiological evidence and data from animal models of aging, as well as interventional studies. Findings from these studies have identified possible strategies to decrease the incidence of age-related diseases and delay the aging process. For example, lifelong exercise is known to extend mean life-span, whereas calorie restriction (CR) increases both mean and maximum life-span in a variety of species. Optimal application of these intervention strategies in the elderly may positively affect health-related outcomes and possibly longevity.
moderate regular exercise attenuates oxidative stress. The mild oxidative stress possibly elicited by regular exercise appears to manifest a hormesis-like effect in nonmuscular tissues, constituting beneficial mechanisms of exercise by adaptively upregulating various antioxidant mechanisms, including antioxidative and repair-degradation enzymes for damaged molecules. Importantly, the adaptation induced by regular exercise was effective even if initiated late in life.
Reactive oxygen species (ROS) are continuously generated during aerobic metabolism. Certain levels of ROS, which could be dependent on the type of cell, cell age, history of ROS exposure, etc., could facilitate specific cell functions. Indeed, ROS stimulate a number of stress responses and activate gene expression for a wide range of proteins. It is well known that increased levels of ROS are involved in the aging process and the pathogenesis of a number of neurodegenerative diseases. Because of the enhanced sensitivity of the central nervous system to ROS, it is especially important to maintain the normal redox state in different types of neuro cells.
It appears that exercise-induced modulation of the redox state is an important means by which exercise benefits brain function, increases the resistance against oxidative stress, and facilitates recovery from oxidative stress.
The bottom line: over the long term, these sorts of changes add up to additional years of health. Exercise reduce the rate at which some of the cellular and biomolecular damage of aging accumulates, either by slowing the ongoing addition of new damage, or by modifying the processes of repair. In a future of rapidly advancing biotechnology, even a single additional year of time to wait for new therapies is a big deal. So swing the odds in your favor.