ANTI-AGING PROPERTIES OF WEIGHT TRAINING

Understanding The Mechanisms Of Aging

So, how exactly does aging occur? We can easily see the results of aging but there are certain biological mechanisms at work that we are often unaware of. The number cells that make up our body are kept at a relatively steady number through the process of mitosis (cells dividing) matched by the number of cells dying. This balance (homeostasis) is necessary for optimal health and body function however this equilibrium cannot be maintained indefinitely. In what is called the Hayflick limit, all animal cells have a limited number of times that they can reproduce. As we get older, senescence sets in- which is a decline in the ability of our bodies’ cells to divide. This usually starts in our early thirties and continues on throughout our lives. One prevailing theory is that the everyday occurrence of cellular reproduction leads to cumulative damage to our DNA and cells begin to die or not function correctly. This process, called apoptosis is actually beneficial as it acts a way of ‘cleaning up’ that benefits the healthy remaining cells. Taken as a whole, aging thus is nothing more than our bodies decline in being able to deal with stress. Maintaining homeostasis becomes more and more difficult until a point is reached where the organism dies. Building muscle however through the use of a well executed weight training program of sufficient intensity is a way of increasing our bodies’ potential response to stress.

As we get older, one of the main aspects working against us from being as strong and as built as we were in our younger years is sarcopenia. Sarcopenia which means literally ‘poverty of the flesh’, refers to the loss of skeletal muscle mass that comes with aging which in turn leads to weakness and frailty. For the average member of the population, as much as 50% of your skeletal muscle mass is lost between the ages of 20 and 90 years resulting in in a corresponding reduction in muscular strength. Such loss of muscle mass is usually associated as well with an increase in overall body fat. However as normal an occurrence this might be for most of us, studies suggest that lack of exercise- or more specifically weight bearing resistance exercise (like weight training) may be one of the overriding causes of sacropenia.

We don’t have to lose such large amounts of muscle mass as we age, but without an active lifestyle that incorporates some form of resistance exercise over the course of time our bodies will indeed fall victim to the syndrome of ‘use it or lose it.’ While it would be absurd to think that weight training can allow you to be strong and muscular as you were in your twenties, preliminary research shows that those who engage in intense weight training over the course of their lifetime are able to demonstrate physical qualities and abilities on par with if not exceeding that of untrained individuals in their twenties while well into their fifth decade of life. With most of our medical anti-aging focus resting on the shoulders of pharmaceutical companies trying to find a pill form solution to the combat the effects of the march of time, comparatively little is invested in researching protocols that are far less potentially lucrative such as weight training. Nevertheless, short term studies thus far do indeed show that resistance exercises like weight training increase the ability of our muscles to synthesize proteins and thus minimizing the advent of skeletal muscle decline over the years.

As we get older, it is not only our muscles that get significantly weaker without physical activity but also our bones. Increased bone porosity and reduction in bone mass can lead to the debilitating effects of osteoporosis. Which as we know can be both reversed and prevented by the implementation of weight bearing activities such as weight training.
There are some aspects however that are beyond our control, as with the advancing years comes a natural decrease in the speed of nerve conduction, reduction in peak cardiovascular ability as well as a decline in kidney and other organ function. As mentioned earlier in an explanation of the Hayflick limit- our cells have a limited number of reproductions- and as you get older the motor units (motoneurons) in your fast twitch muscles begin to die. You don’t immediately notice it, as our bodies have a remarkable system of compensating. Consider that a muscles in your leg may have 250 motor units with each motor unit having as many as a thousand muscle fibers under its control.

This ratio of motor units to muscle fiber is known as an innervation ratio and in this case would be 1,000 muscle fibers per motoneuron.

Over the course of time, those 250 motor units in your leg muscle may drop by as much as half to 125 by the time you are 70 years old, and you would think that this would make you only half as strong, but it isn’t that straightforward. You see, we lose muscle fibers at a much slower rate than motor units so you would have only lost 10% of the muscle fiber in that leg muscle by the age of 70. However, the remaining 125 motor units sprout new branches to the muscle fibers that have lost their motor units to activate them and do more work than they did before. As a result, there is a higher innervation ratio, in this example it would be let us say 1,500 muscle fibers per motoneuron as our motor units take control of more muscle fibers as a way of helping us retain our strength as we get older.

Our nervous system also slows with the passage of time and so the mechanisms of muscle contraction slows down as well. Despite these natural declines, regular resistance type exercise and an overall active lifestyle can help minimize and offset the effect of these changes in our bodies. The more muscle mass built up over time, the more strength, coordination and motor skills you will have as you get older. A point lost sadly on the millions of women who invest most of their time pursuing aerobic type exercises and lower impact activities like yoga out of a misplaced fear of developing man-sized muscles and thus curtail their involvement in weight training- the very exercises that will help them stay looking and feeling younger as the years go by. Our hormones also play a role in the reduction of our muscle mass as we get older. Testosterone, growth hormone and insulin-like growth factor (IGF) help our bodies’ build and maintain muscle mass but there is a marked reduction in production as we get older. High intensity weight training has been shown to increase all three hormones naturally and within standard human parameters. It might sound like a good idea to forgo weight training and instead turn to hormone replacement therapies but research shows that this reduction in hormones may be a key mechanism that allows us to live longer. Mammalian models with reduced growth hormone (GH) and/or IGF-1 appear to live longer and while the administration of testosterone replacement therapy for men has become a lucrative and fast growing industry here in the United States, presently available data do not justify the broad use of such hormones for anti-aging purposes. The science of Gerontology has only just started to pay attention to the amazing examples set by those engaged in a lifetime of weight training and drug free bodybuilding and research reveals that involvement in such activities can ‘create possibilities for people to age positively and reconstruct what aging “normally” means.” Such studies also highlight the self fulfilling prophecy that our society’s acceptance of advancing age as a time of disengagement, dysfunction and disease goes a long way in our not taking action to prevent it from being just that. As long as we see aging as a downward trajectory of physical and mental deterioration, we are doomed to experience it as such. One of the common perspectives of men and women involved in weight training activities over the course of their lives and who exhibit remarkable physicality into the later sixth decades of life is what was termed a ‘mondadic styled’ body. In short, they focused on who they were and what they were doing as opposed to being influenced by what society expected them to be or the examples of their peers whose aging process tended to follow the narrative of decline that we are so used to hearing. Without turning to hormonal solutions that can often cause more problems than they solve, these individuals centered themselves on following a lifestyle. A lifestyle that allows them to significantly offset the impact of aging and achieve what we are all looking for- twilight years that aren’t defined by disease and disability but by engagement with life on all levels. We don’t need drugs or DeLeon’s fabled fountain of youth, we just need to make certain forms of exercise a part of our lives at all times.