Fighting Sarcopenia

Sarcopenia (Gk, sarx, flesh, penia, poverty) in simplest terms is the age associated loss of muscle mass and functional capacity (1). It is a threat to athletes and non-athletes alike increasing the risk of both injury and disease with age. The image conjured up by the term is a frail man with a walker in his 90’s. Nothing could be further from the truth. Although decrease in muscle mass is the sign most easily recognized by the lay person, it really is the loss of functional capacity due to the aging process and disuse that define the condition. Simply put, loss of functional capacity means loss of strength and power, which involves the neuromuscular system as a whole. When considering the loss of functional capacity, due to the aging process and disuse, as the major indicator, nearly all woman and 70% of men over 50 would be at risk for sarcopenia (1).

To those of us over 50 in good shape, that’s shocking. We’re still 21 aren’t we? Reflect a little bit on that feeling before we go on. If you are 55 years old, you have experienced small changes occurring in your body for about the last ten years. You may still be quite proud of your race times and how well you can keep up with younger people, but are glad you are in the master’s division. If you are not experiencing an increasing rate of injuries, you are spending an increasing amount of time in the gym on specific exercise routines to prevent them. It is becoming increasing more difficult to come off injuries and heal them completely. You are not 21, just 55 in good shape. A natural decline, a running down of the clock, is occurring in our bodies that is out of our control and cannot be switched off. Isolating just the physiological mechanism of this decline, the main culprit seems to be a decreased rate of protein synthesis as well as a decrease in the production of anabolic hormones (1).

So does that mean we just fold, rot, turn into spindly legged pot bellied duffers who complain about our bad backs and struggle to get on and off the couch? Of course not! The deleterious effects of this decline (decreased muscle mass, decreased muscular innerviation, increased intramuscular fat/fiber), are accelerated by an aging/disuse cycle. Basically, if we don’t use our muscles and encourage the building of muscle and nervous tissue, break down of tissues is faster than build up. This leads to further decreased functional capacity of the muscle, leading to more muscle atrophy, leading to disability/injury (Ouch, my shoulder, back, knee, etc), which leads to more disuse, etc, etc. In our high stress culture where cortisol reigns supreme, where we sit at computers all day long and drive to and from work, this cycle can start to transform us into the disabled caricature described above pretty quickly. Fortunately this cycle can be broken with exercise to stimulate the anabolic (building up) response needed to counteract the breakdown.

“Well I get plenty of exercise, so why should I be concerned?” Well, because not just any exercise will do. Certainly, a variety of exercise is indicated for a healthy aging process. Yoga promotes flexibility, balance, and strength; running, cycling, and swimming promote aerobic cardiovascular conditioning; many sports and activities that require high levels of repetition promote muscular endurance. But because the sarcopenic process is a struggle between the build up and breakdown rates of muscle fiber and nervous tissue, the type II muscle fiber (with the greatest amount of active filaments and associated neural connections), the muscle fiber that produces power best, is affected most. Type II muscle fiber has more active elements and more nervous connection, which make for a faster, more powerful contraction because it does not have to depend on oxygen right away to produce energy. Type I muscle fibers have fewer active elements and nervous connections, making room for mitochondria that process oxygen to produce energy. Because of the architecture of the type II fiber and because we tend to do less power oriented (less jumping, throwing, sprinting) and heavy lifting activities as we get older and more cardio activities (walking, hiking, biking), the type II fibers are the most heavily targeted by sarcopenia. We cannot confront this loss with just balance, flexibility, cardio, or strength (learned muscle fiber recruitment). Hypertrophy (building muscle mass) and power development are required. Proper resistance training is needed for that.

Additionally, all the slow balance work and endurance training in the world won’t help you once you do start to fall. This is a hard sell for me to many clients. Because they can still run trails pretty well or stand like a stork for an extended period of time, the feel they are pretty well protected with respect to falls. This is not altogether true. Where both the aforementioned activities are beneficial and helpful to prevent and respond to a falling situation, they are not enough to counteract a fall. Fall situations are unexpected – you have lost balance and there is no range of response reaction as you might have running up or down hills. There is no initial resistance to, no preparation for, the downward movement. This means that for a split second your whole body mass is falling at a rate of 32ft/sec/sec – that’s a lot of force. Countering that force quickly (with respect to time) in order to prevent the fall is a power function, P(t) = F(t) . T(t), the domain of the type II muscle fiber. Again, resistance training is required to develop power.

Fortunately, our bodies retain the ability to build muscle mass and produce power as we age (Faigenbaum, 182). Of course, we can’t expect the same results we got at 21, but certainly enough to help us reach our objectives. And resistance training has been proven safe and effective and is indicated to build muscle mass and maintain bone density for senior citizens (1, Faigenbaum, 182). Nutrition plays a crucial role in maintaining muscle mass – one cannot expect to maintain or build mass without the proper materials. Certainly, for the specific nutritional needs and medical conditions we may develop as we age, it’s wise to confer with a nutritionist and sports physician first for specific guidelines. Also, an understanding of how the spine changes with age and use is essential whenever planning a resistance training program, but especially for those of us over 50. Like Stuart McGill, Ph.D, I am a big believer that our lumbar discs only have a set number of flexions they can endure and my goal is to have just one left on the morning of the day I die! A good strength and conditioning specialist or personal trainer is an essential resource to guide you in both the resistance training and the nutritional aspect of building muscle mass. Trying this on your own without proper guidance can be hazardous. I see silly and dangerous routines carried out by people all the time in gyms. Some they took off the internet, some are “monkey see, monkey do”, and some routines were actually provided by poor trainers. I have a list of excellent trainers. If you are a client of mine, please don’t hesitate to ask for one that best serves your needs.

A final note: You may ask, “I am not an athlete, I don’t even like exercise, why should I care? And by the way, my parents did just fine without any exercise.” My response is, “Really??” How long did they live? How easily were they able to move around? How strong and independent were they in their final years? It really is a matter of safety and quality of life more than athleticism. Some of our parent’s generation, in general, may have had a few advantages over us. They had a shorter work week and greater physicality in their activities of daily living. Despite the popularity of the PBS show This Old House, the days when people performed major chores regularly (like their own roofing or mending stone walls) that maintain attributes like balance and muscular endurance while lifting heavy loads into their 60’s are, for most part, all done (pushing a power mower and driving to the dump, although good exercise, isn’t quite the same thing). Work days are longer now, stress is higher, sit-down computer type work and continuing education are required of most us now and, with the chances of, or desire for, retirement evaporating from our culture, it’s likely you will have to remain strong and healthy at least into your 80’s. Considering working some resistance training into a few hours of your life each week would be wise.



References:
1. Peterson, Mark, PhD, CSCS*D (2010) Resistance exercise for sarcopenic outcomes and muscular fitness in aging adults. Strength and Conditioning Journal, 32(3), 52-63

2. Faigenbaum, Avery “Essentials of Strength and Conditioning, 2nd Edition” Age and Sex Related Differences and Their Implications for Resistance Exercise. Eds. Baechle, Thomas R.; Earle, Roger W. Champaign, IL, Human Kinetics, 2000

Other research material utilized:

McGill, Stuart, Ph.D.. “Low Back Disorders: Evidence-Based Prevention and Rehabilitation, 2nd Edition.” Ed. Robinson, Loarn Champaign, IL, Human Kinetics, 2007

Seguin, Rebecca, B.S., CSCS, Nelson, Miriam, Ph.D, Buchner, David, M.D., M.P.H “Strength Training for Older Adults: Growing Stronger”, Tufts University, 2002

Current Opinion in Clinical Nutrition and Metabolic Care:
January 2004 - Volume 7 - Issue 1 - pp 15-20