At the risk of generalizing, it may be safe to say that regular exercise is recommended for every patient that comes to our clinic. Although an injury or physical condition may be a barrier, there is usually some level of activity that can be performed and modifications to exercises can be made accordingly (see a previous blog entitled “exercising around nagging injuries”). Quite often in the clinic, patients blame their injuries on “getting old” and may use this as a reason to reduce their activity level. Is this wise?
The Bad News…
In our body, we basically have two different muscle types; fast and slow twitch. Fast twitch fibres are responsible for the activities which require rapid, brief movements. Muscle decline due to aging preferentially targets our fast twitch fibres. Perhaps surprisingly, 55-65% of the muscles in the arms and legs are fast twitch! Why are the fast twitch fibres targeted first? One theory is that these fibres are activated (and therefore maintained) through high intensity exercise. As we age, we shy away from these activities. As a result, more fast twitch fibres are absorbed and our arms and legs seem to “shrink”. In fact, between 20 to 80 years the size of our muscle fibres decrease by 15%, while total muscle mass declines 25%.
The Good News…
Yes, our muscles have a tendency to deteriorate with age. However, highly active elderly people lose mass at a much slower rate. In fact, you can still build muscle after the age of 30! Feel sluggish because you haven’t exercised in a while? Don’t worry! It takes far less effort to regain lost strength than it does to acquire it in the first place. In fact, it has been shown that by working out once every 10-14 days athletes can retain strength, power and endurance that was gained through more rigorous training.
How Much Exercise is Necessary?
According to the American College of Sports Medicine, everyone should be exercising 3-5 x / week for 20-60 minutes each session. You should be exercising at an intensity of 60-90% of our maximum heart rate or 50-85% of your heart rate reserve.
How to Calculate Your Target Heart Rate
220 – Age = Theoretical Maximum Heart Rate (Then multiply this number by the percentage you want to exercise at). For example, if you were 40 years of age and wanted to do the minimum recommendation of the ACSM (60%), the calculation would be…
220 – 40 = 180 (Theoretical Maximum Heart Rate)
180 x .6 = 108 Beats per minute as a minimum target.
What Type of Exercise is Recommended?
From a practitioner standpoint, we recommend “everything in moderation and in perspective”. Ideally, an exercise program that encompasses resistance training as well as cardiovascular training is recommended. By keeping everything in moderation, you challenge your joints in tendons in different ways without overloading them. For example, a program that involves some running, swimming and biking as well as resistance training can allow enough variety to prevent overuse in any one area. As mentioned earlier, our arms and legs atrophy or “shrink” with age. Resistance training is important to counter this process as well as assisting with such things as our bone mineral density (which also seems to deteriorate with age). When we suggest keeping things in perspective, we’re specifically referring to the risk of injury. Perhaps for your life, setting a new dead-lift record or continuing to run with an injury is not the best idea in the long term. Unfortunately, many patients who injure themselves exercising admit that they “did something silly that day”.
Injured but still trying to exercise?
Obviously, it’s difficult to exercise if you’re in pain. Exercising around the pain is always recommended, but isn’t always easy. Have questions? Looking for help? Feel free to contact us and tell us your story. Perhaps our physiotherapist can offer you strategies for maintaining an exercise program despite your pain! firstname.lastname@example.org
Hyde TE, Gengenbach MS. Conservative Management of Sports Injuries. 2007 Jones and Bartlett Publishers Inc.