Whether it be an exasperated grunt getting out of the chair, or a little bit of an extra push with the arms at the same time, age brings about a lot of changes to your body. Over time, naturally muscle mass and strength will decrease with age, and activities that once took no effort might seem a little bit more difficult than normal. This phenomenon is known as “sarcopenia”, the age-related loss in lean body mass and strength ⁽¹⁾. Although these changes are bound to occur, physical activity, and in particular resistance training and weight-bearing activity, can help you maintain both muscle mass and strength over time. As a result, functional ability can be maintained or even be improved upon, leaving you happier and stronger. Managing your muscle mass with DEXA will allow you to accurately and consistently manage your muscle mass over time, making sure you are maximising the effects of your efforts.

Generally beyond the age of 50, sarcopenia can result in the loss of skeletal muscle mass (0.5-1% per year) ⁽²⁾. While the direct cause of sarcopenia is not specifically known, we do know the impact it can have on your body. It can be characterized by a decrease in size of muscle, along with a reduction of the quality of muscle, which can be seen in an increase of fat in place of muscle fibre ⁽³⁾. These changes can in turn leave you more prone to injury and decreased quality of life. However, a simple measurement of circumference of your muscle does not give provide enough information for sarcopenia, and as such, regular DEXA scans are essential in ensuring that you are maintaining muscle mass, quality, and strength overall.

So what can you do to offset the decrease in muscle mass that occurs with age? Physical inactivity has been shown as a significant risk factor for the onset of sarcopenia. As such, exercise and nutrition are the forefront of maintenance of muscle size and strength. Engaging in regular physical activity has shown an offset in the components of sarcopenia, with one review showing progressive resistance training improved both physical performance and muscular strength in older adults ⁽⁴⁾. In combination with physical activity, protein intake plays an important role for muscle growth and development, with experts suggesting a protein intake of 1.0-1.2g/kg of body weight, dispersed through 25-30g servings per meal ⁽⁵⁾. A DEXA scan can help ensure you are completing enough physical activity and can help guide advice on macro-nutrient requirements to maintain muscle mass over time. By assessing changes in your body composition over time, you can adjust your exercise and nutrition accordingly.

In order to maintain strength and muscle mass, consistent physical activity is key. The most effective form of exercise in the management of muscle mass and strength is resistance training, or weight-bearing activity. Resistance training has shown improvements in muscle mass, muscle quality, and strength, thereby reducing the difficulty of activities of daily living. General recommendations for resistance training in older adults are currently 2-3 days of the week at a moderate to high intensity ⁽⁶⁾. However, any form of exercise carries the risk of injury. Consult with your GP or a health professional on whether it is suitable to be performing physical activity. See an Exercise Physiologist who is qualified to work with you and can bring out the best in your results by ensuring a challenging yet safe exercise program tailored to you.

Over time, the human body will inevitably slow down. Muscle mass and strength are two components that are so important to every day living, and are a part of this process. A reduction in these areas can lead to a decreased functional capacity and reduce your ability to live your life comfortably and independently, and so it is very important that you maintain muscle mass and strength as you age. By combining a DEXA scan with physical activity, you can consistently track your progress and ensure the best possible maintenance of strength and muscle mass as time goes by, keeping you happier and healthier well into the later stages of life.

JONATHON FERMANIS

B.exphys, ESSAM, AES, AEP
Accredited Exercise Physiologist

References:

1. Evans WJ. Skeletal muscle loss: cachexia, sarcopenia, and inactivity. Am J Clin Nutr. 2010;91:1123S-1127S
2. Phillips SM (July 2015). “Nutritional supplements in support of resistance exercise to counter age-related sarcopenia”. Adv. Nutr. 6 (4): 452–460.
3. Ryall JG, Schertzer JD, Lynch GS (August 2008). “Cellular and molecular mechanisms underlying age-related skeletal muscle wasting and weakness”. Biogerontology (Review). 9 (4): 213–28
4. Liu, Chiung-ju; Latham, Nancy K (8 July 2009). Cochrane Database of Systematic Reviews. John Wiley & Sons
5. Bauer, Jürgen; Biolo, Gianni; Cederholm, Tommy; Cesari, Matteo; Cruz-Jentoft, Alfonso J.; Morley, John E.; Phillips, Stuart; Sieber, Cornel; Stehle, Peter (2013). “Evidence-Based Recommendations for Optimal Dietary Protein Intake in Older People: A Position Paper From the PROT-AGE Study Group”. Journal of the American Medical Directors Association. 14(8): 542–559.
6. Porter, M. M. (2000). Resistance training recommendations for older adults. Topics in Geriatric Rehabilitation, 15(3), 60-69.