How is losing your muscle mass related to staying overweight?


To a lot of people, losing muscle and gaining fat is considered a normal part of ageing.  Let’s scrap that thought right now. To a great extent, this change is probably the result of inactivity and sedentary behaviours over a long period of time. Your choices over time determine your fate.


Ok lets get real here.  Losing your muscle mass as you age is a major public health concern and many have no idea it is even happening.  Muscle wasting (atrophy) tends to begin in the mid-20’s and accelerates with age, which over time leads to a reduction in muscle cross sectional area and is seen in both men and women.  At a cellular level a reduction in both type 1 (slow twitch) and type 2 (fast twitch) fibers are seen, however predominately the type 2 fibers are affected.  The implications of this over time leads to a condition called sarcopenia (age related loss of muscle mass as we age). 


How is this loss of muscle mass related to obesity?


Sarcopenic obesity (SO) is a term used to describe the link between sarcopenia and obesity.  SO develops over time through the choices we do or do not make to maintain our health. SO is linked to inactivity and a sedentary lifestyle, which over a period of time can lead to a reduction in muscle mass, insulin resistance and potentially increase the risk of developing type II diabetes.  Let’s dive into the links here.  As I mentioned previously it is common for sarcopenia and obesity go hand in hand, as skeletal muscle tissue is extremely metabolically active and a reduction in the mass of muscle tissue can further enhance the obesity seen within an individual.  This is commonly overlooked.  Endurance training or activity plays a significant role in enhancing glucose uptake and reducing your fat mass, however it has a limited capacity to maintain your muscle mass as you age.  


From a physiological point of view, skeletal muscle tissue is the major metabolic target for glucose (carbohydrate) and triglyceride disposal (fat) and is responsible for a significant portion of our resting metabolic rate.  So if we let our muscle mass deteriorate at a significant rate as we age without doing any intervention to maintain it, we raise our risk for developing obesity, cardiovascular disease, insulin resistance and type II diabetes.

The question we need to ask ourselves: “is this a natural consequence of aging or is it due to inactivity and sedentary behaviour?” This supports the need for incorporating resistance training into your life, especially as you age, although the sooner you start, the more “strength reserve” so you’ll have a greater buffer for the ageing process.  Endurance training offers significant benefits, however combing this with strength training provides a holistic plan as you age.


Cheers to movement, strength and well-being.


Ross Kinsella

APA Titled Sports Physiotherapist

Strength and Conditioning Coach



Ross Kinsella