Sarcopenia – What is it?

It refers to the age-related loss of muscle bulk and power, and is one of the most important causes of age related physical decline. Lower muscle strength and bulk correlates with shorter lifespan, longer recovery times after severe illness or surgery, a higher incidence of falls and hip fractures, and a greater risk of metabolic disease. So let’s talk about this important phenomena.

There are no upsides to losing muscle.  The largest collective organ in the body, it is our primary protector.  When we trip, our muscles prevent us falling. When we hike mountains the endurance and strength capacity of our muscles (together with our cardiovascular system) enables it. Muscle is also crucially important in maintaining good metabolic health. It is highly metabolic and accounts for over 50% of our body mass. It removes glucose (sugar) from our blood and mitigates the risks of developing a range of diseases such as Type 2 diabetes and high blood pressure.

In our 40’s we begin to lose muscle unless we take action to prevent it. There is a reason we don’t see many elite athletes over 40. (Though don’t be surprised to see Andy Murray and Mark Cavendish still going when they get there.)  The underlying causes are debated, but relate to inactivity, hormonal changes, chronic inflammation and poor nutrition. Besides the visible loss of muscle bulk the physical hallmarks of sarcopenia are: loss of balance, reduced stride length when walking, an inability to rise from a chair without using your hands, or an inability to climb stairs unaided. 

Most of your muscle didn’t exist 10 years ago. Like bone, muscle protein undergoes a constant cycle of break down (MPB) and rebuilding/synthesis (MPS). However, when breakdown exceeds synthesis, you lose muscle mass. During sleep breakdown exceeds synthesis. Following most joint surgeries physiotherapy begins within hours to reduce breakdown of muscle. In the case of long-term disuse, muscle is often replaced by fat. See below image (black is fat).  

To maintain strength and agility throughout life we need to create an environment where muscle loss is minimised; where protein synthesis exceeds breakdown.

How?

1.     Ensure adequate protein intake.

2.     Regular resistance training.

Protein

Muscles need dietary protein to grow.  The required level of protein ingestion varies depending on your goals, but a good rule of thumb for those aiming to build muscle is between 1.2-1.5 g/kg of body weight. For a 70kg person that equates to 85-100grams of protein per day.  A detailed breakdown of food protein content can be found here.

Resistance training

Resistance training builds muscle at all ages. It has a remarkable ability to adapt and regenerate, however it requires regular discipline and effort.  To build muscle we must push or pull against resistance that we find difficult. Gentle movement isn’t enough. The muscle must be asked to do something at the limits of its current capability.  It then responds by taking protein from your diet and converting it into muscle.

There are many ways to incorporate resistance training into your life and not everyone needs a gym membership to do it.  A simple regime of squats, press ups, and pull ups will cover all muscle groups and can be implemented easily at home.

Why make the effort?

Maintaining muscle and avoiding Sarcopenia helps bridge the gap between lifespan (how long we live) and healthspan (how long we live in good health). It enables us to live fuller lives and navigate our environment with greater ease. But like any investment the key is to harness the value of compounding; invest small amounts of time and sweat now and realise a bigger pay off down the track. As it is for money, so too for health.

Next steps.

If I’ve managed to convince you to incorporate resistance training into your weekly routine, you need to take some steps towards it. If you are new to resistance training – or have an injury – then you may need guidance. We can help you with that.  For those with an underlying heart or health condition it is important to see your GP first.