By Dr. Kate Gregorevic, November 1st 2017
Sarcopenia occurs when there is a loss of muscle mass associated with a loss of function. This leads to an increased risk of falls, fractures and, if severe, loss of mobility and disability. Around 30% of women and 10% of men aged 60 and older have sarcopenia. Sarcopenia usually has multiple causes including poor nutrition, inactivity, inflammation and chronic disease. Once sarcopenia is identified there are multiple lifestyle interventions that can improve muscle function and avoid the consequences of sarcopenia.
How do people develop sarcopenia?
As we age, there is a loss of muscle mass. Muscle mass peaks in the fourth decade and from there around 1% is lost per year. As people age, there is decreased blood flow to muscles. There are also changes in the mitochondria (the powerhouses of cells), which make muscles less efficient. There can also be a loss of the number of muscle fibres, which is particularly associated with inflammation and disease.
There are also non-age related factors. Poor nutrition, particularly poor intake of protein and inactivity are the two most important. Vitamin D deficiency may also play a causative role.
How do you know if you are at risk sarcopenia?
The best way to identify loss of muscle mass is by having a body composition scan called a DEXA. This uses low energy x-rays and can look at the body composition. This also measures bone density, so can also identify osteoporosis (thin bones), which is frequently linked with sarcopenia.
The clinical definition of includes not only low muscle mass, but also impaired function. There are some simple questions based on everyday activities that can predict if you are at risk:
- Do you have difficulty rising from a chair?
- Do you have trouble walking across a room?
- Do you have trouble climbing a flight of stairs?
- Are you able to carry something heavy? (eg grocery shopping)
- Have you had any falls?
If any of these questions raise concerns, you may be at risk for sarcopenia and associated adverse outcomes.
Why is poor muscle strength a problem?
If muscle mass and strength fall below a critical level, it can cause difficulties with simple activities of daily life, like carrying laundry. At a more significant level, it can even cause difficulty with essential activities like getting off the toilet. People with sarcopenia are also more likely to fall. Due to the association with sarcopenia and osteoporosis, this can then lead to fractures.
What can you do to improve sarcopenia?
It is important to understand that muscle mass itself doesn’t just predict outcomes like falls and fractures. Even if there is a relative loss of muscle, you can still take steps to improve strength and function and lessen the risks of adverse outcomes:
- Resistance exercise – we all know that muscles can get stronger with use. This is true at any age and stage of life. Resistance exercise is a form of exercise that makes your muscles work against a force. This can start as simple exercises like standing from a chair without using your arms five times. If you are new to resistance training, it is best to get the advice of an exercise physiologist who has experience working with older adults.
- Balance and stability training – while balance training won’t necessarily improve muscle strength, this can decrease the risk of falls. This can be undertaken simultaneously with resistance training.
- Protein intake – In a study that looked at the effect of resistance training for older adults with sarcopenia, those who also had supplementation with high quality protein gained more muscle and strength. This can be achieved with supplements, but also with inclusion of high protein foods in the diet, like dairy.
- Vitamin D – for those who are deficient in vitamin D, taking a supplement can also improve muscle strength. This will also help to strengthen bones and prevent osteoporosis. This should be taken as a low daily dose as intermittent high doses can increase the risk of falls.
Like so many aspects of ageing the risk for sarcopenia is cumulative, which means that it is never too late to take action. Studies have shown that even the frailest older adults can improve their strength with exercise. Maintaining independence throughout life is a huge priority for most people. Taking steps to optimise muscle health is a key step in healthy ageing.
Please note, this article contains general education and should not be interpreted as specific medical advice. If this article raises any health or other concerns, please consult your own medical practitioner.