New research into preventing muscle loss during hospitalisation

Even a short hospital stay can lead to significant muscle loss in older people within a few days. This has far-reaching consequences for mobility, independence and quality of life. Maastricht UMC+ is therefore launching a large-scale scientific study into ways of preventing muscle loss during illness and hospitalisation. The research team aims to preserve muscle mass, even when movement is difficult, through a combination of light muscle activity and targeted nutrition. Thanks to a grant worth millions from De Weijerhorst Foundation, this research can now get underway.

Muscle loss is often seen as an inevitable consequence of ageing, but that image is incorrect. According to lead researcher Luc van Loon, professor of Exercise and Nutrition Physiology, it is mainly short periods of inactivity that cause muscles to weaken rapidly. ‘It is not old age itself, but periods of inactivity during hospitalisation, surgery or illness that can lead to significant loss of muscle mass and strength within a few days,’ he says. In older people, this loss is often not fully recovered. Because they are more often ill and more often hospitalised, periods of little movement accumulate. During illness, the natural balance in muscles is also disrupted: people move and eat less, and muscles respond less well to proteins, a phenomenon known as anabolic resistance. The result is accelerated breakdown of muscle tissue. The impact is significant: one week of bed rest can lead to a loss of almost one and a half kilograms of muscle. 

Focus on retention

What disappears in a short period of time takes months to rebuild. That is why the new research focuses on preventing muscle and strength loss.  ‘A lot of research has been done on how to train muscles to the maximum, for example in sports,’ says Van Loon. ‘We are asking a different question: what is the minimum required to prevent or significantly reduce muscle loss during illness or bed rest?’ The researchers are specifically looking for simple and feasible solutions. For example: getting out of bed more often for short periods, walking a short distance, or cycling gently in bed with a special bed bike. 

For patients who are unable to move or can only move very slightly – for example, due to a cast, serious illness or admission to intensive care – the team is investigating alternatives. One of these is light electrical muscle stimulation (NMES). Electrodes on the skin induce muscle contractions that resemble movement. ‘It is not a substitute for real movement,’ emphasises Van Loon, ‘but it can help to slow down muscle loss when movement is temporarily impossible.’

Combining exercise and nutrition

In addition to activity, nutrition plays a central role in the research. The researchers are studying whether adding specific amino acids, the building blocks of proteins, to meals can help to better support muscles during inactivity. These amino acids send a powerful signal to muscles to maintain muscle tissue. By adding them in small amounts, the researchers expect to be able to limit muscle and strength loss during bed rest.

From lab to hospital

The first studies are being conducted on healthy young and older volunteers in a controlled research environment. For example, they undergo a week of bed rest or have a leg temporarily immobilised. During this period, researchers carefully measure changes in muscle mass, muscle strength and the response of muscles to nutrition and activity.

Once it is clear which approach is most effective, the next step is implementation in the hospital. Think of patients recovering from hip or knee surgery, or elderly people who are admitted with pneumonia or flu, for example. Together with dieticians, physiotherapists and nurses, the team investigates how these interventions can become part of standard care.

About De Weijerhorst Foundation

De Weijerhorst Foundation supports medical scientific research. Every year, the foundation invests in projects that contribute to better care and a higher quality of life for patients. Drs. Harrie Hox, chairman of De Weijerhorst Foundation, emphasises the importance of supporting medical scientific research. ‘We see it as our social responsibility to stimulate medical progress, among other things. The projects we support focus on social importance and direct relevance to quality of life. This project contributes to the prevention of muscle loss, enabling patients to recover more quickly and resume their daily lives.’