Ageing like fine wine is a dream for many. But are you truly ageing well, or are you gradually losing your physical independence? Most importantly, how can you determine whether you are ageing well? What if a simple 30-second sit-to-stand test could predict it? Emerging research shows that this functional test can forecast your risk of falls, hospitalisation, and even mortality. The findings of the study are published in the Journal of Sport and Health Science.
Understanding Ageing and the Role of Muscles
One of the major demographic challenges of the 21st century is the ageing global population. While advances in medicine over the last decade have increased life expectancy, the real challenge is ensuring these additional years are lived with independence and a good quality of life. Muscle function plays an important role in ageing. It is often the factor that determines whether older adults remain independent or develop functional limitations and geriatric syndromes.
As you age, the musculoskeletal system is particularly affected. This decline begins in your 30s and accelerates significantly after 60. Several biological changes contribute to this deterioration. As you age, the fast-twitch muscle fibres responsible for generating rapid and powerful movements progressively decrease in number and size. The nervous system also becomes less efficient at activating these muscle fibres, while fat and connective tissue start to build up within them. All of these changes make it harder to move quickly and generate force.
Different studies have shown that muscle power declines earlier and faster than other components of the musculoskeletal system, dropping by about 2–3% per year, compared with 1.0–1.5% per year for muscle strength and about 0.5–1.0% per year for muscle mass. Among the components of muscle function, muscle power is an important indicator of healthy ageing. It is essential for daily movements such as walking and climbing stairs.
How to Measure Muscle Power?
Traditionally, measuring muscle power was an expensive process requiring sophisticated equipment. However, Alcázar et al. developed a validated equation based on a simple functional test: the sit-to-stand (STS) test. You can do this at home, and it is very easy. All you need is a chair. Set a timer for 30 seconds and stand up and sit down as many times as possible within that time, with your arms crossed over your chest. Using a formula (or the POWERFRAIL app) that accounts for body weight, height, and repetitions, anyone can estimate their muscle power without special equipment. These values can then be normalised to body mass to obtain relative STS power.
What the Data Reveals
To better understand the role of muscle power in healthy ageing, the researchers analysed data from 1,876 older adults aged 65 years and above from the Toledo Study for Healthy Ageing, a large population-based cohort study conducted in Toledo, Spain. The researchers calculated each participant’s relative STS power using the test and the Alcázar equation. They found that those with low relative STS power faced significantly higher risks across multiple health outcomes.
In men, low relative STS power was associated with a higher likelihood of previous fractures of all types and falls. In women, the pattern was slightly different. Those with low relative STS power had a higher chance of previous hip fractures. This trend was also observed for previous falls and all types of fractures.
During a follow-up period of six years, women with low relative STS power had a 29% higher risk of hospitalisation. They also tended to spend more days in hospital compared with women with normal relative STS power.
The mortality results were striking. Men with low relative STS power had a 57% higher risk of all-cause mortality compared with those with normal relative STS power. In women, the link was even stronger. Women with low relative STS power had more than double the risk of death (104% higher) during the follow-up period (nine years).
So, this 30-second test can reveal a great deal about your risk of falls, hospitalisation, and even death.
