Two simple strength tests could predict how long you have left to live, a study suggests.
Researchers in New York tracked 5,400 women aged 63 to 99 years old for nearly a decade, during which about a third, or 1,900 participants, died.
At the start of the study, each woman completed two basic strength tests: A grip strength test, measuring hand grip, and a chair stand test, which measures how quickly someone can sit and rise in a chair five times unaided.
Overall, researchers found that those with the strongest grip strength had a 33 percent lower risk of death compared to those with the weakest.
For chair stand times, those who could do the test fastest had a 37 percent lower risk of death than those who completed it the slowest.
Researchers said stronger muscles could boost longevity because they help someone to stay active and keep moving independently.
They also help someone to catch themselves before a fall, which is the leading cause of injury-related deaths for those aged 65 years and older.
‘If you don’t have enough muscle strength to get up, it is going to be hard to do aerobic activities, such as walking,’ said Michael LaMonte, an epidemiologist at State University of New York, who led the study.
Scientists in New York found that people with stronger grip strength were likely to live for longer than their weaker counterparts
‘Muscular strength, in many ways, enables one to move their body from one point to another, particularly when against gravity.
‘Healthy aging is probably best pursued through adequate amounts of both aerobic and muscle-strengthening physical activities. When we no longer can get out of the chair and move around, we are in trouble.’
Although the research did not include men, scientists said it also suggests that men who are able to move independently for longer may have a lower risk of death.
In the study, published in JAMA Network Open, participants were aged 78 years old on average, and half were from a white ethnic background.
For the grip strength test, participants held a device that measures force, called a dynamometer, in their dominant hand, with their forearm parallel to the floor, and squeezed as hard as they could.
For the chair stand test, participants sat in a chair with its back against the wall and folded their arms across their chest. They did a practice stand to ensure they could do it safely before starting the test.
Overall, those with the weakest grip strength exerted a force of less than 14 kilograms (kg), which clinicians consider to mean someone has sarcopenia, a chronic condition where someone has little muscle, meaning they may struggle to lift heavy shopping bags or open tight jars.
Those with the strongest grip were able to exert a force over 24 kg, suggesting they were still able to easily carry heavy shopping and complete daily household tasks.
For the chair stand test, the weakest group took longer than 16.7 seconds to complete the five sit-to-stand movements. The strongest group took less than 11 seconds.
Researchers said they found little association between the two measurements, suggesting that they both measured different aspects of physical strength.
On average, the researchers also found that every additional seven kilograms of grip strength was linked to a 12 percent lower risk of death.
Every six-second improvement in chair stand time was linked to a four percent lower risk of death.
Even after adjusting for physical activity, walking and inflammation levels, the results were still significant, suggesting strength is an independent indicator for the risk of death.
The researchers said both measurements could be easily carried out by doctors, adding that they hoped it would be a cost-effective way to quickly check strengths in patients and highlight those who were most at risk.
Their study is the largest of its kind to examine how muscle strength relates to longevity in women over 60 years old.
The World Health Organization recommends that everyone complete 150 to 300 minutes of moderate-intensity activity every week, such as brisk walking, cycling or water aerobics.
It also recommends that everyone complete at least two strength training sessions every week.
LaMonte added: ‘Because women ages 80 and older are the fastest growing US age group, the importance of monitoring and maintaining muscular strength will have huge public health implications in the coming decades.’
