Being in poor shape in middle age hurts more than just one's physique. It is also tied to earlier death, a recent study found.
The research is the first to link physical ability among relatively young people and likelihood of dying, as study participants were all 53 years old when their fitness was measured. Previous studies have shown a similar association with older participants.
Among older people, "these observed associations may be explained by the pathways between diseases, physical capability and mortality in later life," said Rachel Cooper, the study's lead author from University College London in the UK.
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But it hadn't been clear whether physical wellbeing earlier in life affected the risk of death.
Three physical tests
To get at that question, the researchers analysed data on about 2 800 people from a national survey of those born during one week in March of 1946 in Wales, England and Scotland. All received a home visit from a nurse.
The visiting nurse assessed each participant's ability to perform three physical tests. One test gauged hand grip strength, another evaluated a person's ability to balance on one foot and the third noted the time it took the participant to stand up from a chair.
All three tests are commonly used to assess fitness in research studies.
The authors followed the participants for the next 13 years, using information from the National Health Service register to find out which had died. They took into account other factors that could influence the risk of death, including smoking, body size and a history of illnesses such as heart and lung problems at age 53.
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Presence of disease
There were 177 deaths during the follow-up period, according to the report in the British medical journal BMJ.
Cooper and her colleagues found that participants who performed in the lowest one-fifth on the tests were almost four times as likely to die during follow-up as people who completed the tasks best. Those who couldn't perform any of the tests were more than eight times as likely to die as the top performers.
The figures may reflect the presence of disease in its very early stages, the researchers write.
Performing poorly on physical tests "may provide a useful indication of underlying disease and the aging processes which are likely to be detrimental for future health, but which are not yet necessarily clinically manifest," Cooper told Reuters Health in an email.
Both strength and endurance
The study is an important addition to what was already known about physical fitness and the risk of death, researchers said, because it extends this link to people in their 50s.
"The bottom line is that people at the lowest levels of physical functioning are individuals that may be at a higher risk of adverse outcomes," said Dr. Jonathan Bean, medical director of the Spaulding Hospital for Continuing Medical Care in Cambridge, Massachusetts.
Embarking on an effort to boost fitness may combat this risk, Bean said. He recommended consulting a fitness professional or doctor before starting a new exercise programme, and emphasized the importance of building both strength and endurance.
Read: Man dies of heart attack at gym
To improve physical functioning, heart-healthy exercise such as stair climbing and walking is important. But workouts to build strength also play a key role.
Advice from experts
People should include in their regimen "exercise that is progressive in nature and involves some resistance training so you are improving your strength," Bean, who wasn't involved in the new research, told Reuters Health.
He emphasised that the ability, or inability, to perform various tasks doesn't necessarily predict a given person's lifespan.
Instead, the study is yet another sign that many people need to improve their health, such as by eating a better diet and quitting smoking, Bean said.
The message should be, "Let's improve our fitness to improve our chances of wellbeing," he said.
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