Being consistently physically active in adulthood is linked to a 30–40% lower risk of death from any cause in later life, while upping levels from below those recommended for health is still associated with a 20–25% lower risk, finds a pooled data analysis of the available evidence, published online in the British Journal of Sports Medicine.
The findings prompt the researchers to conclude that switching to a more active lifestyle at any point in adult life may extend the lifespan, and that it's never too late to start.
Currently, it's recommended that adults should aim for 150-300 weekly minutes of moderate intensity physical activity, or 75-150 weekly minutes of vigorous intensity physical activity, or a combination of the two, note the researchers.
But while these recommendations were based on the best evidence available, most of it captured measurements of physical activity at only one point in time, which might hide the potential impact of changing patterns during adulthood, they add.
The researchers therefore wanted to find out if differing patterns of physical activity, as well as its cumulative impact during adulthood, might be associated with a lower risk of death from all causes, and specifically from cardiovascular disease and cancer.
They scoured research databases for relevant studies that assessed physical activity at two or more points in time, and included in their review 85 studies published in English up to April 2024, with sample sizes ranging from 357 to 6,572,984 participants.
Fifty nine of the studies looked at long term patterns of physical activity across adulthood; 16 looked at the average benefits of different physical activity levels; and 11 explored the potential impact of cumulative physical activity on risk of death.
To overcome the challenges posed by different analytical methods used, the researchers carried out separate analyses for each of them.
Pooled data analysis of the study results showed that, overall, a higher level of physical activity was associated with lower risks of all the included outcomes.
Consistently active people (32 studies) had around a 30–40% lower risk of dying from any cause, while those who increased their levels of physical activity (21 studies) from below those recommended had a 20-25% lower risk of death from any cause.
Specifically, participants who switched from being physically inactive to being active were 22% less likely to die from any cause than those who remained inactive, while those who increased their leisure time physical activity levels were 27% less likely to do so.
On the other hand, swapping an active lifestyle for an inactive one wasn't associated with a lower risk of death from any cause.
Generally, the associations observed between a high level of physical activity and a lower risk of death were more evident for cardiovascular disease than for cancer.
Compared with participants who were consistently inactive over time, those who were consistently active, overall, or only in their leisure time, were around 40% and 25% less likely to die from cardiovascular disease and cancer, respectively.
But in general, the evidence for the associations between physical activity patterns and death from a specific cause remained inconclusive, especially for death from cancer.
The pooled data suggested that people who were consistently active or who became active had lower risks of death from any cause, and specifically from cardiovascular disease, when meeting the recommended weekly physical activity levels.
But being consistently physically active and clocking up more than the recommended maximum weekly amount of moderate to vigorous intensity exercise was associated with only a small additional reduction in risk.
Maintaining or increasing physical activity at levels below the recommended weekly amount, however, was associated with appreciable health benefits, indicating that some physical activity is always better than none, say the researchers.
And an average volume of physical activity that met the recommended weekly amount was also associated with a 30–40% lower risk of death from all causes. But more research is needed to confirm this, they add.
The researchers acknowledge some limitations to their findings, including that most of the studies included in the pooled data analyses relied on subjective assessments of physical activity, which may not always have been accurate.
And there were only a few studies that looked at cumulative amounts of physical activity, or cancer deaths.
Nevertheless, the findings have important public health implications, insist the researchers.
"First, our results emphasised the importance of [physical activity] across adulthood, indicating that initiating [it] at any point in adulthood may provide survival benefits."
They add: "As being consistently active provides greater health benefits than being previously active (ie, no longer maintaining activity), this highlights the importance of sustained [physical activity] over time.
"Future [physical activity] interventions may not only target inactive people, but also support active people to maintain their activity."
