When it comes down to it, the most important reason to exercise is its effect on health and longevity. Statistically, exercisers live longer than non-exercisers. But it's not only the extra years that make a difference. An active lifestyle increases the chances those years will be lived doing the things you love to do.
Aging is inevitable, but the longer you can maintain the strength, endurance and mobility needed to live independently, the better your quality of life. But there's also a collective benefit of aging in good health. A healthier community means fewer people in extended care and more families spending quality time with their loved ones.
You'd think with so much to gain, more of the population would be active. But less than 50 per cent of Canadians work up a sweat on a regular basis.
Establishing an exercise routine early is one of the ways to ensure a more active population. Acquiring a love for physical activity at a young age increases the chances of exercise becoming a lifelong habit. Like fit adults, fit kids are stronger, healthier and less likely to carry unwanted weight than their sedentary peers. But do the fitness and health benefits acquired at a younger age stick with us as the decades march on?
It's a great question, considering most of us experience periods in our lives where regular physical activity takes a backseat to other responsibilities. The stress of starting university, a new job or moving houses, the demands of a young family, aging parents or sick family member or your own health issues can cause an interruption in exercise routine. Sometimes that interruption is only a few days or a few weeks, but for some people it can be decades before they head back into the gym.
Given it's not unusual to experience periods of inactivity over a lifecycle, what kind of impact does going from active to inactive have on health and longevity? Are the benefits accrued through years of working out at risk of being lost if you hit pause on your exercise routine? Or does an investment in physical activity always have a return, even if it's been decades since you last pulled on a pair of gym shorts?
Interestingly, research on the consequences of an exercise habit that ebbs and flows over a lifetime is limited, which is why an international team of researchers took a deep dive into studies assessing the effect physical activity has on all-cause mortality, cancer and cardiovascular disease across adulthood.
"This review provides the first and currently largest meta-analysis of quantitative estimates of risk reduction for different mortality outcomes based on different physical activity patterns," the researchers said.
Not surprisingly, the data confirms higher and more consistent patterns of physical activity resulted in greater longevity, including 20-40 per cent lower risk of all-cause mortality and 30-40 per cent lower risk of cardiovascular disease mortality.
But there's an interesting caveat.
"Our results suggest that risk reductions were more evident in people who were consistently active in leisure time than those with consistently high total physical activity levels," the researchers said.
This implies a physically demanding job may not offer the same health benefits as the type of purposeful physical activity undertaken outside of work, like going for a swim, bike, walk or run.
Also revealed is exercise didn't have as strong an effect on cancer as it did on cardiovascular disease or all-cause mortality. Pending more investigation, the researchers hypothesize the results may reflect the reality exercise lowers the risk of some, but not all types, of cancer.
Similarly confirmed is it's never too late to reap the benefits of exercise, with late-comers experiencing a similar boost in health and longevity as those with a lifetime exercise habit. Even those who fall just short of accumulating the recommended 150 minutes of moderate to vigorous physical activity a week still improve longevity and reduce their risk of chronic disease.
What is a novel finding, however, is study subjects whose activity levels dipped from active to inactive didn't experience a matching reduction in longevity.
"Our additional analyses illustrated potential risk reductions for people with decreasing physical activity patterns, which suggested a possibility of the 'bank-saving' hypothesis, that previously accumulated physical activity might provide health benefits in later life stages," the researchers said.
In other words, health gains acquired from being active earlier in life may stick with you longer than previously thought. But that doesn't mean you can coast through life relying on your formerly active lifestyle to keep you healthy during your golden years. There are plenty of exercise benefits to be enjoyed in the short term, including lowering stress levels, improving sleep and boosting energy. And as previously stated, a longer life isn't the only goal. Actively engaging with friends and family while pursuing your favourite pastimes is arguably the definition of your best life. To achieve that at any age, exercise, started at any time in life, is the best medicine.