MAKE EXERCISE A HABIT
Study finds minimum of four workouts a week needed to keep heart healthy
As the saying goes, age is just a number — that is until our bodies start telling us just how old we really are.
And while we have little control over the number of candles that light our birthday cake, we can control some of our biological aging.
The idea that there’s a mismatch between chronological age and biological age is a relatively new phenomenon, with the biggest poster child for this trend being masters athletes. A favourite subject of scientists who study aging, masters athletes typically exhibit a biological age much younger than their chronological age, suggesting that exercise may be a key component to slowing down some of the physiological decline typically associated with getting older.
A prime example of exercise’s ability to stall the hands of time was highlighted in a recent study published in the Journal of Physiology. The researchers were studying arterial stiffness, a marker of vascular disease that typically occurs with advancing age and is linked with an increased risk of stroke and heart attack. The thickening and hardening of the walls of the arteries, restricting the flow of oxygenated blood throughout the body, begins sometime after the age of 50 and, in women, is associated with the onset of menopause.
Previous studies have demonstrated a lower incidence of arterial stiffness in masters athletes who exercise six to seven days a week, a benefit that doesn’ t stretch to include less frequent and non-exercisers. This led a group of researchers from Fort Worth, Texas, to explore just how much exercise it takes to reduce arterial stiffness and whether taking up exercise later in life could reverse or diminish any changes to arterial health that have already occurred.
Using a pool of subjects from the Cooper Centre LongitudinalStudy( an exercise-based database containing more than 250,000 records from almost 100,000 people dating back to the 1970s), the researchers reviewed the data of adults who have exercised the same number of days per week for 20 years or more, dividing them into groups based on their exercise frequency. Anyone who exercised less than two days a week was considered sedentary; people who worked out two to three days a week were categorized as casual exercisers; those who exercised four to five days a week were labelled committed exercisers; and those who exercised six to seven days a week were masters athletes.
The good news for the masters and committed athletes is that their “biological aortic age” was considerably lower than casual exercisers, suggesting that a minimum of four workouts per week are needed to maintain aortic health.
But it’s not all bad news for casual exercisers.
They showed less aortic dysfunction compared to the sedentary group (who exercised less than twice a week), implying that even some exercise is better than no exercise when it comes to mitigating the effects of agerelated aortic stiffening.
But what’s really interesting about this study is the effect that a lifelong commitment to exercise has on aortic health. The study subjects, who were all in their 70s, had been exercising regularly since their mid-40s to early 50s — which is in contrast to previous studies that showed no slowing of aortic aging among older adults who took up exercise later in life. This led the researchers to herald the importance of committing to a regular aerobic exercise routine before hitting middle age if one hopes to “inhibit the adverse vascular remodelling associated with human aging.”
Does that mean we all have to take up the lifestyle of masters athletes starting in our 40s? Not necessarily. It’s worth noting that the volume and frequency of exercise needed for aortic health is consistent with the recommendation of most health agencies: 30 minutes a day, most if not all days of the week — an amount that’s achievable by a large majority of Canadians.
So if you haven’t got the message yet about the value of lifelong exercise, this is one more reason physical activity needs to be incorporated into everyone’s lifestyle as early as possible.
That said, this study looked solely at exercise frequency and volume — not intensity. Given that a significant number of studies have demonstrated that the benefits of exercise can be achieved in less time when performed at higher intensities, there may be more to learn about the optimal duration of a single bout of exercise when it comes to reducing cardiovascular risk factors.
Finally, for those already in their 50s and beyond, these findings aren’t a signal that taking up exercise later in life is a waste of time.
There’s a copious amount of research showing that starting exercise after middle age, even if it’s just two 15-minute walks at the start and end of your day, can prolong life. But for those yet to hit the big 5-0, it’s becoming clearer that the earlier exercise becomes a habit, the more likely it is that age will indeed become just a number.
This is one more reason physical activity needs to be incorporated into everyone’s lifestyle as early as possible.