Exercise! But How Much Do You Need to Get Healthier?
Recent studies suggest that it is probably less than you think.
Wanna age gracefully? One of the most important prescriptions I can give you is to get regular physical activity. Still, fewer than 1 in 5 Americans gets the minimum recommended amount. If you are capable of doing so, aim for at least 2.5 hours of moderate intensity aerobic exercise each week. Examples of such activities include:
- Walking briskly
- Full-body strength workouts
Why should you be diligent about achieving such goals? You may reduce your risk of a myriad of health maladies. Here are some of the conditions for which you are reducing risk:
- heart disease
- diabetes, type 2
- colon cancer
- breast cancer
- diminished cognitive function
But what if you are unable to achieve the minimum recommended amount of physical activity? Even if you are doing less, it is probably effective. This observation is the subject of my communication with you today.
A January 2020 study illustrates the fact that even extremely short (but intense) bursts of exercise can offer cardiovascular health benefits. Let’s look at the results of this study.
The sedentary young adults climbed three flights of stairs for three times a day. They did this three days per week, over a cumulative six weeks. Before (and after) the climbs, the study participants warmed up (and cooled down). Researchers asked the subjects to climb the stirs as quickly and safely as they were able, one step at a time. Here are the findings, after six weeks:
Cardiorespiratory (aerobic) fitness improved by 5 percent. Power increased by 12 percent, using a cycling test.
It works for older (and less healthy) folks, too
Do we older folks benefit from minimal exercise, say in the form of walking for only 30 minutes each morning? Let’s turn to the effect of morning exercise with or without breaks in prolonged sitting on blood pressure in older overweight or obese adults. The study authors show physical activity improves health:
“Just 30 minutes of walking in the morning kept blood pressure lower, on average, throughout the day. The effect was more pronounced in women when they also took short (3 minute) walking breaks every half-hour.”
Reflect on that: Three minute walking breaks every half-hour. Remarkable.
Physical activity and heart health
I especially love the next study, in part because it is so illustrative of how little it takes to improve your health.
A little exercise really facilitate a healthier life, even for individuals with serious heart disease, according to a 2017 study published in the Journal of the American College of Cardiology.
Researchers across the globe collected physical-activity information from over 15,000 people with heart disease and at least one other risk factor (such as diabetes) who had had had something like a heart attack.
Just 10 minutes of brisk walking each day — or 15 to 20 minutes of slower walking — was associated with a 33 percent lower risk of dying, scientists pointed out in an editorial that accompanied the study.
Perhaps not surprisingly, the study showed that those did the most physical activity (at the hardest levels) were the least likely to die during the period studied.
But there was also hopeful news for those with known heart disease, for whom high-intensity exercise may not be possible. For the subjects who started off in the worst shape — sedentary, and with additional problems such as shortness of breath — the scientists found significant benefits to be associated with even small amounts of regular activity. This suggests that when it comes to moving, those at the highest risk actually have the most to gain.
While the study results show that while more exercise is indeed better, physical activity at levels far below current health recommendations is associated with significant health benefits for people with heart disease.
Does exercise have psychological benefits?
Researchers reported the results of a cross-sectional study examining the association between physical exercise and mental health. They looked at 1.2 million individuals in the United States between 2011 and 2015.
The investigators compared the number of days of bad self-reported mental health between individuals who exercised and those who did not, using statistical methods (called exact non-parametric matching) to balance the two groups in terms of a myriad of factors, including in the health domain.
In this large US sample, physical exercise was significantly and meaningfully associated with self-reported mental health burden in the past month. More activity was not always better. The bottom line:
Those who got regular exercise had fewer days when they reported feeling stressed or depressed than their sedentary counterparts.
Dementia risk drops, too.
One of my greatest fears is dementia. The good news for you and me? Even small amounts of physical activity may cut dementia risk. A decade-long study looked at folks older than age 65 years. Researchers found these provocative results:
“Those who were active thrice weekly for 20 minutes at a time reduced by a fifth the chances of having cognitive impairment severe enough to require moving to a full-time-care facility.”
What about premature death?
You already know the answer. As you transition from no activity to some, you can see a significant drop in the risk of premature death from any cause. While you may see a continued added benefit with additional amounts, the most significant jump is from being sedentary to doing something.
Hadassah-Hebrew University Medical Center (Israel) researchers tracked men and women between 70 and 95 years who lived at home. The researchers tracked men and women between the ages of 70 and 95 who lived at home. They asked how often each person left the house per week on average, and then tracked how long they lived.
Those who left home most frequently — whether on their own or with assistance — were much less likely to die during the 25-year follow-up period, than those who tended to stay home. Looking more closely, we find:
- Seventy-one percent of those who left home almost daily at age 78 lived to age 85; in comparison, only 44 percent of those who rarely went out survived that long.
- Seventy-four percent of those who headed out every day at age 85 lived to 90, while only 41 percent who stayed home lived that long.
Now, I would be remiss not to register an objection: This study was observational. Was it leaving home that led to living longer? Maybe more healthy folks were more likely to leave. Still, there is no significant downside to getting out of the house and to keep moving. You are likely to feel better and to have a better quality of life.
Bottom line: Move!
Move any way you’re able to. Every little bit counts. Can’t walk? Move, if you are able. Turn side-to-side, get those arms and legs moving. Try five minutes, then take a break as needed. If you can do more, do more. Of course, check in with a valued health care provider first, and if you are a beginner, start exercising slowly. You can always build up gradually.
For many, that means a brisk walk for ten minutes, three times daily. For many of us, taking a walk is simple, and perhaps the most under-appreciated form of exercise.
I’m Dr. Michael Hunter. I thank you for joining me and I hope you have a joy-filled weekend.