Exercise: It does so much more than burn calories

Elizabeth Pegg Frates, MD

If you’re trying to lose weight, you’ve surely heard that you need to “eat less and exercise more.” The more you move, the more calories you’ll burn — and you’ll lose weight. But as it turns out, the effect of physical activity on human physiology may be a lot more complicated than that.

In a report recently published in Current Biology, researchers explored the relationship between exercise and “energy expenditure” (calories burned). This study monitored the physical activity and corresponding total energy expenditure in 322 men and women in North America and Africa.

What the researchers found was a little surprising. Physical activity did increase energy expenditure as expected, but only up to a point. Physical activity was monitored by accelerometers, which measure counts (units of “motion”) per minute per day, taking into account motion and velocity. At lower levels of activity, increasing the counts per minute per day did increase energy expenditure. However, with higher mean counts per minute per day, increasing counts did not increase energy expenditure, indicating a ceiling effect. So in this study, after a certain point, more exercise did not equal more energy used.

Based on their findings, the study investigators encourage that we reconsider current public health messages that state more exercise equals more energy expended, as this is not always the case.

These study results notwithstanding, whether you’ve yet to get in gear on your New Year’s exercise resolutions or you’re already an inveterate exerciser, it’s important to know that the benefits of regular physical activity go beyond burning calories. For example, 150 minutes of moderate to vigorous intensity physical activity per week can significantly decrease the risk of dying prematurely. How? By lowering blood pressure and resting heart rate, and increasing nitric oxide levels, which serves to open up blood vessels. It also increases levels of beneficial HDL cholesterol and lowers levels of damaging LDL cholesterol. In addition, regular physical activity increases insulin sensitivity. This is especially important for people with diabetes — and it can also help you avoid the disease in the first place.

Exercise can also help enhance our cognitive skills — it’s true that what is good for the heart is good for the brain. Research demonstrates that regular exercise can actually increase the size of the hippocampus, an area of the brain involved with memory. There are important mental health benefits to be gained as well. Studies suggest that for some people with depression, exercise may improve mood and symptoms just as well as medication can. In addition, a five-minute bout of exercise has been demonstrated to reduce a person’s state of anxiety.

If you’re trying to slim down, exercise is an important part of a healthy way to lose pounds. Moderate physical activity can help you burn more calories. And the good news is you don’t need to train for a marathon to get in shape. But perhaps more importantly, regular exercise does so much more than that — no matter the size of your waistline. It would take almost 10 medications to replicate all the benefits encapsulated in the “exercise pill.” That should be good motivation to help you get moving.

Related Information: Walking for Health

Comments:

  1. Tracie

    This information is very motivating! Knowing that I don’t have to be a super athlete in order to gain the effects of exercise relieved my workout pressure. After reading your blog I worked out five days this week. Just knowing that I didn’t have to engage in anything extreme got me out there. Once I started working out, I didn’t want to stop.
    Thank you!

  2. shake farid

    hi
    very nice post
    a row or a cycle etc.uses energy clarify, a motion, such as a step, rows or cycles per minute might not use any more energy than 150 though there might be and the more motions per minute results in using more energy per minute up to a meaning steps, other benefits to the higher intensity apart from using ,

    thanks

  3. Jo Melbourne

    I am afraid I am not convinced by the methodology used in the Current Biology report. In a workplace pedometer challenge I used to frequently come in “under” the totals recorded by some of my sedentary colleagues, even though 4000 of my “steps” would have been recorded running 5000 metres in 21 minutes. I think your article above is an important balance to the theoretical issues raised in the report. I would add the mental health benefits of exercise to be another issue for consideration. When asked by my patients about how much exercise to do I say “a little bit more than last week”, as a slow increase minimises the risk of injury, and avoids a threshold against which one may “fail” and give up.

  4. Renata Vianna

    I love the idea and it will help in my physical activity planning!

  5. Lucas Medeiros

    Excellent article.

    Here in Brazil, there are about 200 million inhabitants and 50% are overweighted; and we can observe an epidemic of chronic diseases.

    The health message could be changed by the ceiling effect perception – guilt of not being a marathon athlete… frugal physical activity and so many mind-body benefits.

    Enlightening! Thanks!

  6. Sims Wyeth

    When I was diagnosed with Type II diabetes about 10 months ago, I went overboard on the exercise, riding my bike like a mad man and exhausting myself. And I did this for a long time. I am a skinny diabetic, and I was skinny before I was diagnosed. I wish I’d known about the ceiling effect earlier. This is a great article, a comforting article, and one that will allow me to go for a nice long steady walk instead of hurling myself into exhaustion twice a day.

    Many thanks Beth.

  7. Zachary Cabon

    To clarify, a motion, such as a step, a row or a cycle (peddling), etc., uses energy … and the more motions per minute results in using more energy per minute … up to “a point” … meaning (arbitrarily) 300 steps, rows or cycles per minute might not use any more energy than 200 (though there might be other benefits to the higher intensity apart from using energy).

    Sounds like to use more energy, one would exercise moderately (e.g., 7 calories per minute or heart rate up to 119, depending on fitness level and age, etc.) for more minutes, rather than exercise intensely for less minutes … if the goal is simply to “use energy” (such as to decrease visceral and subcutaneous fat).

    If that is correct, then here’s to long (50 minutes or more), relatively slow (7 calories per minute, if somewhat fit) exercise sessions (probably while watching TV , writing emails, reading articles or listening to music).

    Please correct me if I misunderstood the information in this article.

  8. Timi

    Great inspiration to get moving! It’s nice to see a “prescription” with positive side effects.

  9. Michelle

    Wonderful article. I love how you describe the effects of exercise in a way that I can understand! And good to know that I don’t need to go all out to give myself a good workout. I wonder why the ceiling effect occurs?

  10. Robert Brooks

    A very important article about the positive effects of regular exercise on many aspects of our physical and emotional well-being.

  11. Laura D

    Love this article. Helps to know there are many reasons to exercise!

  12. Jon

    Great analysis and interpretation of the results! There is always more to the metabolic puzzle than we think. I love that this blog underscored the importance of physical activity, calorie expenditure aside. Bottom line, we need to eat better and move more!

  13. Kimberly Eason

    This is a great article especially for me when all I am able to do is walk through my neighborhood!

  14. George Touliatos

    Exercise boosts BMR either by cardio,or by resistance training.Nutrition could also boost BMR by consumption of protein,leading to thermogenesis,or eating often small meals.Physical activity has the benefit to built muscle tissue,apart from caloric expenditure.