Trending Topics

Exercise, Why Not?

Thomas M. Meyer, MD
What you never learned about exercise in school. Dr. Meyer explains how exercise will help your patients live a longer life, both physically and mentally – but, at the same time, it won’t necessarily do what they want it to do.
8/18/2021
Internal Medicine
GIBLIB

Everything is driven by the famous krebs cycle that basically takes sugar and fatty acids and burns them and produces CO2. But protein is actually not a significant energy source. When we exercise, we engage depending on our exercise.

The limit on our exercise capacity is not our respiratory system, but our cardiovascular function. Each time an athlete pumps away at 40 beats per minute, they have a higher stroke volume than an untrained person.

Nevertheless, only about a quarter of the calories we consume are converted into muscular energy. The rest goes into fatty tissue and heat. So three quarters is wasted.


BENEFITS OF EXERCISE ON: YOUR MIND

Exercise has significant effects on the central nervous system. A study of more than 130 individuals, between age 20 and 67, showed that exercising four times a week improves cognitive function. When the MRI scanned them, the thickness of the cortex actually increased.

So there's a physical, anatomical change to the brain with exercise. But the cognitive decline in an older person was not really slowed by moderate exercise. The benefit of exercise on cognition is only manifested when the brain still has some plasticity.


CONCUSSIONS

We all recommend after a concussion to take it easy, rest, and do no activity. But in a study with more than 100 adolescents who suffered a concussion, it was shown that if those individuals started to exercise within 10 days of their concussion, they actually had a significantly faster resolution of concussion symptoms, which is a bit surprising and somewhat contrary.


THE HIPPOCAMPUS

In several animal models, as well as human studies, it was found that exercise changes the production of neurotrophic hormones and changes brain structure, especially the hippocampal structure. In patients with Alzheimer's disease and declining memory, exercise reduced the speed of hippocampal atrophy.

But unfortunately, cognitive function, testing, and declining memory did not really change significantly. Maybe longer-term studies will have a more positive result. Nevertheless, it was interesting to see that exercise actually changes how the brain remodels. Maybe it’s better to exercise than take whatever medications.


YOUR MOOD

Exercise, of course, also improves mood. It was found in a big meta analysis of 33 studies that exercise significantly reduces depressive symptoms.

They also looked into the question, is more exercise better? And interestingly, the findings showed that the amount and intensity of exercise were not directly associated with improvement in depression. Basically, exercising in a very intense fashion does not have a proportional effect on the rate of improvement.


YOUR LIFE

Metabolic exercise is well known from our diabetes care. Now, the big question: do we live longer because we exercise? Again, that's a question that is not easily answered. Exercise does protect from various Carterville cardiovascular risk factors and has anti-inflammatory effects. And it does improve cardiovascular function.

Of course, the amount of exercise and our age when we exercise seem to be important factors in gauging the benefit or risk of exercise. There's only so much we can burn through exercise before our metabolism will start regulating in order to preserve energy.

And that makes total sense from an evolutionary standpoint because, in order to survive outside of civilization, we had to be very energy efficient. And the bottom line is that you can't outrun a bad diet.


CONCLUSION

If my patient asked me about it, I would say that the purpose of exercise is to live. Exercise regularly, but obsessing over a certain, extreme goal might be detrimental.


To learn more about the effects of exercising, click here: https://watch.giblib.com/video/5414



Watch Video

EARN CME

Watch, learn, and earn unlimited AMA PRA Category 1 Credit(s)™. Our continuing medical education process is simple, fast and efficient. Get access to thousands of accredited medical lectures, surgical videos, and courses. Clinician-learners complete an assessment test and can download CME certificates instantly.

ABOUT GIBLIB

GIBLIB is the premier streaming service with a vast catalog of unrivaled continuing medical education content covering surgical videos, medical lectures, courses, and transcripts. Learn from the world’s best doctors, from the top leading institutions, including Mayo Clinic, UCSF, Cedars-Sinai, Keck Medicine of USC, and many more.

View recent posts

Trending Topics
Weight Gain in Midlife Women: What to Do About the Middle Age Spread?
One of the most common questions women ask their healthcare providers is “why am I gaining weight despite doing everything the same/right?” Kapoor, MBBS explains causes and treatment options.
Medical Lectures
The Importance of Compassion: Compassion in the Hospital Setting
In a John Hopkins study, 56% of physicians surveyed said they don't have time for compassion – but that is what your patients need the most. Learn how compassion betters hospital care
COVID-19 Updates
Breaking down COVID-19 vaccine booster approvals
In this Mayo Clinic Q&A podcast, Dr. Poland talks about the approval process for COVID-19 vaccine boosters, including for the Moderna and J&J COVID-19 vaccines, as well as the possibility of emergency use approval for children, down to age 5, before the end of October.
Start 4-day FREE trial and get unlimited access to surgical videos, medical lectures, and courses.
Get Started