I’ve been talking about the importance of exercise and gut health for quite a while now.
When I first read a study back in 2010 on “Shinrin-yoku” (or forest-bathing), many questions I had about why I felt so good after a hike in nature or even a swim in the sea became clearer: I was breathing in organic compounds called phytoncides. These essential oils released from plants in nature have been shown to increase the efficacy of our gut by helping fight off harmful microorganisms.
Now, we have definitive scientific evidence that exercise can help change the microbes in your gut. I’m excited about this and here’s why.
Researchers around the world have been looking into the effects of exercise on the composition of our microbiome and have finally found something really worth talking about: workout sessions and movement throughout the day help increase the concentration of short chain fatty acids (like butyrate) within our guts, which ultimately improves our overall health.
This science news sends a powerful message about our gut microbiome.
To hone in on the powers of exercise, researchers at the Department of Kinesiology and Community Health at the University of Illinois initially looked at specially bred mice that were germ free (the proverbial “clean slate” in science).
They separated the mice into two camps: those that used an exercise wheel for six weeks and those that played the role of couch potato. After the six weeks were up, they transplanted bacteria from the fit mice into the sedentary ones just to see what would happen.
The results were stunning. Sedentary mice that received the transplant suddenly had higher levels of butyrate and a corresponding reduction in inflammation, as well as favorable alterations to their body mass. They also became more resistant to IBS and ulcerative colitis. Suddenly these whiskered couch potatoes had the digestion-based benefits of exercise, without ever having moved a muscle!
The real takeaway here is pretty powerful: exercising altered the guts of the first set of mice so profoundly, that the evidence could actually be harvested and transplanted–and the benefits could be transplanted too.
But what do these results obtained using mice have to do with humans? Simple: by using such a controlled set of ‘participants’ researchers are able to focus in on what was really working. Once a key factor is isolated, it can be used in other studies with other subjects, like our fellow humans.
And that’s exactly what Illinois’s Department of Kinesiology did. Once promising results were found in mice, they wanted to determine if similar results could be cultivated in humans (sans transplantation).
Informed by their prior study, they were able to design the human component in a way that isolated exercise-induced changes from other potential factors (like antibiotic use) that might affect their subjects’ responses.
Once again, participants exercised for 6 weeks, and at the end of their trial their GI composition was determined. It turns out that exercise increased the concentration of short chain fatty acids like butyrate in humans too, but there was a twist: that positive increase in concentration was contingent on keeping up the exercise regimen. Once the participants reverted to their sedentary lifestyles their microbiome make-up reverted as well.
The takeaway from these two studies is fairly profound. It’s best summarized by Professor Jeffrey Woods, one of the researchers: “These are the first studies to show that exercise can have an effect on your gut independent of diet or other factors.”
The Power of Butyrate: Gut Buster Galore
For those not familiar with the power of short chain fatty acids like butyrate, it may not be apparent why this kind of study matters so much. Here’s are a couple of butyrate’s potential attributes:
First and foremost, it has the ability to suppress the appetite and therefore decrease overall food intake in humans and animals alike. Appetite suppression is helpful in putting the kibosh on overeating but it also reduces high insulin levels, reduces triglyceride count (which can lead to artery hardening and CVD), and prevents fatty liver disease.
For those of you hoping to lose weight or remain lean, butyrate also promotes the use of fat as fuel and the activation of brown fat–which increases calorie expenditure to keep you warm.
Clearly butyrate is a potential powerhouse acid you certainly want in your proverbial corner, and in your gut.
Bust a Move for Your Gut
So if you’re looking to optimize your microbiome, increase the concentration of those wonderful short chain fatty acids in your GI tract, and ‘bust that gut’ in more ways than one, you know what to do: get out there and move!