How Is Exercise Related To A Healthy Gut?

It's widely accepted that diet impacts the health of our gut, that consuming a wide variety of fruits, vegetables, wholegrains, lean proteins and dairy, while limiting - refined or heavily processed products helps to maintain the balance of bacteria in our bellies. 

Other lifestyle factors also come into play; certain medications, stress, over consumption of alcohol can also throw out the balance. On the flipside, regular exercise has been shown to boost the population of good bacteria in the gut. 

Exercise & gut health - what does the science say?

While the research on the interplays between physical activity and gut health is still very much in its infancy, the overall picture points toward a positive relationship between regular exercise and a healthy gut, says Lulu Cook, RDN and Holistic Health Coach. In fact, it can actively (and positively) moderate the composition of gut microbiota.

One study comparing the gut health of the Irish National Rugby team compared to sedentary men found the elite athletes had healthier gut populations. While this sample involved subjects at the more extreme end of physical fitness and levels of daily exercise, a more recent study found similar results. 

Boffins from the European University of Madrid studied 40 women aged 18 –  40 years and compared subjects who exercised at least three hours a week with those that lived a more sedentary life. What they found was that regular and moderate exercise was associated with positive changes to the gut microbiota. 

"It appears that consistent, moderate exercise throughout life supports gut health through mechanisms such as increased microbial diversity and, preferential colonization by 'good' bacteria," Lulu says. 

Why exercise is good for your gut

There are a number of reasons why those that exercise regularly may enjoy better gut health

Lulu says those that exercise regularly are also more likely to observe a wider range of healthy lifestyle behaviours that are linked to good health – particularly consuming a healthy diet.

"On the flipside, those with a sedentary lifestyle often make poorer dietary choices, which we know is also linked to less healthy gut microbiota," says Lulu. 

This overall 'system' of poor exercise and diet choices can mean higher body fat percentages and lower muscle mass, which can be correlated with less healthful strains of gut bacteria. 

Regular exercise is also part of a digestive function that affects the health of our gut - defecation. "Much like consuming enough fibre and water, exercise stimulates the bowel and helps keep us 'regular' - this is an important part of maintaining intestinal microbial balance," Lulu says. 

That said, she notes the link between a healthy gut and exercise is a nuanced picture, meaning optimal levels of exercise are quite achievable - think 30 minutes of moderate activity per day (ideally accumulate 150 to 300 minutes of moderate intensity physical activity or 75 to 150 minutes of vigorous intensity physical activity each week) as per the National Guidelines for Physical Activity.