Diet & Nutrition

7 Surprising Ways Your Gut Health Affects Your Fitness

7 Surprising Ways Your Gut Health Affects Your Fitness

It's been an amazing few decades for health and fitness research. From a more accurate understanding of how sugar and fat affect the body to new insights into the underrated health benefits of exercise for your mind and the much needed shift towards body positivity in the fitness world, we're living through an exciting period of research and development into what keeps us feeling good and looking great.

One of the most important leaps in recent research, though, is the effects that your gut bacteria have on your physical fitness. While the scientific community has been abuzz for a while about how your gut microbiome is the foundation of your overall health, research into its role in fitness is relatively new...but the findings are absolutely fascinating.

The Gut Microbiome: Your Secret Weapon for Leveling Up Your Fitness

When you think of improving your fitness, what's the first thing that comes to mind? You’re probably envisioning something along the lines of a workout program, change in diet, or gym membership—chances are, your gut bacteria wouldn't even cross your mind in a fitness context.

But the good guys in your gut do a lot more than you might think to keep you healthy and fit. In fact, they can be just as important for your workout as any other part of your fitness plan, if not more so. Why? Because they can support your efforts in terms of everything from weight management to workout stamina.

Here are seven ways your gut bacteria help to support your fitness:

1. Support Healthy Weight Management

Did you know that researchers can more accurately predict whether someone is overweight or thin from their bacterial makeup than from their genes?1 It’s because the way your body holds onto or sheds weight depends on way more than what you eat or how much you move.

In fact, your gut bacteria can dramatically impact your weight management efforts by influencing how your body absorbs nutrients, creating the hormones associated with feeling full, and helping to keep blood sugar levels in a normal range. While bacterial balance isn’t the end all and be all of weight management––eating healthy, nutrient dense foods and moving regularly are of course important for a healthy lifestyle––it’s an often-overlooked clue to your weight management efforts. Support your bacterial balance, and you might find it much easier to maintain a healthy weight, which can make it that much easier to reach your fitness goals.

2. Encourage the Production of SCFAs

Short-chain fatty acids (SCFAs) are substances like butyrate, propionate, and acetate that your bacterial good guys produce when they digest dietary fiber. SCFAs are important for many different processes in the body—including discouraging temporary inflammation, keeping your gut barrier strong, and helping your body maintain bacterial balance by making it harder for unwanted bacteria to proliferate—but what's particularly interesting in the context of fitness is their role in producing energy.

SCFAs make up about 10% of your caloric requirements in a day, and they're used in various other processes that create energy and support a healthy weight.2 Of course, they can only do this when they're actually present in your body, which is where the benefits of probiotics and prebiotics come in. Friendly flora are like SCFA factories; give them enough prebiotic fiber and they'll not only thrive on the nourishment––they'll ferment some of those fibers into SCFAs.

3. Support Nutrient Absorption

On the surface, nutrition seems fairly simple—eat healthy, nutrient dense foods, and you should be able to achieve your fitness goals. It’s actually not that straightforward, though. You see, you could be eating the healthiest food in the world, but still not getting the nutrition you need if your body isn’t able to absorb it and use it properly. And since nutrition and fitness go hand in hand––with the nutrients you absorb forming the building blocks for the processes that produce the energy required for an effective workout––it’s worth paying attention to the things that can affect your nutrient absorption, including your gut microbiome.

The balance of your gut microbiome is a huge determiner of how well your body is able to break down, absorb, and use nutrients, with certain beneficial bacteria helping out with the digestion process and maintaining your intestinal wall, where the majority of nutrient absorption occurs.3 With the right mix of gut bacteria, you can help keep your intestinal wall structurally sound enough to absorb all that nutritional goodness you’re eating, which both gives your body the raw materials it needs to produce energy and repair itself after a workout and promotes a feeling of satiation, so you feel full and satisfied after eating, and are less likely to overeat.

4. Keep Your Immune Function Going Strong

It’s the curse of the dedicated fitness enthusiast: getting derailed by a couple of off days just when you’re about to reach a new level with your workout. If you find that you regularly feel under the weather after an intense period of training, you’re not alone. In fact, people who participate in heavy training often tend to be more prone to upper respiratory issues because of the short-term effects intense exercise has on the immune system.4

One of the best things you can do to avoid this is to give your gut microbiome a little extra support. Why? Because the majority of your immune function stems from your gut. (In fact, about 80% of your immune cells live in your gastrointestinal tract.) By making sure you have enough beneficial bacteria to keep your gut healthy, you can support your immune function, work to mitigate any potential unwanted effects from intense training, and even lend some support to the other significant site of immune function, your mouth, ear, nose, and throat microbiomes. The result? More healthy days and fewer interruptions in training so you can keep consistently working on your fitness.

5. Support Post-Workout Recovery

After you work out, your body immediately goes to work repairing itself, rehydrating, getting rid of the lactic acid that can build up in your muscles, rebuilding muscle tissue, and balancing out your blood sugar so you don’t get the “lag effect” of a post-exercise crash.5 Your gut bacteria are essential components of the recovery process, helping to convert lactate from lactic acid bacteria into butyrate, helping to ease soreness, fermenting prebiotics into health-promoting SCFAs, keeping your blood sugar levels in the normal range, and supporting nutrient absorption so your body has the materials it needs to rebuild itself.6

Interestingly, certain types of gut bacteria can be linked to better recovery from specific types of exercise. Studies show that the gut microbiomes of elite athletes actually adapt in ways that help them perform better, in many cases because they support better recovery in between workouts.

For instance, research shows that cyclists tend to have dramatically higher proportions of bacteria that help with amino acid synthesis, which enables their bodies to recover after rigorous training.7 Similarly, marathon runners often harbor higher concentrations of beneficial bacteria that help with metabolism, muscle maintenance, and the breakdown of lactic acid.8 While you might not be a professional cyclist or training to run a marathon, supporting your gut microbiome with strains that specifically help with athletic performance and recovery can help you stay at the top of your game, too!

6. Maintain Bone and Joint Health

Exercise can be tough on bones and joints. While (thankfully) the prevailing trend in fitness is to listen to your body and not push yourself to the point of pain, your body can still take a beating from a strenuous workout.

Over time, this can translate into negative effects on your bones and joints, making it harder for you to move the way you want to. You can do a lot to keep performing at a high level with a good flexibility practice and responsible warm ups and cool downs, but it’s also important to get your gut bacteria in on the game, since they can help calm discourage conditions that can leave you achy, produce enzymes and nutrients that support bone health, and even help manage the effects of oxidation that can break down your bone and joint cells.9

7. Stay Energized for Endurance

Your stamina, energy, and endurance stem from a lot of things, including your genetics, how much and how often you exercise, and how well nourished you are, but your gut microbiome also plays a part. Studies show that athletes who supplement with probiotics have dramatically better energy levels and endurance than those who don’t, even when exercising in adverse conditions like extreme heat and humidity.10

This comes down to the effect those beneficial bacteria have on the hormones that keep you feeling energetic, how well your body can build up muscle tissue, and your immune function. Your microbial good guys even get your mind in on the game by supporting mental clarity and focus, which are, as any athlete knows, at least half the battle when it comes to making it through a really tough workout.11

And don't forget about prebiotics! These oh-so-important fibers have benefits even beyond their role in keeping your microbiome balanced, including supporting the muscles involved in respiration, with research indicating that supplementing with prebiotics can reduce the levels of biomarkers associated with temporary inflammation that can close the airways and make exercise difficult.12

How Exercise Supports Your Gut Health

So it's clear that having a healthy gut microbiome can support your exercise efforts...but what's really impressive is that this relationship actually goes both ways. Just as balancing your gut microbiome can help your workout, working out also helps support a healthy gut microbiome.

This happens in a few ways. Research shows that exercising regularly not only increases the number of beneficial bacteria in your microbiome (including those that produce SCFAs); it also increases the diversity of species found there, which typically translates into better overall health.

What's more, these results happen quickly––studies show that just a few weeks of consistent exercise can noticeably change the composition of your gut microbiome for the better.13 Additionally, exercising tends to lower your stress levels, and lower stress is closely connected with a healthier gut microbiome, as the physical changes that accompany stress in the body create conditions that favor the growth of unwanted bacteria.

In a nutshell: exercise benefits your microbiome so that your microbiome can keep benefiting your exercise.

Three Simple Ways to Support Your Microbes

So what can you do to support your microbiome so it can in turn support your fitness efforts? A lot, actually! You've got loads of options when it comes to maintaining your microbial health, but it's a good idea to make sure you've got the basics down first. So make sure that you're eating whole foods high in plant-based fibers that are ideally seasonal, local, and organic, since your diet has a huge impact on the balance of your microbiome. (This goes for fitness supplements too, by the way––often the powders, bars, and drinks marketed as fitness aids are full of sugar and synthetic ingredients that can wreak havoc on your gut bugs.)

Similarly, avoid other things that can deplete your good guys, like exposure to antibiotics in food or medication, as well as antimicrobial cleansers and soaps. Your skin is closely connected to your gut, and many common household and hygiene products (especially those full of harsh chemicals) can disrupt the balance of your skin microbiome, and by extension, your gut.

Finally, consider supporting your microbiome with a premium probiotic like PRO-Compete, which contains strains specifically selected to support performance in athletes, including L. plantarum 6595. Our modern Western lifestyle makes it hard to maintain microbial health even if you are really conscious about what you're putting in and on your body, so it's a good idea to give your gut a little extra love by proactively replenishing it with beneficial bacteria. (And don't forget the prebiotic powder––you've got to give those good guys something to eat!)

Fitness is such an important component of a healthy, happy life: it can be self-care, entertainment, personal fulfillment, and the foundation of good health for years to come all rolled into one. And just as important as choosing the right equipment for your workout—from supportive running shoes to the perfect yoga mat—is giving yourself the right internal equipment to perform at your best. With extra support for your energy, stamina, and endurance from your microbes, you'll be well equipped to take your workout to the next level!


1. Walters, W.A., Xu, Z., Knight, R. (2014). Meta-analyses of Human Gut Microbes Associated with Obesity and IBD. FEBS Letters, 588(22), 4223-4233. doi: 10.1016/j.febslet.2014.09.039

2. Morrison, D.J., Preston, T. (2016). Formation of Short Chain Fatty Acids by the Gut Microbiota and Their Impact on Human Metabolism. Gut Microbes, 7(3): 189–200. doi: 10.1080/19490976.2015.1134082

3. Rao, R. K., & Samak, G. (2013). Protection and Restitution of Gut Barrier by Probiotics: Nutritional and Clinical Implications. Current Nutrition & Food Science, 9(2), 99-107.

4. Mackinnon, L.T. (1997). PAKs Supplement Improves Immune Status and Body Composition but not Muscle Strength in Resistance Trained Individuals. International Journal of Sports Medicine, 18(Suppl 1) S62-8. doi: 10.1055/s-2007-972701

5. Simon, M., Strassburger, K., Nowotny, B., Kolb, H., Nowotny, P., Burkart, V., . . . Roden, M. (2015). Intake of Lactobacillus reuteri Improves Incretin and Insulin Secretion in Glucose-Tolerant Humans: A Proof of Concept. Diabetes Care,38(10), 1827-1834. doi:10.2337/dc14-2690

6. Monda, V., Villano, I., Messina, A., Valenzano, A., Esposito, T. ... Messina, G. (2017). Exercise Modifies the Gut Microbiota with Positive Health Effects. Oxidative Medicine and Cellular Longevity. doi: 10.1155/2017/3831972

7. Petersen, L.M., Bautista, E.J.,Nguyen, H., Hanson, B.M. . . . Weinstock, G.M. (2017). Community Characteristics of the Gut Microbiomes of Competitive Cyclists. Microbiome 5(98). doi: 10.1186/s40168-017-0320-4

8. Barton, W.B., Penney, N.C., Cronin, O., Garcia-Perez, I. . . . O'Sullivan, O. (2017). The Microbiome of Professional Athletes Differs from that of more Sedentary Subjects in Composition and Particularly at the Functional Metabolic Level. Gut Microbiota 0,1–9. doi:10.1136/gutjnl-2016-313627.

9. Amdekar, S., Kumar, A., Sharma, P., Singh, R., & Singh, V. (2012). Lactobacillus protected bone damage and maintained the antioxidant status of liver and kidney homogenates in female wistar rats. Molecular and Cellular Biochemistry, 368(1-2), 155-165.

10. Shing, C. M., Peake, J. M., Lim, C. L., Briskey, D., Walsh, N. P., Fortes, M. B., . . . Vitetta, L. (2013). Effects of Probiotics Supplementation on Gastrointestinal Permeability, Inflammation and Exercise Performance in the Heat. European Journal of Applied Physiology, 114(1), 93-103.

11. Zhou, L. and Foster, J.A. (2015). Psychobiotics and the Gut–Brain Axis: in the Pursuit of Happiness. Neuropsychiatric Disease and Treatment, 16(11), 15-23. doi: 10.2147/NDT.S61997

12. Williams, N.C., Johnson, M.A., Shaw, D.E. . . . Hunter, K.A. (2016). A prebiotic Galactooligosaccharide Mixture Reduces Severity of Hyperpnoea-induced Bronchoconstriction and Markers of Airway Inflammation. British Journal of Nutrition 116(5). pp. 798-804. doi: 10.1017/S0007114516002762.

13. Chen, Y., Wei, L., Chiu, Y., Hsu, Y., Tsai, T., Wang, M., & Huang, C. (2016). Lactobacillus plantarum TWK10 Supplementation Improves Exercise Performance and Increases Muscle Mass in Mice. Nutrients, 8(4), 205.


Rachel Allen is a writer at Hyperbiotics who's absolutely obsessed with learning about how our bodies work. She's fascinated by the latest research on bacteria and the role they play in health, and loves to help others learn about how probiotics can help the body get back in balance. For more ideas on how you can benefit from the power of probiotics and live healthier days, be sure to subscribe to our newsletter. To learn more about how a healthy microbiome can enrich your life, subscribe to our newsletter.