So what exactly are probiotics, and how can they help you sculpt a world class physique?
The Good, The Bad And The Germy
The simplest way to explain probiotics would be to simply say that they are (mainly) bacteria. But don’t be alarmed- like everything else in life, there are good and bad sides to everything, bacteria included.
Your body is actually habitat to an array of bacterial species, some of which are bad and look for opportunities to bring about ill-health, and others which are beneficial, such as the probiotics.
The vast majority of your body’s probiotic bacteria reside in your intestinal tract, in both the small and large aspects of the intestines. A small amount of probiotic organisms are also fungi, though these are not often encountered in supplemental form.
The battle between these good bacteria- the probiotics, and the pathogenic bacteria residing in your body is a daily struggle, but one which you can help out with by fortifying your body’s natural probiotic colony numbers via supplementation.
Wondering which probiotic strains you should be focusing on? Let’s check them out now.
Commonly known as just acidophilus, this strain is by far the most common and frequently discussed probiotic. Arguably, this is the supplement that started all the interest in probiotic consumption as a way to bolster digestive, and in turn- overall health.
There are many probiotics classified as being Lactobacilli (plural for Lactobacillus), but acidophilus possess unique strengths. For instance, a study published in the Journal British Association of Sport and Medicine in 2006 found that administration of acidophilus helped to correct immune deficits characteristic of athletes with a chronically fatigued/ over trained status[i].
Of course, there are also many other benefits of acidophilus that are shared by other probiotic strains.
Arguably the second most common probiotic out there, the human body actually starts out with a huge proportion of this species; around 80% at birth, but which decreases to between 2 and 14% during adulthood.
But what makes this probiotic different from acidophilus, or any other for that matter? One of its primary selling points would have to be its ability to enhance immune function[ii], meaning that you get ill less frequently.
Less sick days means fewer missed workouts, and even if do did get sick, the illness is usually self-limiting and brief.
Another member of the lactobacillus family, this is where things start getting very interesting (no offence to you guys that came before!). In particular, is the way that that it is able to make a dent (literally) on your waistline, as it has been revealed that it possesses anti-obesogenic properties[iii], reducing inflammation, blood glucose dysfunction[iv] that contributes to weight gain, and supporting healthy liver function which can impair effective metabolism of fat.
Another study, published in the British Journal of Nutrition in 2014[v] found that supplementation with a probiotic rich in Lactobacillus rhamnosus was actually able to initiate weight loss in obese men and women, though its effect was more consistent across women who were able to lose weight and maintain the weight loss.
Leptin levels were also reduced, which is good in the case of obese subjects as leptin resistance is most frequent in this class.
It’s the moment you’ve been waiting for, we finally arrive at the probiotic that can directly help influence the muscle gains you make from your hard work in the gym. Although not one of the bigger, well-known probiotics, Lactobacillus Reuteri is likely to be of greatest interest to strength athletes, especially when combined with other probiotics.
But how exactly does this strain help with your muscle building goals? One primary way – cortisol modulation. You see, cortisol and testosterone are not friends[vi], but rather exert actions that are on opposite ends of the spectrum when it comes to muscle homeostasis. Cortisol is concerned with breaking down of tissue (catabolism), while testosterone favours the accrual of new tissue (anabolism).
These two hormones also share what is known as a negatively inverse relationship, in that as one goes up, levels of the other goes down. Lactobacillus Reuteri is able to reduce cortisol levels, having the effect of indirectly causing testosterone to flourish.
While most of the studies concerning Lactobacillus Reuteri have been conducted on rodents, there is anecdotal evidence that many of its benefits on male health holds true. For instance, in rodents, a study conducted by MIT in 2014 found the following after adding Lactobacillus Reuteri to the drinking water of the rats, they had:
- Larger testicle size when compared with control
- Higher luteinizing hormone levels, in turn signalling for an increased production of testosterone
- Improved sperm count and mobility
- Reduced effect of age related testicular atrophy in mice[vii], which coincides with reduction in natural testosterone production
Another study, this time conducted in men and published in the Journal of clinical endocrinology and metabolism in 2013 found that daily supplementation of Lactobacillus Reuteri over the course of 13 weeks resulted in an average increase in serum vitamin D levels by 25%[viii].
This is noteworthy because in men, higher vitamin D levels is positively associated with greater testosterone synthesis.
Universal Benefits Of Probiotics
Beside these specific sport centric benefits of probiotics, there are other noteworthy ones such as improved digestive health, reduced inflammatory burden and risk of intestinal cancers, decreased likelihood of experiencing autoimmune conditions affecting the digestive tract, lowered risk of developing gastric ulcers owing to the bacteria H. pylori as well as improved nutrient status and psychological well-being.
Probiotics help demonstrate that your gut and brain are inextricably linked, by virtue of the vagus nerve – the largest nerve in the human body. This is why you experience a nervous gut when you are anxious, and how improving the health of your digestive tract can lend itself to enhanced brain function.
One important note to clarify is the fact that not all probiotics require refrigeration prior to being opened. This is because differences in manufacturing, such as the use of a freeze-drying technique, can add stability to products until they are exposed to room temperature and air after tearing the seal.
It is also important to choose a product that guarantees a certain number of probiotics per bottle/serving, represented as CFU, or colony forming units.
As for the best probiotics to choose, a lot depends on your current diet, and what you expect them to do. Acidophilus and bifidum are great entry-level probiotics, being the most common in your intestines, but if you’re looking for more sport specific benefits, reuteri and rhamnosus may be better picks.
The world of probiotics is large – we merely touched the surface of the many species that exist. The important thing is to ensure that you support the healthy colonies residing in your gut- don’t wait for a problem to make an intervention.
[i] Clancy RL, Gleeson M, Cox A, et al. Reversal in fatigued athletes of a defect in interferon gamma secretion after administration of Lactobacillus acidophilus. Br J Sports Med. 2006;40(4):351–354. doi:10.1136/bjsm.2005.024364
[ii] Langkamp-Henken B, Rowe CC, Ford AL, Christman MC, Nieves C Jr, Khouri L,Specht GJ, Girard SA, Spaiser SJ, Dahl WJ. Bifidobacterium bifidum R0071 results in a greater proportion of healthy days and a lower percentage of academicallystressed students reporting a day of cold/flu: a randomised, double-blind,placebo-controlled study. Br J Nutr. 2015 Feb 14;113(3):426-34. doi:10.1017/S0007114514003997. Epub 2015 Jan 21. PubMed PMID: 5604727.
[iii] Pothuraju R, Sharma RK, Chagalamarri J, Kavadi PK, Jangra S. Influence of milk fermented with Lactobacillus rhamnosus NCDC 17 alone and in combination with herbal ingredients on diet induced adiposity and related gene expression in C57BL/6J mice. Food Funct. 2015 Nov;6(11):3576-84. doi: 10.1039/c5fo00781j. Epub 2015 Sep 1. PubMed PMID: 26327356.
[iv] Park KY, Kim B, Hyun CK. Lactobacillus rhamnosus GG Reverses Insulin Resistance but Does Not Block Its Onset in Diet-Induced Obese Mice. J Microbiol Biotechnol. 2015 May;25(5):753-7. PubMed PMID: 25433553.
[v] Sanchez M, Darimont C, Drapeau V, Emady-Azar S, Lepage M, Rezzonico E, Ngom-Bru C, Berger B, Philippe L, Ammon-Zuffrey C, Leone P, Chevrier G, St-Amand E, Marette A, Doré J, Tremblay A. Effect of Lactobacillus rhamnosus CGMCC1.3724 supplementation on weight loss and maintenance in obese men and women. Br J Nutr.
2014 Apr 28;111(8):1507-19. doi: 10.1017/S0007114513003875. Epub 2013 Dec 3. PubMed PMID: 24299712.
[vi] Cumming DC, Quigley ME, Yen SS. Acute suppression of circulating testosterone levels by cortisol in men. J Clin Endocrinol Metab. 1983 Sep;57(3):671-3. PubMed PMID: 6348068.
[vii] Poutahidis T, Springer A, Levkovich T, Qi P, Varian BJ, Lakritz JR, Ibrahim YM, Chatzigiagkos A, Alm EJ, Erdman SE. Probiotic microbes sustain youthful serum testosterone levels and testicular size in aging mice. PLoS One. 2014 Jan
2;9(1):e84877. doi: 10.1371/journal.pone.0084877. eCollection 2014. PubMed PMID: 24392159; PubMed Central PMCID: PMC3879365
[viii] Jones ML, Martoni CJ, Prakash S. Oral supplementation with probiotic L. reuteri NCIMB 30242 increases mean circulating 25-hydroxyvitamin D: a post hoc analysis of a randomized controlled trial. J Clin Endocrinol Metab. 2013 Jul;98(7):2944-51. doi: 10.1210/jc.2012-4262. Epub 2013 Apr 22. PubMed PMID: 23609838