“We found that L-PS23 or HK-PS23 supplementation for six weeks prevented strength loss after muscle damage and improved blood muscle damage and inflammatory markers, with protective, accelerated recovery and anti-fatigue benefits,” wrote researchers from the Graduate Institute of Sports Science at the National Taiwan Sport University (NTSU).
Published in the Nutrients journal, the study was supported by the NTSU University-Industry Cooperation Fund.
The gut-muscle axis
Noting that sports nutrition has largely focused on supplements with antioxidant or anti-inflammatory properties like omega-3s, curcumin and polyphenols, the study authors point to a growing body of research tying probiotics to exercise recovery.
“In recent years, as the role of the gut-muscle axis has received increasing attention, more and more studies have explored the relationship between gut microbes and exercise performance,” they wrote.
“Past research has shown that probiotics can improve inflammation and oxidative stress, as well as improve exercise performance and antifatigue. However, further research is needed to confirm the recovery benefits for muscle damage.”
To explore these benefits, the study evaluated the effects of both live and heat-killed PS23 based on findings that “that non-viable bacteria and bacterial fractions could pass through the mucus and stimulate epithelial cells more efficiently than live bacteria.” Heat-killed bacteria or their fractions have been shown to have key beneficial effects similar to those of live probiotics, with the added value of an improved safety profile and shelf life without refrigeration.
Previous studies in mice have shown that PS23 (isolated by Taipei-based Bened Biomedical Co. and sold under the Vigorbiotics brand) alleviates skeletal muscle atrophy, delays the progression of cognitive decline and reverses induced depressive behaviors. This is the first study, the researchers say, that evaluates the effect of the strain on athletic performance or slowing muscle damage in young adults.
Study details
The double-blind trial recruited a total of 78 male and 36 female university students between the ages of 20 and 40 years. Participants were then randomly assigned to one of three groups that received either two capsules a day of a microcrystalline cellulose placebo, live PS23 bacteria or heat-killed PS23 bacteria. The gender ratio of 26 males to 12 females was standardized across groups.
Following a six-week supplementation period, subjects completed 100 maximal vertical jumps (commonly used to evaluate athletes’ speed, maximal strength, explosive power and anaerobic performance) to bring about exercise-induced muscle damage (EIMD). Body composition, basal blood biochemical parameters and exercise performance were measured before supplementation and prior to the exercise experiment. Biomarkers of muscle damage and indicators of inflammatory and oxidative damage were assessed at 3, 24 and 48 hours after EIMD.
“The results show that both L-PS23 and HK-PS23 supplementation significantly slowed the loss of muscle strength after muscle injury, and they significantly reduced the production of markers of muscle damage and inflammation,” the study concluded. Benefits were more pronounced in the heat-killed PS23 test group.
The researchers call for further human trials to compare the recovery effect of PS23 on muscle injury in men and women, as well as focused in vitro or animal experiments and gut bacteria analysis to explore how PS23 aids muscle cell activity or regeneration for recovery.
Source: Nutrients 2022, 14(21), 4563
doi: 10.3390/nu14214563
“Live and Heat-Killed Probiotic Lactobacillus paracasei PS23 Accelerated the Improvement and Recovery of Strength and Damage Biomarkers after Exercise-Induced Muscle Damage”
Authors: Mon-Chien Lee et al.