Exercise-induced Muscle Damage

This randomized parallel-group clinical trial will compare the acute effects of three different inter-set rest intervals during a single lower-limb flywheel resistance exercise session in untrained men. Participants will be randomly allocated to one of three groups: 1-minute, 2-minute, or 3-minute inter-set rest interval. The primary outcome will be the change in maximal voluntary isometric contraction of the knee extensors 48 hours after exercise. Secondary outcomes will include mechanical variables during the exercise session, countermovement jump performance, knee flexor maximal voluntary isometric contraction, muscle soreness, pressure pain threshold, range of motion, ultrasound-derived muscle thickness and echo intensity, perceived exertion, perceived discomfort, perceived recovery status, creatine kinase, and lactate dehydrogenase.

The purpose of this study is to evaluate how probiotic supplementation (PS) influences post-exercise recovery in healthy, physically active young adults. Researchers aim to determine if the Lactobacillus casei probiotic strain reduces symptoms of delayed onset muscle soreness (DOMS) based on perceived muscle soreness, pressure pain threshold, and power output following exercise induced muscle damage (EIMD).

In 2020, Dubois and Esculier proposed a paradigm shift in the acute management of musculoskeletal injuries, advocating for the transition from the traditional PRICE protocol- Protect, Rest, Ice, Compression, Elevation-to the more holistic PEACE \& LOVE framework. This updated model emphasizes Protection, Elevation, Avoiding anti-inflammatories, Compression, and Education, followed by Load, Optimism, Vascularization, and Exercise. Notably, the PEACE \& LOVE approach omits the use of ice, a decision that has sparked considerable debate. While the rationale centers on avoiding interference with the natural inflammatory and regenerative processes, this omission stands in contrast to a substantial body of animal research suggesting that cryotherapy can mitigate secondary tissue injury by reducing inflammation and metabolic activity. Despite its widespread clinical use, human studies have yet to provide conclusive evidence supporting or refuting the efficacy of cryotherapy in acute injury management, leaving clinicians to navigate between tradition, emerging evidence, and evolving philosophies of care. Even though it is important to consider natural inflammation for a better regenerative process, animal models have shown that the original injury can elicit oxidative stress, which will enhance cellular damage (secondary damage) and inflammation. Clinically, it is unknown if this secondary damage would increase functional impairment. Therefore, this proposal will determine if cryotherapy can decrease secondary damage, after exercise-induced muscle damage, and if this decrease is associated to lower inflammation, oxidative stress and functional impairments.

This is a prospective, randomized, placebo controlled, double-blind study to assess the effects of a postbiotic blend on exercise induced oxidative stress markers and exercise performance in healthy adult.