The Effect of Postbiotics Supplementation on Exercise-induced Oxidative Stress.

Changes in PC,Changes in malondialdehyde (MDA),Changes in reduced glutathione (GSH),Changes in oxidized glutathione (GSSG),Changes in GSH/GSSG ratio,Changes in catalase,Changes in total antioxidant capacity (TAC),Changes in uric acid,Changes in bilirubin,Changes in blood lactate,Changes in in delayed onset of muscle soreness (DOMS) in the knee flexors (KF) and extensors (KE) of both limbs,Changes in creatine kinase (CK),Changes in countermovement jump (CMJ) height,Changes in isokinetic strength of knee extensors (KE) and knee flexors (KF)

Scientific data on the effect of supplementation of postbiotics on exercise-induced oxidative
 stress are scarce. The main purpose of the research is to investigate the effect of
 postbiotics supplementation on exercise-induced oxidative stress and performance indicators
 after intense exercise. The study will be a cross-over, randomized, double-blind, controlled
 study that will be conducted in two cycles. Participants will be randomly assigned into one
 of the two trials: i) Postbiotics supplementation for 4 weeks, ii) Placebo supplementation
 for 4 weeks. Participants will then perform a 45-min treadmill running at (-15% slope, ~70%
 VO2max) followed by a time-trial (0% slope, ~95% VO2max) until exhaustion. Before, as well as
 24 h, 48 h and 72 h after the exercise, participants will undergo measurements of
 exercise-induced muscle damage (EIMD) [delayed onset of muscle soreness (DOMS), creatine
 kinase], blood redox status [total antioxidant capacity, catalase, protein carbonyls, reduced
 glutathione, oxidized glutathione], and isokinetic performance (knee-extensors and
 knee-flexors isometric, concentric, eccentric torque) evaluation. In addition, metabolism
 (lactic acid) will be assessed before and 4 min after exercise. Afterwards, the participants
 will receive the postbiotics supplement or the placebo for 4 weeks, and will repeat the
 exercise protocol and measurements of EIMD, blood redox status and performance indices at the
 same time-points. At the second cycle, the participants will repeat the above procedures
 under the remaining condition. Between conditions, there will be a 14-day washout period. The
 results of the research will provide important information for coaches and physically active
 individuals, regarding the effectiveness of postbiotics in alleviating oxidative stress and
 improving performance after intense exercise.