Acute and Long-Term Variations in Variables Related to Redox, Inflammation and Hormonal Status in Male Football Players: A Systematic Review and Recommendations

Introduction: The present study aimed to review the acute and long-term variations in variables related to redox, inflammation and hormonal status in male footballers. Materials and methods: A PRISMA-compliant systematic review was conducted. The entire content of PubMed, Scopus and Science Direct were systematically searched until May 2022. Studies with outcomes including: (1) adult male football players, (2) a redox and/or an inflammatory and/or a hormonal marker after a training period, and (3) variables measured in blood/saliva. Results: Thirty-four studies met the inclusion criteria for the qualitative synthesis. Fourteen studies on redox status, 16 on inflammation/muscle damage and 20 on hormonal variations. Only 4 studies incorporated markers related to all 3 statuses, while 8 studies looked at a combination of 2. Studies around redox homeostasis found several markers to fluctuate with MDA, TBARS, protein carbonyls, GSSG, GPx, CAT, and uric acid increasing immediately after a game. Hormonal markers, such as testosterone in blood, revealed no significant change after training. Some found T to increase post-exercise, and some a decrease. Cortisol increased in both short- and long monitoring periods. Markers associated with inflammation and muscle damage found creatine kinase elevated immediately post-game and over extended periods. LDH, C-RP, and IL-6 were also higher post-match. Discussion: Exposure to short or long-term participation in football training and competitions could significantly affect footballers' redox, inflammation and hormonal status. However, greater consistency across studies is required to ascertain the implications of structured training regimens on measured variables. Selecting the most relevant protocol/ conditions and biochemical markers, including the collection time and the type of specimen, must be considered.