Inclusion and exclusion criteria
SARS-COV-2 INFECTION
All the players were members of the same club and performed identical training loads. Only participants who completed at least 85% of training sessions and had no SARS-CoV-2 infection were included in the study. Moreover, players who used a diet other than the preferred diet of the club, including supplementation of vitamin D, and minerals (especially Calcium and Phosphorus)calcium and phosphorus), or made use of a solarium, used anti-solar filters, and trained outside without the allowance of the club trainers were excluded from the research. During a one1-year training season, a total of 16 players did not meet the inclusion criteria (6six players were injured, another 4four missed more than 15% of training sessions, and 6six players were excluded due to illness). Finally, 24 players were included in the analysis of the results.