Mood states, gastrointestinal symptoms, and renal biomarkers in Brazilian bodybuilders across different competition preparation phases

This study aimed to examine variations in mood states, gastrointestinal symptoms, and kidney function in non-drug-free amateur bodybuilders across four peri-competition timepoints: 7 days before competition, competition day, 7 days after competition, and 14 days post-competition. The study was characterized as an exploratory longitudinal study with repeated measures. Nine amateur bodybuilders (median age: 30 years) participated in the study. Athletes were assessed at four moments using validated mood and gastrointestinal symptom scales, anthropometric measurements, and biochemical analyses. Blood biomarkers included glucose, urea, creatinine, cystatin C, and glomerular filtration rate. Body mass was recorded at each timepoint to evaluate changes in energy balance. Some mood-related items showed significant changes across the peri-competition phases, including variations in tension, fatigue, anger, and vigor. Body mass increased after the contest, indicating a positive energy balance during recovery. Although group-level biochemical markers remained largely stable, individual analyses revealed relevant fluctuations in glucose, urea, creatinine, and cystatin C. Glomerular filtration rate was lower on the contest day compared to follow-up assessments. The findings highlight the variability in psychological and physiological markers observed in amateur bodybuilders during peri-competition phases, such as mood disturbances, kidney function variations, and post-competition increases in body mass. Coaches and practitioners should closely monitor athletes throughout contest preparation to better support performance, health, and recovery.