24-hour dynamics for serum biomarkers of creatine metabolism after an acute session of exhaustive resistance exercise in active men

Abstract

Summary Introduction Exhaustive exercise adversely affects biomarkers of creatine metabolism yet it remains unknown when the values back toward pre-disturbance conditions. Here, we evaluated a 24-hour post-exercise response in serum guanidinoacetic acid (GAA), creatine and creatinine in young active men subjected to a single session of exhaustive resistance exercise and matched it with exercise-induced changes in serum cortisol, interleukin 6 (IL-6), creatine kinase (CK), and lactate dehydrogenase (LDH). Summary of facts and results Twelve healthy active men (age 22.7 ± 0.8 years; weight 79.8 ± 7.3 kg; height 182.4 ± 4.9 cm; weekly exercise 5.1 ± 1.6 hours) were subjected to a single session of bench press exercise until volitional exhaustion, with venous blood sampled before, immediately after exercise (∼ 2 min), and after 15 min, 60 min and 24 h after the end of exercise. Baseline values for serum GAA, creatine and creatinine were 2.2 ± 0.5 μmol/L, 18.9 ± 3.6 μmol/L, and 72.4 ± 6.0 μmol/L, respectively. Serum GAA significantly dropped for 9.6 ± 7.3% immediately after bench press exercise (95% CI, 5.0 to 14.2; P 0.05). Conclusion A single session of exhaustive resistance exercise induces transient alterations in biomarkers of creatine metabolism, with serum creatinine outlined as a most persistent marker of exhaustion. Exercise-induced changes in creatine metabolism poorly corresponded to perturbations in inflammation and muscle fatigue biomarkers following exercise.