ABSTRACT
Objective To approach the effects of full Marathon on striated muscle and renal function of Marathon amateurs without complaints. Methods A prospective self-paired design study was conducted. The amateurs without body discomfort, hematuria, brown urine, or persistent muscle pain within 1 week after the 2012 Xiamen International Marathon Race were enrolled voluntarily. The peripheral blood and random urine specimens of all subjects under static status 1 week before the race and after the race instantly (within 10 minutes after finishing the race) were collected to detect markers of renal function and striated muscle injury. Results Sixty-one subjects were included in the final analysis of the study with full Marathon of 42.195 km and mean race time of (297.05± 55.60) minutes. Compared with those under static status before the race, the markers of renal function including the levels of urinary N-acetyl-beta-D-glucusamidase [NAG (U/L): 64.00 (54.50, 85.50) vs. 9.50 (8.10, 11.50)], urinary β2-microspheres protein [β2-MG (μg/L): 261.00 (128.50, 1 608.00) vs. 66.60 (33.75, 123.00)], random urinary creatinine [UCr (μmol/L): 19 066.56±10 938.31 vs. 5 872.52±4 363.20] and serum creatinine [SCr (μmol/L): 129.97±25.84 vs. 97.39±14.51] immediately after the race were significantly increased (all P < 0.01); the markers of muscle injury including the levels of serum creatine kinase [CK (U/L): 864.00 (504.00, 1 644.00) vs. 164.00 (128.00, 256.00)], lactic dehydrogenase [LDH (U/L): 383.26±141.69 vs. 182.23±41.12], myoglobin [Mb (mg/L): 1 880.00 (1 080.00, 3 300.00) vs. 42.00 (36.00, 54.50)], alanine aminotransferase [ALT (U/L): 27.0 (19.5, 38.0) vs. 24.0 (15.0, 29.5)] and aspartate transaminase [AST (U/L): 52.07±25.13 vs. 28.28±11.86] were also significantly increased (all P < 0.01), and the increase in CK, Mb, and LDH were more significant. It was shown by correlation analysis that CK after race was negatively correlated with age (r = -0.352, P = 0.005) and body mass index (r = -0.271, P = 0.035), and it was positively correlated with racing time (r = 0.387, P = 0.002) and urinary β2-MG after the race instantly (r = 0.364, P = 0.004). Mb after race was negatively correlated with body mass index (r = -0.331, P = 0.009), and it was positively correlated with urinary β2-MG after the race instantly (r = 0.315, P = 0.013). LDH after race was negatively correlated with age (r = -0.275, P = 0.032) and body mass index (r = -0.377, P = 0.003), and it was positively correlated with urinary β2-MG after the race instantly (r = 0.424, P = 0.001). Conclusion Full Marathon could significantly impact striated muscle and renal function of Marathon amateurs without complaints.