Purpose: Indoor climbing is a worldwide sport with particular physiological and physical demands. The purpose of this study was to analyze the effect of sustained indoor climbing until exhaustion on plasma oxidative stress markers, and to relate it to whole-body dynamic exercise performed at the same percentage of maximal oxygen uptake (VO2max).
Methods: Fourteen male indoor climbers continuously climbed a competition-style route until exhaustion. Oxygen consumption and heart rate were continuously monitored during the climbing exercise. One week later, subjects performed a treadmill running protocol with the same duration and percentage of VO2max as that of climbing exercise. Blood samples were collected at rest, immediately after, and 1 h after both exercise protocols to analyze plasma levels of reduced (GSH) and oxidized (GSSG) glutathione, malondialdehyde (MDA), protein sulfhydryl (-SH) and carbonyl (CG) groups, total antioxidant status (TAS) and uric acid (UA), and total blood leukocytes, neutrophil, and lymphocyte counts.
Results: Compared with running, climbing significantly increased the %GSSG, MDA, CG, TAS, and UA and decreased the GSH and -SH content. Blood counts of total leukocytes and neutrophils increased immediately after and 1 h after both running and climbing (P<0.05), although counts were higher in climbing than in running (P<0.05). Lymphocytes significantly increased from baseline to 0 h, although they decreased below baseline 1 h after climbing (P<0.05).
Conclusion: Data demonstrate that indoor climbing induces plasma oxidative stress. Moreover, results suggest that an ischemia-reperfusion prooxidant-based mechanism related to climbers' sustained and intermittent isometric forearm muscle contractions might have significantly contributed to observed plasma oxidative stress.