Resistance Exercise Effects on Blood Protein Carbonyls and Glutathione Status: Influence of Partial Vascular Occlusion

Abstract

PURPOSE: This study was designed to ascertain if blood protein carbonyls (PC) and glutathione status would be influenced by three experimental conditions (LO; Light resistance (30% 1RM) with partial occlusion, MR; moderate resistance (70% 1RM) without occlusion, PO; partial occlusion only). METHODS: Eight male subjects (18-30 yr) with >1yr weight training experience and apparently healthy volunteered for this study. On the first visit, 1 RM was assessed for both the biceps curl and calf press. Subjects performed LO or MR to failure in counterbalanced fashion, and then a PO session occurred, all on separate days at 1100 hr. During LO and MR session, three sets of single-arm biceps curl and single-leg calf press were completed to failure. During LO session, cuff occlusion remained in place throughout the 3 sets to failure for the biceps (20 mmHg < SBP) followed by the calf (40 mmHg> arm occlusion pressure). The PO session had equal time of the LO session but without lifting. Blood was obtained from an antecubital vein before (B), immediately after exercise (IAE), and 15 min after treatment (PE), and analyzed for PC and glutathione status. Repeated measures ANOVAs (3 X 3) were used to analyze the data. RESULTS: PC at B did not differ for the 3 conditions (0.05 nmoles.mg.protein−1). Both PO and MR demonstrated significant increases in PC over time that were significantly greater than the LO treatment at IAE (0.13 nmoles.mg.protein−1 immediately post). The GSSG/TGSH ratio at IAE for PO and MR sessions (17%) were significantly elevated compared to the GSSG/TGSH ratio at rest (8%) but was not significantly changed by the LO session (11%) at this time. The GSSG/TGSH ratio returned towards resting levels by PE with no significant difference from rest. CONCLUSION: These results indicate that moderate resistance exercise at 70% of 1RM and mild partial occlusion significantly increased oxidative stress as indicated by blood PC and GSSG/TGSH ratio but light resistance exercise with mild occlusion demonstrated less oxidative stress.