The Impact of Partial Vascular Occlusion on Oxidative Stress Markers during Resistance Exercise.

This study sought to examine the effects of partial vascular occlusion (PVO) on oxidative stress markers in response to resistance exercise and at rest in young resistance-trained males. 12 resistance-trained males performed 6 conditions in random counterbalanced order: rest (R), low-intensity (LIRE: 30% 1RM) and moderate-intensity (MIRE: 70% 1RM) resistance exercise with or without PVO. Blood samples were obtained before and immediately after each condition and plasma protein carbonyls (PC), glutathione ratio, oxygen radical absorbance capacity (ORAC), and xanthine oxidase (XO) were evaluated. The addition of PVO resulted in significantly greater plasma PC and glutathione ratio in the rest condition. During LIRE the addition of PVO significantly attenuated plasma PC. The MIRE condition, independent of PVO, resulted in significantly higher PC concentration and glutathione ratio compared to the rest and LIRE conditions. The addition of PVO during MIRE resulted in a significant increase in PC. Thus, this study revealed that PVO increased oxidative stress at rest and enhanced the oxidative stress response to MIRE, but when combined with LIRE oxidative stress was attenuated. These findings suggest that the utilization of PVO during LIRE may alter ROS-induced accumulation in the blood which may influence cellular signaling.

Oxidative stress and inflammation response following aerobic exercise: role of ethnicity.

African-Americans are at a significantly greater risk for developing several diseases and conditions. These conditions often have underlying oxidative stress mechanisms. Therefore the purpose of this investigation was to ascertain the post-exercise oxidative response to a single bout of aerobic exercise in African-American and Caucasian college-age females. A total of 10 African-American and 10 Caucasian females completed the study. Each subject had her VO2 max measured while exercising on a treadmill. A week later, each subject returned to the laboratory and performed a 30-min run at 70% of her VO2max. Blood samples were taken immediately prior to and following exercise for analysis. Lipid hydroperoxides, protein carbonyls, malondialdehyde, xanthine oxidase, glutathione in the reduced (GSH) and oxidized (GSSG) forms, TNFα and interleukin 6 were measured from blood taken before and after exercise. Significance was set at p≤0.05 a priori. Xanthine oxidase was the only measure that did not significantly increase following exercise. All other markers showed a significant elevation in response to the exercise bout with no difference between groups except that the Caucasian group had significantly higher malondialdehyde post-exercise compared to the African-American group. This cohort of college-age African-American and Caucasian females showed little difference in their response to a single 30-min run at 70% of their max in the markers of oxidative stress within the blood.

Day to Day Variability and Reliability of Blood Oxidative Stress Markers within a Four-Week Period in Healthy Young Men.

The present study aimed to determine the day to day variability and reliability of several blood oxidative stress markers at rest in a healthy young cohort over a four-week period. Twelve apparently healthy resistance trained males (24.6 ± 3.0 yrs) were tested over 7 visits within 4 weeks with at least 72 hrs between visits at the same time of day. Subjects rested 30 minutes prior to blood being obtained by vacutainer. Results. The highest IntraClass correlations (ICC's) were obtained for protein carbonyls (PC) and oxygen radical absorbance capacity (ORAC) (PC = 0.785 and ORAC = 0.780). Cronbach's α reliability score for PC was 0.967 and for ORAC was 0.961. The ICC's for GSH, GSSG, and the GSSG/TGH ratio ICC were 0.600, 0.573, and 0.570, respectively, with Cronbach's α being 0.913, 0.904, and 0.903, respectively. Xanthine oxidase ICC was 0.163 and Cronbach's α was 0.538. Conclusions. PC and ORAC demonstrated good to excellent reliability while glutathione factors had poor to excellent reliability. Xanthine oxidase showed poor reliability and high variability. These results suggest that the PC and ORAC markers were the most stable and reliable oxidative stress markers in blood and that daily changes across visits should be considered when interpreting resting blood oxidative stress markers.

Resistance exercise effects on blood glutathione status and plasma protein carbonyls: influence of partial vascular occlusion.

Seven weight-trained males performed both light resistance with partial occlusion (LRO: 30% 1 RM) and moderate resistance (MR: 70% 1 RM) to failure to ascertain whether blood protein carbonyls (PC) and glutathione status was altered compared to partial occlusion (PO) in a counterbalanced fashion. PO was identical in duration to the LRO session and all sessions were on separate days. PC did not differ for the three conditions at PRE (0.05 nM mg protein(-1)). PC significantly increased for PO and MR over time and was greater than the LRO treatment at POST (0.13 nM mg protein(-1)). The GSSG/TGSH ratio at PRE did not differ across treatments (8%) whereas the ratio at POST was significantly elevated for PO and MR treatments (17%). In contrast, no change occurred for the LRO session at any time. These results indicate that MR to failure and PO can significantly increase blood oxidative stress but LRO did not elicit oxidative stress.