Effect Of Muscle Oxygenation During Resistance Exercise On Lipid Peroxidation

Abstract

PURPOSE To examine the relationship between muscle oxygenation and lipid peroxidation following two different resistance exercise protocols. METHODS Eleven experienced resistance trained male athletes (20.8 ± 1.3 yr; 96.2 ± 14.4 kg, 182.4 ± 7.3 cm) performed four sets of the squat exercise using either a low-intensity, high volume (LI; 15 repetitions at 60% one-repetition maximum [1-RM] or high intensity, low volume (HI; 4 repetitions at 90% 1-RM load). Venous blood samples were obtained before (PRE), immediate (IP), 20-(20P) and 40-min (40P) postexercise. Continuous wave near infrared spectroscopy was used to measure muscle deoxygenation in the vastus lateralis during exercise. Deoxygenated Hb/Mb change was used to determine reoxygenation rate during recovery. RESULTS No significant difference between LI and HI was seen in plasma malondialdehyde (MDA) concentrations. However, there was a significant main effect for MDA concentrations and time. Plasma MDA concentrations at IP (6.13 ± 1.19 μmol·L-1) were significantly (p<0.05) higher than PRE (5.62 ± 1.07 μmol·L-1) and 40P (5.29 ± 1.15 μmol·L-1). There was no relationship between the extent of muscle deoxygenation and changes in MDA concentrations. However, significant correlations were observed between plasma MDA concentrations at IP and the half-time recovery (T1/2 recovery) of muscle reoxygenation (r = 0.45) and between T1/2 recovery and the area under the curve for MDA concentrations (r = 0.44). CONCLUSIONS There was no significant difference between the two resistance exercise protocols in plasma MDA concentrations. However, the time for muscle reoxygenation did correlate moderately with elevations in plasma MDA concentrations.