Resistance exercise training attenuates exercise-induced lipid peroxidation in the elderly

Area of Science:

• Exercise Physiology
• Oxidative Stress Research
• Gerontology

Background:

• Oxidative stress increases with age and can be exacerbated by exercise.
• Lipid peroxidation (LIPOX) is a marker of oxidative damage.
• The effects of resistance exercise (RX) on LIPOX, particularly post-aerobic exercise, are not fully understood.

Purpose of the Study:

• To investigate the impact of a 6-month resistance exercise program on basal and post-aerobic exercise lipid peroxidation (LIPOX) in older adults.
• To compare the effects of low-intensity (LEX) and high-intensity (HEX) resistance training versus a control group.

Main Methods:

• Sixty-two older adults (mean age 68.4 years) were randomized into control (CON), LEX (50% 1RM, 13 reps), or HEX (80% 1RM, 8 reps) groups.
• Subjects trained 3 times/week for 6 months.
• Lipid peroxidation was assessed by measuring thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides (PEROX) before and after a graded aerobic exercise test (GXT).

Main Results:

• Resistance exercise had no effect on resting LIPOX levels.
• Post-GXT TBARS were significantly lower in LEX (14%) and HEX (18%) groups compared to CON.
• Post-GXT PEROX levels were lower in LEX and HEX groups compared to CON.
• Serum total and non-protein thiols increased in LEX and HEX groups post-training.

Conclusions:

• Six months of resistance exercise effectively reduces lipid peroxidation following aerobic exercise in older adults.
• Resistance exercise may provide cross-protection against oxidative stress induced by aerobic exercise.
• Improvements in the thiol component of the antioxidant defense system may mediate these protective effects.