Effects Of Long-term Elastic Resistance Training On Oxidative Damage Of DNA In Older Adults

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It is theorized that age-related physiological changes are a consequence of the accumulation of random oxidative damage to deoxyribonucleic acid (DNA), lipids, and proteins. The major by-product of oxidative DNA damage, 8-Oxo-7,8-dihydro-2’-deoxyguanosine (8-oxo-dG), is the most extensively analyzed oxidative stress marker. The concentration of this biomarker increases as age increases. A higher concentration of 8-oxo-dG is related to diseases such as Alzheimer’s, osteoporosis and oncogenesis. Despite the multiple benefits of resistance training on the aging process, the effect upon mitochondrial function and oxidative stress in older adults is unknown. PURPOSE: To determine the effects of a long-term, moderate-intensity elastic resistance training (ERT) program on oxidative damage of DNA in older adults. METHODS: 46 sedentary older adults (69.1 ± 5.1 yr) were randomized into two groups: Control Group (CG) (n=15) and ERT group (ERTG) (n=31). A 32-wk ERT program was performed 2d/wk with 6 exercises (3 for upper and 3 for lower extremities) completed for 4 sets of 15 repetitions. Perceived effort was 6-7 on the OMNI-RES scale for elastic bands during the first 4 wks and at 8-9 for the final 28 wks. Urine 8-oxo-dG was analyzed using high-performance liquid chromatography at baseline, 16 and 32 wks. Urinary levels of 8-oxo-dG were calculated relative to creatinine levels. Trial (3) by group (2) repeated measures ANOVA was used to determine differences. RESULTS: 8-oxo-dG was not different between groups at baseline (CG: 3.20 ± 2.51; ERTG: 3.72 ± 2.47 nmol/nmol creatinine). ERTG showed a significant (p<0.05) decrease in 8-oxo-dG for time and group of 26.07% at 16 wks and 49.43% at 32 wks. CONCLUSION: It is possible to reduce oxidative damage of DNA in older adults through regular ERT performed at moderate intensity. A longer training duration provokes greater effects on oxidative stress metabolism. These results highlight the possibility of using a non-invasive and low cost diagnostic method in conjunction with a simple and inexpensive ERT to prevent oxidative stress in older adults.