Resistance training lowers exercise-induced oxidative stress and homocysteine levels in overweight and obese older adults

Objective: To compare exercise-induced oxidative stress and levels of homocysteine and cholesterol in normal-weight and overweight older adults after resistance exercise (RX). Research Methods and Procedures: This interventional study was conducted at a wellness center. Forty-nine older adults (age range, 60 to 72 years) were stratified by BMI (< 25 kg/m(2) normal weight, >= 25 kg/m(2) overweight/obese) and then randomly assigned to either a control non-exercise group or an RX group. The RX group completed a 6-month training program. Exercise-induced lipid hydroperoxides (PEROXs) and thiobarbituric-reactive acid substances, homocysteine, lipoprotein a, cholesterol, and high-density lipoprotein cholesterol were measured before and after the 6-month RX program. Results: PEROXs and thiobarbituric-reactive acid substances were lower in both the overweight/obese and normal-weight RX-trained groups compared with control groups (p < 0.05). Homocysteine levels were lower in both overweight/obese and normal-weight RX groups compared with control groups (p < 0.05). Lipoprotein a, total cholesterol, and high-density lipoprotein cholesterol were not different in normal-weight and overweight/obese groups before or after RX The change in muscle strength was correlated with homocysteine at 6 months (r = -0.452, p < 0.05), whereas the change in PEROXs was correlated with the change in body fat (r = -0.329). Discussion: To our knowledge, these data are the first to show that RX reduces exercise-induced oxidative stress and homocysteine regardless of adiposity, indicating that this protection can be afforded in an older, overweight/obese population as effectively as in healthy older adults. These data suggest that RX may afford some protection against emerging cardiovascular risk factors using a mode of exercise that supports body weight.