Effects of eccentric versus stretching exercise training on cognitive function of older women.

Abstract

Exercises focusing on eccentric contractions may stimulate the brain better, improving cognitive function. We tested the hypothesis that executive function and attention would improve more after eccentric resistance exercise (ECC) than stretching exercise (STRETCH) training. Healthy older women (65-75y) underwent either ECC (n=14) or STRETCH (n=14) intervention for 8 weeks. ECC consisted of 7 exercises emphasizing eccentric contractions while STRETCH performed 12 stretching exercises, with supervised sessions undertaken twice weekly accompanied by a home-based program. Executive function and attention were assessed using the Stroop test of color naming (STCN) and conflicting color words, symbol digit modalities test, digit span test (DST), and trail making tests (TMT-A, TMT-B), and 6 physical function tests were undertaken before and after the 8-week training period. Fasting blood samples were obtained before and after the training. A significant (p<0.05) group x time interaction effect was evident for STCN, DST and TMT-A, with only ECC showing improvements (DST:14.7±27% and TMT-A:10.2±12%) from pre- to post-training. No significant changes in other cognitive function tests were found for either group. All physical function tests except one-leg balance test showed greater improvement (p<0.05) for ECC than STRETCH. No significant changes in blood lipid profile and brain-derived neurotrophic factor were found, but serum glucose concentration and glycosylated hemoglobin decreased (p<0.05) in ECC. These results suggest that a short-term eccentric exercise intervention was effective in enhancing components of cognitive and physical function of older women and may prove a useful strategy in combating age-related decline in cognitive and physical function.