Effect Of Low Intensity Resistance Exercise Training On Cognitive Function In Middle-aged And Older Individuals: 91 Board #5 May 27 9:30 AM - 11:30 AM

PURPOSE:Many studies have reported that aerobic exercise training improves cognitive function (CF), even with low-intensity (e.g. walking) (Kramer et al. 1999; Hillman et al. 2008). Alternatively, moderate (MRT) to high intensity RT (60-80% 1RM) improves CF (Chang et al. 2012). However, older individuals and patients with chronic disease often have difficulty with higher exercise loads due to declining cardiovascular and musculoskeletal systems. The purpose of this study was to examine the effect of low intensity resistance exercise training (LRT) on CF in middle-aged and older individuals. Given that an acute bout of even low intensity resistance exercise improves CF albeit less effective than higher intensity (Tsukamoto et al. 2017), we hypothesized that LRT would improve CF although its effect might be lower than higher intensity training. METHODS:50 healthy middle-aged and older individuals (age: 50 to 77 years) were randomly classified into three groups (control (CON), LRT (40%1RM), and MRT (60%1RM)). Resistance exercise programs were leg extension, seated leg curl, leg press, and chest press. For each exercise, all participants performed 14 repetitions for three sets with 2 minutes interval. LRT and MRT participants completed all these exercise for three times per week and CON participants maintained their conventional lifestyle. CF (working memory (WM), short memory (SM), and inhibitory control (IC)) were determined with reading span test, face-name matching task, and color-word Stroop task, respectively. Each task was performed at before the intervention (PRE), 12 weeks (12W), and 24 weeks (24W) of the intervention period. RESULTS: There was significant interaction for the IC score (p = 0.021). As compared with the PRE, the IC at the 12W did not change in the MRT (p = 0.184), while tended to improve for the LRT (p = 0.065), and significantly declined in the CON (p = 0.020). At the 24W, the IC score did not change significantly for all conditions as compared with the PRE. The score of WM and SM did not change significantly for all conditions throughout the intervention. CONCLUSIONS: The finding suggests that even with a lower load, chronic RT may improve IC in middle-aged and older individuals. However, the exercise intensity, training period, and task specificity for the CF should be further elucidated.