Does exercise intensity increment in exergame promote changes in strength, functional capacity and perceptual parameters in pre-frail older women? A randomized controlled trial

The aim of this study was to compare the effects of two exercise intensities on exergame training program in muscle strength, functional capacity and perceptual parameters in pre-frail older women. Thirty-four women (69.5 +/- 5.4 years) were randomly assigned to either moderate-(MG: 11-13 perceived exertion) or vigorous-exercise intensity group (VG: 14-16 perceived exertion). Muscle strength and functional capacity were evaluated before and after 3 months of training. The affective responses were measured once a week and perceived benefit was evaluated after training period. The MG improved the average power at 60 degrees/s from pre-to post-training (p < 0.002) on the knee extensor (pre = 100.0 +/- 15.9 W; post = 115.2 +/- 22.6 W), flexor (pre = 22.3 +/- 6.1 W; post = 29.1 +/- 7.9 W) and plantiflexor muscles (pre = 11.4 +/- 5.9 W; post = 21.2 +/- 4.2 W). MG presented greater average power at post-training than VG for knee extensor (20%) and flexor muscles (23%) (p < 0.039). There was main time effect of peak torque at 180 degrees/s for knee extensor (pre = 74.15 +/- 14.28 N.m/kg; post = 81.31 +/- 18.4 N.m/kg), flexor (pre = 43.01 +/- 12.43 N.m/kg; post = 48.3 +/- 9.11 N.m/kg) and plantiflexor muscles (pre = 29.2 +/- 13.76 N.m/kg; post = 36.87 +/- 9.7 N.m/kg) as well as average power (pre = 41.15 +/- 15.67 W; post = 48.42 +/- 11.8 W) and work (pre = 99.92 +/- 38.53 J; post = 117.03 +/- 25.56 J) on the knee flexor muscles (p < 0.046). MG improved timed up and go performance from pre-to post-training (pre = 10.0 +/- 0.32 s; post = 8.1 +/- 1.6 s, p = 0.001), whereas both groups improved 10 m-walk performance (pre = 1.33 +/- 0.25 s, post = 1.5 +/- 0.24 s; p = 0.003). Positive affect (2.64 +/- 0.02) and pleasure (15.8 +/- 0.6) for MG were greater than VG at post-training (2.36 +/- 0.03; p < 0.001; 14.4 +/- 0.5; p < 0.03). Therefore, regardless of the exercise intensity, exergame training improved muscle strength and functional capacity in pre-frail older women. However, positive affect and pleasure were reported only when older women practiced exergame with moderate exercise intensity.