The effects of high-intensity interval training on postural control, dynamic balance, and muscular strength among older adults.

Abstract

Aging adults are at an increased risk of falling, dependency, and disability due to a decline in physical conditioning. Research has determined muscle weakness and poor balance are associated with these risks. Resistance training may cause muscular strength improvements at any velocity or intensity. High-intensity interval training (HIIT) is an emerging style of fitness, which has shown to be beneficial to muscular strength. PURPOSE: To determine the effects of HIIT on postural sway, dynamic balance, and lower body strength among active older adults. METHODS: The experimental group (EG) participated in the intervention two times per week for 4-weeks. The control group (CG) continued their current fitness routine. HIIT participants utilized exercises which simulated muscle groups that influence balance. Participants completed interval bouts ranging from 20-30s accompanied by a 30 - 40s recovery phase. Participants were assessed on postural sway in tandem, semi-tandem, and single leg stances performed on the TekscanTM pressure mat. Each stance was performed with eyes-open (EO) and eyes-closed (EC). Dynamic balance was measured with the Timed-Up-and-Go (TUG), and lower extremity strength was measured with the 30-Second Chair Stand test. The Wilcoxon Sum of Ranks and Mann-Whitney U tests were used to determined differences within and between groups, respectively. RESULTS: Postural sway significantly improved during eyes open stances (p < 0.05). The experimental group did show a moderate to strong (d >.30) reduction in sway in four different EO stances. The EC stances in the EG showed three significant improvements (p > 0.05). The EG experienced significant improvements in the TUG (p =.04) and approached significant increases in chair stand performance (p =.07). CONCLUSION: HIIT significantly improved dynamic balance and muscular strength, and meaningfully improved postural sway. Future research should utilize HIIT for a longer duration to examine its effects.