Effects Of Dual Task On Five-times Sit-to-stand In Younger And Older Adults

Abstract

The five-times sit-to-stand task (FTSTS) is a common functional test used with older adults in the clinic that requires lower extremity muscle strength, balance, stability, and coordination between the trunk and lower extremities.1,2 Slower FTSTS is related to greater deficits in activities of daily living (ADLs) and balance in older adults.2 The effects of dual task on completion times and force output for the FTSTS has not been established. PURPOSE: To determine the effects of dual task and aging on completion time and force output during the FTSTS. METHODS: 12 younger adults (Y) aged 18-30 years and 10 older adults (O) aged 65 years and above participated. Participants stood up and sat down as fast as they could five times, as part of the FTSTS assessment while maintaining feet on a force plate. The participants completed three trials without a cognitive task (Single Task) and with a cognitive task of counting backwards by 3 starting from a random number (Dual Task). Time to complete FTSTS was measured and concentric power during standing was calculated. A task x age ANOVA was conducted. RESULTS: Participants took more time to complete FTSTS during Dual Task (Y, 8.37 ± 1.91 s; O, 10.93 ± 1.91 s) than Single Task (Y, 7.48 ± 1.69 s; O, 9.62 ± 1.69 s; p = 0.005). Also, older adults took longer time to complete FTSTS than younger adults (p = 0.003). Significant interaction for power showed that older adults generated less power during Dual Task (O, 0.80 ± 0.19 Nm/s/BW; Y, 0.91 ± 0.19 Nm/s/BW) despite generating similar power during Single Task (O, 0.96 ± 0.20 Nm/s/BW; Y, 0.96 ± 0.20 Nm/s/BW; p = 0.014). Power generated was significantly less during Dual Task compared to Single Task (p < 0.001). CONCLUSION: Dual tasking during FTSTS task decreases power and overall time in older adults compared to younger adults.