Differences in power and performance during sit-to-stand test and its relationships to functional measures in older adults with and without Parkinson's disease.

STS repetitions and power values estimated through the 30-s STS test were lower in older people with PD than without PD. Overall, STS power measures were similarly associated with functional performance as STS repetitions, indicating these power equations can be implemented when assessing lower extremity function in older people with PD.