Implications on older women of age- and sex-related differences in activation patterns of shoulder muscles: A cross-sectional study.

We conducted a cross-sectional study to assess differences in neuromotor attributes of shoulder muscles between age groups in both sexes and to better understand functional disorders in older women. Twenty young (20-42 years old), 20 middle-aged (43-67), and 20 older (> 68) adults participated in a comparative surface-electromyography study of five muscles. We identified age-related differences in women, especially in scapula stabilizer muscles. There was a tendency for both sexes of delayed onset times with increasing age, excepting the upper trapezius muscle in females. The results highlight the importance of understanding musculoskeletal aging in women to adequately guide physical therapeutic approaches.