To characterize the burden of care and musculoskeletal discomfort associated with caring for adults with chronic physical disability among informal caregivers and to describe the most physically demanding caregiving activities and contributing factors, as perceived by informal caregivers of adults with physical disabilities.

A mixed methods approach was used for the study. Forty-six informal caregivers of adults with physical disability participated.

Most caregivers were classified as "high burden" caregivers. They reported high levels of physical strain and musculoskeletal discomfort. Caregivers identified several activities related to mobility and self-care as the most physically demanding. Factors affecting physical demand included caregiver and care-recipeint characteristics, activity requirements, and the physical environment.

Interventions that target high-demand caregiving activities, including all three aspects of caregiving activity performance, are necessary to support adults with disabilities in the home and their caregivers.