To find out how much physical activity in the form of walking can be tolerated by adults admitted for inpatient rehabilitation after hip fracture.Using a phase I dose-response design, in addition to usual scheduled rehabilitation care participants without cognitive impairment were supervised to walk for a prescribed length of time on 5 consecutive days. Doses started at 3 min and were escalated when three participants successfully completed a dose. Secondary outcomes included physical activity and the Ambulatory Self-Confidence Questionnaire (ASCQ).The maximum tolerated dose of walking for the 13 participants (4 men and 9 women; mean age 81 years, SD 10) was 6 min. At 10 min only 1 of 5 participants was able to complete the dose. The main reason for not tolerating the prescribed dose was fatigue. Participants had relatively low levels of daily physical activity (mean 507 steps/day), and lacked confidence in their walking (ASCQ mean 4.6).Physical activity guidelines for older people are not appropriate for patients in active inpatient rehabilitation recovering from hip fracture where other factors such as fatigue may limit physical activity levels. These results can be taken into account when designing rehabilitation programmes after hip fracture. Implications for Rehabilitation Hip fracture is a common and serious fracture with ongoing disability for which people require inpatient rehabilitation to prepare for return to independent living in the community. The maximum tolerated dose of walking of 6 minutes suggests physical activity guidelines for older people are not applicable for those receiving active inpatient rehabilitation after hip fracture. The maximum tolerated dose of walking of 6 minutes during inpatient rehabilitation suggests rehabilitation programmes be structured to allow adequate time for recovery.