We studied the amount of time required for treadmill familiarisation in older people and also whether familiarised treadmill walking could be generalised to overground walking. Sixteen healthy volunteers over 65 years of age walked on a level overground walkway and on a treadmill at the same speed for up to 15 min. A motion measurement system was used to measure the sagittal-plane kinematics of the knee and cadence during overground walking and after 0, 2, 4, 6, 8, 10, 12 and 14 min of treadmill walking. Older adults had not familiarised to the treadmill within 15 min as many participants continued to hold the treadmill's handrails and as reliability and absolute difference scores were still changing. Participants were most familiarised after 14 min on the treadmill. Furthermore, treadmill walking after 14 min was not closely related to overground walking in older adults, with measures on the treadmill only being able to predict knee angles during overground to within 8.0 degrees , or cadence to within 16.6 steps/min with 95% confidence. Treadmill walking in older adults after a single 15-min training session could not be generalised to overground walking.