Effect of familiarization to treadmill walking on gait profile and walking distance in subjects with claudication

Background: Treadmill training improves walking ability of patients with claudication. One of the possible mechanisms leading to increase in walking distance may be improvement in walking economy through exercise-mediated alterations in gait parameters. The assessment of walking distance in these patients is usually performed on the treadmill. However, insufficient familiarization to treadmill walking may affect comparison of pre- and post-training results, particularly in the situation when the same research tool is used for both the training and the assessment.
Aim of the study: This study investigated the time of familiarization to treadmill walking in patients with claudication needed to avoid the above problem. Method: Forty-three patients (aged 50-70) with peripheral arterial disease and intermittent claudication (Fontaine II B) were evaluated in this study and divided into two groups. Subjects with walking distance of no more than 100 m were assigned to group I (n = 17) and those with walking distance of more than 100 m to group II (n = 26). All patients performed five successive walking trials on the treadmill (3 km/h, 0% grade). During each trial the patients in group I were walking to the onset of claudication pain. The pain-free walking distance was assessed. Each trial in group II consisted of two minutes’ treadmill walking. The gait parameters (stride length, cadence, stride CV) and HR were recorded.
Results: Following the first 3 trials a 15% increase in the stride length, 13% cadence decrease and 50% stride CV decrease (p < 0.05) were observed in group II. Also 17.8% HR decrease was noted at the same time. Patients in group I increased pain-free walking distance by 55% within 4 trials (p < 0.05).
Conclusion: At least 6 min. prior to data collection is needed to provide adequate treadmill familiarization in patients with claudication.