Increasing Walking Speed to Achieve a Pre-training Endurance Shuttle Walk Time of 5-10 min May Improve Test Responsiveness in People with Chronic Obstructive Pulmonary Disease

Purpose: The endurance shuttle walk test (ESWT) was used to evaluate ground-based walking training in chronic obstructive pulmonary disease. During pre-training testing, those who walked 5-10 min on the first ESWT with minimal symptoms performed additional ESWTs at increasing speeds until they were at least moderately symptomatic and terminated the test between 5 and 10 min. This report compares participant characteristics and test responsiveness with participants grouped according to whether or not faster walking speeds were selected for the ESWT during pre-training testing. Methods: We conducted a retrospective analysis of data collected in the intervention group during a randomized controlled trial. The intervention was supervised ground-based walking training, performed two to three times/wk, for 8-10 wk. Prior to and immediately following completion of training, participants completed the 6-min walk test (6MWT), incremental shuttle walk test (ISWT), and ESWT. Results: Data were available on 77 participants (70 ± 9 yr, forced expiratory volume in the first second of expiration [FEV1] 43 ± 15 % predicted). For those whom a faster speed was selected during the pre-training ESWTs were characterized by milder dyspnea and leg fatigue on completion of the baseline 6MWT and ISWT (P <.05 for all). On training completion, the change in ESWT was greater in those for whom a faster speed was selected (376 ± 344 sec vs 176 ± 274 sec; P =.017). Conclusions: Participants who report modest symptoms on completion of the pre-training 6MWT or ISWT may achieve a long pre-training ESWT time. In this situation, repeating the pre-training ESWT at a faster walking speed to achieve an exercise time between 5 and 10 min with moderate symptoms may be advantageous.