Could scooting be a useful option for aerobic exercise in chronic obstructive pulmonary disease?

Abstract

Background

Many patients with COPD are ventilatory limited and unable to tolerate effective levels of aerobic training. A scooter could be an enticing training modality if muscle activity is partitioned and distal leg muscle activity is emphasized. The aim of this study was to determine whether scooting might emphasize leg heaviness (desired muscle burden), relative to the breathing heaviness, when compared with walking.

Methods

Participants completed two endurance tests, walking and scooting. The intensity for each targeted similar tolerable exercise times (t_limit) simulating comparable training session exposure. Participants scored (Borg_0-10) leg and breathing heaviness throughout each test and the slope calculated. Electromyography was used to quantify leg muscle activity.

Results

15 participants with COPD (mean[SD]: age = 64[11]y; FEV₁ = 52[17]%predicted; FEV₁/FVC = 50[10]%) completed the study. Successful matching of intensity between modalities was demonstrated by similar t_limit (difference [95%CI] = -0.3[-2.8 to 2.1]min). Scooting resulted in more (60[24 to 95]%) activity of the gastrocnemius in the propulsion and less (−82[-91 to −72]%) in the support leg. Rectus femoris activity was reduced (−68[-95 to −41]%) and increased (117[49 to 184]%) in the propulsion and support leg, respectively. There was no significant difference (0.1[-0.1 to 0.2]) in the relationship between breathing and leg heaviness when scooting was compared to walking.

Conclusions

Scooting is associated with increased activity of the distal muscles of propulsion of the scooting leg. However, this is offset by the increased activity of the support leg as it resists the rotational force of propulsion, such that the relationship between breathing and leg heaviness is not altered.