OBJECTIVE: To describe metabolic responses accompanying 4 different locomotor training (LT) approaches. DESIGN: Single-blind, randomized controlled trial. SETTING: Rehabilitation research laboratory, academic medical center. PARTICIPANTS: Individuals (n = 62) with minimal walking function due to chronic motor-incomplete spinal cord injury. INTERVENTION: Participants trained 5 days/week for 12 weeks. Groups were treadmill-based LT with manual assistance (TM), transcutaneous electrical stimulation (TS), and a driven gait orthosis (DGO) and overground (OG) LT with electrical stimulation. MAIN OUTCOME MEASURES: Oxygen uptake (VO2), walking velocity and economy, and substrate utilization during subject-selected "slow", "moderate", and "maximal" walking speeds. RESULTS: VO2 did not increase from pretraining to posttraining for DGO (0.00 +/- 0.18L/min, p = 0.923). Increases in the other groups depended on walking speed, ranging from.01 +/- 0.18m/s (p = 0.860) for TM (slow speed) to 0.20 +/- 0.29m/s (p = 0.017) for TS (maximal speed). All groups increased velocity but to varying degrees (DGO 0.01 +/- 0.18 Ln (m/s), p = 0.829; TM 0.07 +/- 0.29 Ln (m/s), p = 0.371; TS 0.33 +/- 0.45 Ln (m/s), p = 0.013; OG 0.52 +/- 0.61 Ln (m/s), p = 0.007). Changes in walking economy were marginal for DGO and TM (0.01 +/- 0.20 Ln (L/m), p = 0.926, and 0.00 +/- 0.42 Ln (L/m), p = 0.981) but significant for TS and OG (0.26 +/- 0.33 Ln (L/m), p = 0.014, and 0.44 +/- 0.62 Ln (L/m), p = 0.025). Many participants reached respiratory exchange ratios >= 1 at any speed, rendering it impossible to statistically discern differences in substrate utilization. However, after training, fewer participants reached this ceiling for each speed (slow 9 versus 6, n = 32; moderate 12 versus 8, n = 29; and maximal 15 versus 13, n = 28). CONCLUSIONS: DGO and TM walking training was less effective in increasing VO2 and velocity across participant-selected walking speeds, while TS and OG training was more effective in improving these parameters and also walking economy. Therefore, the latter 2 approaches hold greater promise for improving clinically relevant outcomes such as enhanced endurance, functionality, or in-home/community ambulation.

Full text (sometimes free) may be available at these link(s):      help

• DOI
• PubMed
• PDF locator
• publisher