Daily acute intermittent hypoxia combined with walking practice enhances walking performance but not intralimb motor coordination in persons with chronic incomplete spinal cord injury.
Study Goal
The researchers aimed to determine whether daily acute intermittent hypoxia (AIH) combined with walking practice improves overground walking performance and intralimb motor coordination in individuals with chronic, incomplete spinal cord injuries.
Results Summary
Participants showed improved walking speed and endurance after daily AIH + walking practice, with benefits persisting for weeks. The greatest improvements occurred in those using bilateral walking aids, but no significant changes in intralimb coordination were observed.
Population
11 individuals with chronic (>1 year), incomplete spinal cord injuries.
Effective Dosage
15 episodes of 10.0% O₂, 90 seconds each, daily for 5 consecutive days.
Duration
5 consecutive days.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
daily bouts of breathing low oxygen (acute intermittent hypoxia, AIH) prior to locomotor training | increase | overground walking speed and endurance | humans with SCI | persistent (weeks) | elicited persistent (weeks) improvement | #1 |
daily AIH combined with walking practice (AIH + WALK) | increase | overground walking performance | persons with chronic, incomplete SCI | - | improved | #2 |
daily AIH combined with walking practice (AIH + WALK) | increase | intralimb motor coordination | persons with chronic, incomplete SCI | - | improved | #3 |
daily AIH + WALK | increase | overground walking performance (speed and endurance) | participants | - | improved | #4 |
SHAM+WALK | no change | overground walking performance (speed and endurance) | participants | - | not | #5 |
daily AIH + WALK | decrease | 10MWT time | participants | - | decreased | #6 |
daily AIH + WALK | increase | 6MWT distance | participants | - | increased | #7 |
daily AIH + WALK | increase | walking speed and endurance | - | persisted for weeks after treatment | improved | #8 |
daily AIH + WALK | increase | speed | participants who used bilateral walking aids | - | Greatest improvements | #9 |
daily AIH + WALK | no change | EV and ACC | - | - | No change | #10 |
UNLABELLED: Persons living with incomplete spinal cord injuries (SCI) often struggle to regain independent walking due to deficits in walking mechanics. They often dedicate many weeks of gait training before benefits to emerge, with additional training needed for benefits to persist. Recent studies in humans with SCI found that daily bouts of breathing low oxygen (acute intermittent hypoxia, AIH) prior to locomotor training elicited persistent (weeks) improvement in overground walking speed and endurance. AIH-induced improvements in overground walking may result from changes in control strategies that also enhance intralimb coordination; however, this possibility remains untested. Here, we examined the extent to which daily AIH combined with walking practice (AIH + WALK) improved overground walking performance and intralimb motor coordination in persons with chronic, incomplete SCI. METHODS: We recruited 11 persons with chronic (> 1 year), incomplete SCI to participate in a randomized, double-blind, balanced, crossover study. Participants first received either daily (5 consecutive days) AIH (15, 90-s episodes of 10.0% O RESULTS: Participants improved overground walking performance (speed and endurance) after daily AIH + WALK, but not SHAM+WALK. Following daily AIH + WALK, participants decreased their 10MWT time at T CONCLUSIONS: Consistent with prior studies, daily AIH + WALK triggered improvements in walking speed and endurance that persisted for weeks after treatment. Greatest improvements in speed occurred in participants who used bilateral walking aids. No change in EV and ACC may suggest that intralimb motor coordination was not a significant gait training priority during daily AIH + WALK.