Sprint Interval Training During Rehabilitation After Spinal Cord Injury (SprintSCI)

Immediately following a spinal cord injury (SCI), patients are admitted to inpatient rehabilitation where they undergo physical reconditioning in preparation for a return to home setting. The current standard of practice for aerobic training is performing arm-ergometry for 25 mins at a frequency of three times per week. Given the move towards shortened length of stay during inpatient rehabilitation, performing MICT can consume a considerable amount of therapy time. Sprint interval training (SIT) has been shown to elicit similar improvements in physical capacity, despite a reduced time commitment to MICT. However, there are no controlled trials comparing the effects of SIT to MICT in individuals with SCI undergoing inpatient rehabilitation. The primary aim of this study was to investigate the efficacy of a five-week, thrice weekly 10 min SIT program and compare outcome measures to a traditional 25 minute MICT program on the arm-ergometer in individuals with SCI undergoing inpatient clinical rehabilitation. It was hypothesized that five weeks of SIT and MICT would induce similar changes in maximal and sub-maximal exercise performance, self-efficacy for exercise, and exercise enjoyment, despite large differences in training volume and time commitment. It was also hypothesized that SIT would be well tolerated and elicit higher levels of cardiovascular strain than MICT.

Participants were randomized to one of two groups: (A) sprint interval training (SIT) or (B) moderate intensity continuous training (MICT).

Training was performed three times a week for five weeks. Each session began with a 2 minute warm up, and concluded with a 3 minute cool down. Following the warm-up, participants performed 20 minutes of arm cycling at a self-selected cadence at 45-65% of their peak power output. Total training duration was 25 mins.

The SIT protocol was adopted from Gillen and colleagues (See Ref), and consisted of 3 x 20 second "all-out" efforts at ≥ 100% of an individuals peak power output. Each sprint was interspersed by 120 seconds of active recovery at 10% of an individuals peak power output. Total training duration was 10 mins.

Participants performed three 5-minute steady state workloads on the arm-ergometer at power outputs corresponding to RPE's of 8, 10 and 12. Participants were given a minimum of 2 minutes, and a maximum of 5 minutes of rest in between each workload.

Using a self-reported questionnaire, participants rated how confident they are with regards to performing and carrying out regular physical activities and exercises.

Participants completed the Physical Activity Enjoyment Scale (PACES) in order to asses the level of enjoyment with the training intervention they received.

Through a questionnaire, participants rated how much shoulder pain, bodily pain, and physical discomfort they typically experience throughout the day and how much pain they experienced with the intervention they were allocated to.

Inclusion Criteria: Participants with sub-acute spinal cord injury (time since injury: 14 - 182 days) Undergoing inpatient rehabilitation Aged 18-65 years Injury level at the second cervical vertebrae (C2) or below Exclusion Criteria: - Unable to perform arm-ergometry training

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