The energy expenditure of people with spinal cord injury whilst walking compared to an able-bodied population

BACKGROUND: In the field of spinal cord injury (SCI) research there is an emphasis on the ability to ambulate. PURPOSE: To determine the ambulation energy expenditure (EE) and factors that affect ambulation EE in SCI participants compared to able-bodied participants. METHODS: This was a cross-sectional study. Participants were recruited from seven SCI rehabilitation units within the Johannesburg area. The following were used: demographic questionnaire to capture participants’ characteristics, modified Ashworth scale for spasticity; goniometer for range of movement (ROM); American Spinal Injury Association (ASIA) scale for patient classification; accelerometer for EE and the six-minute walk test (6MWT) for endurance. Characteristics of the study participants were summarised using descriptive statistics. Data were analysed as follows: two-sample t-test for comparison between the able-bodied and SCI sample and Pearson product moment correlations for relationship between identified factors and EE. RESULTS: Participants comprised 45 in the SCI group and 21 in the able-bodied group. The mean energy expenditure per metre (EE/m) for the SCI participants was 0.33 (± 0.29) calories compared to 0.08 (± 0.02) calories for the able-bodied participants. A decrease in walking velocity resulted in an increase in EE. For SCI participants, every decrease in degree of hip flexion ROM resulted in a 0.003 increase in EE/m walked. A unit decrease in velocity resulted in an increase of 0.41 in EE/m walked. Energy expenditure per metre decreased from ASIA A to ASIA D. Crutch walking utilised 0.34 calories per metre less energy than walking frames (p = 0.03). CONCLUSION: Based on this study’s findings, factors to consider in order to maximise energy efficiency whilst walking are maintaining hip flexion ROM and optimising velocity of walking.