The effects of experience on the energy cost of wheelchair propulsion

Background. Gross mechanical efficiency (GE) of experienced wheelchair users is significantly higher than novice able-bodied individuals suggesting energy expenditure (EE) may be reduced in experienced individuals. With knowledge of the energy expended during wheelchair propulsion, nutritional recommendations can be provided for individuals in their early stages of rehabilitation and for habituated wheelchair users. Aim. To investigate the effects of experience on EE during wheelchair propulsion at fixed power outputs (PO's). Design. This was an experimental study. Setting. The experiment was conducted in a controlled University laboratory. Population. Thirty-one individuals took part in this study. Methods. Participants were assigned to a group in accordance to their wheelchair propulsion experience: 1) novice able-bodied individuals (NOV; N.=11), 2) able-bodied individuals habituated to three weeks practice (PRAC; N.=11) and 3) experienced paraplegic daily-wheelchair users (EXP; N.=9). Oxygen uptake, EE, GE% and HR were measured during wheelchair propulsion on a motorised treadmill at 10, 18 and 26 W. Results. Energy expenditure analysis revealed a significant main effect of PO and group (P<0.01) and a significant group by PO interaction (P<0.01). Followup pair-wise comparisons revealed significantly lower EE in EXP compared to both other groups (P<0.01), but no difference was shown between NOV and PRAC (P=0.15). A lower relative EE of 20,22 and 32% was reported in the EXP group compared to the NOV group at 10, 18 and 26 W respectively. In comparison to the PRAC group, the EE of the EXP group was 10, 16 and 26% lower in relative terms at the same PO's respectively. Conclusion. The EXP expended less EE compared to both NOV and PRAC. Clinical Rehabilitation Impact. This finding has great implications for nutritionists and health care professionals working in the field of physical activity and weight management since the EE is influenced by experience.