Arm Crank and Wheelchair Ergometry Produce Similar Peak Oxygen Uptake but Different Work Economy Values in Individuals with Spinal Cord Injury

Objective.To study whether values for peak oxygen uptake (VO2peak) and work economy (WE) at a standardized workload are different when tested by arm crank ergometry (ACE) and wheelchair ergometry (WCE).Methods.Twelve paraplegic men with spinal cord injury (SCI) in stable neurological condition participated in this cross-sectional repeated-measures study. We determinedVO2peakand peak power output (POpeak) values during ACE and WCE in a work-matched protocol. Work economy was tested at a standardized workload of 30 Watts (W) for both ACE and WCE.Results.There were no significant differences inVO2peak(mL·kg−1·min−1) between ACE (27.3±3.2) and WCE (27.4±3.8) trials, and a Bland-Altman plot shows that findings are within 95% level of agreement. WE or oxygen consumption at 30 W (VO2-30W) was significantly lower during WCE compared to ACE (P<0.039). Mean (95% CI)POpeak(W) were 130 (111–138) and 100 (83–110) during ACE and WCE, respectively.Conclusion.The findings in the present study support the use of both ACE and WCE for testing peak oxygen uptake. However, WE differed between the two test modalities, meaning that less total energy is used to perform external work of 30 W during wheelchair exercise when using this WCE (VP100 Handisport ergometer). Clinical Trials Protocol Record isNCT00987155/4.2007.2271.

Physiological and Dynamic Responses to Maximal Velocity Wheelchair Ergometry

Eleven male elite wheelchair basketball players took part in an all-out, high-velocity, “Wingate”-type ergometric test lasting 30 s. An electrically braked and electronically controlled roller device was used to measure power and velocity. A breath-by-breath metabolic measurement cart collected net O2 uptake prior to, during, and after the test. Average braking load and velocity were 9.91 N · m and 5.09 m · s-1, respectively. Mean total work during the test was 4,468.47 ± 1,326 J. Based on net O2 cost and estimating a 10% efficiency, the aerobic contribution would be 29.8 ± 10.2%. Therefore, performance in this test seems to be predominantly anaerobic. Velocity variables of the subjects included in this study had a significant relationship to power variables and thus are considered valid for measuring peak performance, mean performance, and fatigue. A regression analysis utilizing wheel size and function as independent variables presented a significant relationship to peak velocity (P <.005). Further findings indicated variability in technique among subjects that led to training suggestions.