title: The physiological and biomechanical effects of forwards and reverse sports wheelchair propulsion.
abstract: OBJECTIVE
  To explore the physiological and biomechanical differences between forwards (FOR) and reverse (REV) sports wheelchair propulsion.
  
  
  METHODS
  Fourteen able-bodied males with previous wheelchair propulsion experience pushed a sports wheelchair on a single-roller ergometer in a FOR and REV direction at three sub-maximal speeds (4, 6, and 8 km/hour). Each trial lasted 3 minutes, and during the final minute physiological and biomechanical measures was collected.
  
  
  RESULTS
  The physiological results revealed that oxygen uptake (1.51 ± 0.29 vs. 1.38 ± 0.26 L/minute, P = 0.005) and heart rate (121 ± 19 vs. 109 ± 14 beats/minute, P < 0.0005) were significantly greater during REV than FOR only during the 8 km/hour trials. From a biomechanical perspective, push frequencies were similar between FOR and REV across all speeds (P > 0.05). However, greater mean resultant forces were applied during FOR (P < 0.0005) at 4 km/hour (66.7 ± 19.5 vs. 49.2 ± 10.3 N), 6 km/hour (90.7 ± 21.9 vs. 65.3 ± 18.6 N), and 8 km/hour (102.5 ± 17.6 vs. 68.7 ± 13.5 N) compared to REV. Alternatively, push times and push angles were significantly lower (P ≤ 0.001) during FOR at each speed.
  
  
  CONCLUSIONS
  The current study demonstrated that at higher speeds physiological demand becomes elevated during REV. This was likely to be associated with an inability to apply sufficient force to the wheels, thus requiring kinematic adaptations in order to maintain constant speeds in REV.
authors.forename: Barry S
authors.initials: BS
authors.lastname: Mason
authors.forename: John P
authors.initials: JP
authors.lastname: Lenton
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Goosey-Tolfrey
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D006801:Humans; D008297:Male; D009038:Motion; D009068:Movement; D010101:Oxygen Consumption; D064846:Sports for Persons with Disabilities / Q000502:physiology*; D014910:Wheelchairs
keywords: Biomechanics; Physiology; Push strategy; Wheelchair sport