Effects of backrest positioning and gear ratio on nondisabled subjects' handcycling sprinting performance and kinematics

Abstract

Abstract-Backrest position is a significant parameter in handcycling that one must consider when seeking to optimize the user-to-chair interface. We studied the effects of backrest position on handcycle propulsion kinematics. Ten nondisabled participants with no handcycle propulsion experience repeated an 8 s sprint with three backrest positions (backrest angle between 45°a nd 50° to the horizontal, backrest angle between 65° and 70° to the horizontal, and without backrest) and three gear ratios (GRs) (GR22/21 = low, GR32/21 = medium, and GR44/21 = high). We used three-dimensional movement analysis to calculate the average maximal velocity, cycle frequency, and angle parameters for the arms and trunk. Our results showed statistically higher trunk flexion/extension (p < 0.001) and maximal velocity (p < 0.001) when a backrest was not used. Moreover, these differences were accentuated as the GR increased (GR44/21). Our results suggest that handcycle users with unimpaired upper-body and trunk function can improve handcycling performance by removing the backrest. Nevertheless, future studies on specific groups of subjects with spinal cord injury should be conducted.

The exercise profile of an ultra-long handcycling race: the Styrkeprøven experience

“…1 The high mechanical efficiency of this geared fixed-frame racing cycle in comparison with an manual wheelchair can potentially increase the distance a person with a loss of lower limb function can travel. 2 To guide the optimal setup for the handcyclist the influence of crank length 3,4 and crank configuration 5,6 have been analyzed. The physiological profile of the handcyclist has also been studied, 7,8 and although this is often limited to investigations within the laboratory environment some studies have explored this relationship in competition.…”

A Biomechanical Analysis of Handcycling: A Case Study

“…At present, very few data concerning the kinematic (Faupin et al, 2004(Faupin et al, , 2006(Faupin et al, , 2008, kinetic (Verellen et al, 2004b), and surface electromyographic (EMG) (DeCoster et al, 1999) parameters of handcycling are available.…”

Effects of type and mode of propulsion on hand-cycling biomechanics in nondisabled subjects

“…Moreover, based on body position on the HC, two types of propulsion exist [24][25]: arm-power (AP) and armtrunk-power (ATP). The sitting position (upright, semirecumbent, kneeled, and bent forward) determines whether the HC is powered with the arms only or with the arms and trunk [26].…”

“…However, only persons with functional trunk muscles and good abdominal strength can use ATP propulsion [25]. We are aware of only one study by Faupin et al that focuses on a kinematics comparison between AP and ATP propulsions [24]. This recent study investigated the effects of backrest position and gear ratio on hand-cycling sprinting performance in 10 nondisabled participants.…”