title: Effect of holding a racket on propulsion technique of wheelchair tennis players.
abstract: The purpose of this study was to determine possible differences in propulsion technique between propelling the wheelchair with and without a racket in the hand. Eight experienced wheelchair tennis players performed three submaximal exercise tests and six sprint tests on a wheelchair ergometer. Torque and velocity were measured during the tests and power output and timing variables were calculated. Differences between the conditions with and without racket were analyzed. When propelling with the racket, the racket side showed a significantly lower push time (P = 0.03), lower percentage push time (P = 0.001), shorter contact angle (P < 0.001), more power loss before (P = 0.006) and after (P = 0.001) the push, a higher peak (P = 0.009) and mean (P = 0.005) power output during the push, and a lower mean overall velocity (P = 0.03). When the same hand is compared when propelling with and without racket or when the sprint data were analyzed, similar significant differences were found. Propelling the wheelchair while holding a racket has negative effects on the propulsion technique and may lead to injuries of the upper extremity. The longer time needed to couple the hand with the racket to the rim leads to higher power losses and subsequently higher power output generation during the shorter push phase.
authors.affiliation: Amsterdam Rehabilitation Research Center|Reade, Amsterdam, the Netherlands.|University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, the Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: de Groot
authors.affiliation: Human Kinetic Technology, The Hague University of Applied Sciences, the Hague, the Netherlands.|Faculty of Human Movement Sciences, VU University, Amsterdam, the Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Bos
authors.affiliation: Human Kinetic Technology, The Hague University of Applied Sciences, the Hague, the Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Koopman
authors.affiliation: Royal Dutch Lawn Tennis Association, Amersfoort, the Netherlands.
authors.forename: A E
authors.initials: AE
authors.lastname: Hoekstra
authors.affiliation: University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, the Netherlands.
authors.forename: R J K
authors.initials: RJK
authors.lastname: Vegter
mesh_terms: D000293:Adolescent; D000328:Adult; D001132:Arm; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D016552:Ergometry; D005080:Exercise Test; D005260:Female; D006225:Hand; D006801:Humans; D008297:Male; D019876:Sports Equipment; D013715:Tennis; D019415:Torque; D014910:Wheelchairs; D055815:Young Adult
keywords: Wheelchair tennis; disability sport; hand rim wheelchair; task performance and analysis; torque