The Effects of Rear-Wheel Camber on Maximal Effort Mobility Performance in Wheelchair Athletes

Transcription

1 Taining & Testing 199 The Effects of Rea-Wheel Cambe on Maximal Effot Mobility Pefomance in Wheelchai Athletes Authos B. Mason 1, L. van de Woude 2, K. Tolfey 1, V. Goosey-Tolfey 1 Affiliations 1 Loughboough Univesity, School of Spot Execise & Health Sciences, The Pete Haison Cente fo Disability Spot, Loughboough, United Kingdom 2 Univesity Medical Cente Goningen, Cente fo Human Movement Sciences, Goningen, Nethelands Key wods wheelchai configuation spots pefomance wheelchai populsion field tests Abstact This study examined the effect of ea-wheel cambe on maximal effot wheelchai mobility pefomance. 14 highly tained wheelchai cout spot athletes pefomed a battey of field tests in 4 standadised cambe settings (15, 18, 20, 24 ) with pefomance analysed using a velocomete. 20 m spint times educed in 18 (5.89 ± 0.47 s, P = 0.011) and 20 cambe (5.93 ± 0.47 s, P = 0.030) compaed with 24 (6.05 ± 0.45 s). Lage effect sizes evealed that 18 cambe enabled geate acceleation ove the fist 2 ( = 0.53, 95 % CI = to 0.239) and 3 ( = 0.59, 95 % CI = to 0.170) pushes compaed with 24. Linea mobility times significantly impoved (P 0.05) in 15 (16.08 ± 0.84 s), 18 (16.06 ± 0.97 s) and 20 (16.22 ± 0.84 s) cambe compaed with 24 (16.62 ± 1.10 s). Although no statistically significant main effect of cambe was evealed, lage effect sizes ( = 0.72, 95 % CI = to 0.250) demonstated that 18 cambe educed times taken to pefom the manoeuvability dill compaed with 15. It was concluded that 18 cambe was the best pefoming setting investigated given its supeio pefomance fo both linea and nonlinea aspects of mobility, wheeas 24 cambe impaied linea pefomance. This was likely to be due to the geate dag foces expeienced. Subsequently, athletes would be ecommended to avoid 24 cambe and young o inexpeienced athletes in paticula may benefit fom selecting 18 as a stating point due to its favouable pefomance fo all aspects of mobility pefomance in the cuent study. accepted afte evision Octobe 14, 2011 Bibliogaphy DOI /s Published online: Decembe 20, 2011 Int J Spots Med 2012; 33: Geog Thieme Velag KG Stuttgat New Yok ISSN Coespondence D. Victoia Goosey-Tolfey Loughboough Univesity School of Spot, Execise & Health Sciences Pete Haison Cente fo Disability Spot Epinal Way Leicesteshie United Kingdom LE11 3TU Tel.: +44/01509/ Fax: +44/01509/ v.l.tolfey@lboo.ac.uk Intoduction Consideable advances in the design of wheelchais used fo the wheelchai cout spots (basketball, ugby and tennis) have taken place ove ecent yeas, lagely because of impovements in technology, which has seen these chais become substantially lighte [1, 12, 27 ]. Specific changes to aeas of the wheelchais configuation have also been noticeable. An incease in the degee of ea-wheel cambe, defined as the angle of the main wheels in elation to the vetical [8, 11 ], has been one of the most pominent developments in configuation [1, 5, 15 ]. Inceasing cambe ceates a wide wheelbase, which is thought to povide the use with impoved stability [22, 23 ]. The wide wheelbase can also povide a geate deal of potection to the hands and finges, which may be of paticula elevance to wheelchai basketball and wheelchai ugby, wheeby contacts with othe wheelchais is a common featue [5, 24, 26 ]. Altenatively a disadvantage of a wide wheelbase is the inceased difficulty uses can expeience when negotiating small gaps [7, 18, 22 ]. This would again have implications fo wheelchai basketball and wheelchai ugby playes, who dependent on thei ole, often need to pick o avoid opposing playes and the width of thei wheelbase can facilitate o hinde the pefomance of these tasks [ 7 ]. Despite these developments and the associated effects of inceasing cambe and its wide wheelbase, vey little is known about the influence of cambe on aspects of mobility pefomance specific to the cout spots [ 6 ]. This is due to the focus of pevious cambe eseach having cented pedominantly on daily life populsive conditions [2, 18, 26 ]. A ecent qualitative investigation evealed that highly expeienced wheelchai athletes unanimously epoted that inceased cambe led to impoved manoeuvability pefomance, yet its impact on aspects of linea pefomance yielded mixed esponses [15 ]. Only Faupin and colleagues [6, 7 ] have investigated the effects of cambe on maximal effot mobility pefomance in wheelchai athletes. Examining 9, 12 and 15 cambe Mason B et al. The Effects of Rea Int J Spots Med 2012; 33:

2 200 Taining & Testing settings, Faupin et al. [ 7 ] evealed a negative elationship between inceasing cambe and linea pefomance, as demonstated by lowe mean velocities duing an 8 s spint on a olle egomete. Altenatively, an ealie study by Faupin and colleagues [ 6 ] ove the same ange of cambe settings evealed that 15 cambe impoved tuning pefomance without influencing linea pefomance duing ove-gound populsion. Although the wok of Faupin and colleagues [6, 7 ] has focused on the mobility pefomance of wheelchai athletes duing maximal effot tasks, limitations ae still appaent. In ode to establish eliable cause and effect elationships between the effects of cambe on mobility pefomance, stict standadisation methods need to be imposed to contol fo the knock-on effects that cambe adjustments can have on othe aeas of wheelchai configuation [ 16 ]. Unfotunately, changes in the positioning of the shoulde in elation to top dead cente (TDC) of the wheels wee not accounted fo by Faupin et al. [ 7 ] due to the use of fixed seat heights. In addition to this, the cambe settings investigated wee also not epesentative of the 15 to 24 ange that is commonly used in cout spots today [ 15 ]. Only ecent wok fom ou laboatoy has investigated the effects of standadised cambe settings eflective of those used in the wheelchai cout spots [ 16 ]. It was evealed that inceasing cambe inceased the dag foce and mean powe output expeienced duing submaximal wheelchai populsion. This esulted in an inceased cadioespiatoy demand and a modified populsion technique of wheelchai athletes in the 24 cambe setting [ 16 ]. Howeve, the effect that this ange of cambe settings can have on aspects of mobility pefomance specific to wheelchai spots in a field envionment emains unknown. This study examined the effects of ea-wheel cambe on spotspecific mobility pefomance in highly tained wheelchai athletes. It was hypothesised that inceasing cambe may lead to deceased linea pefomance, especially fo 24, given the geate dag foces associated with this setting [ 16 ]. An impovement in manoeuvability pefomance was also hypothesised with inceasing cambe based on pevious tends [ 6 ]. Methods Paticipants 14 highly tained wheelchai athletes (age 23 ± 6 yeas, mass 66.9 ± 14.3 kg) competing in wheelchai basketball ( N = 11) o wheelchai tennis ( N = 3) volunteeed to paticipate in the study having peviously paticipated in a laboatoy based cambe study [ 16 ]. Paticipants impaiments anged fom lowe limb amputees to spinal cod injuies no highe than a T9 complete lesion. Appoval fo the pocedues involved was obtained fom Loughboough Univesity s Ethical Committee and all paticipants povided thei witten infomed consent pio to testing. This study was also pefomed in accodance with the ethical standads of the Intenational Jounal of Spots Medicine [ 9 ]. Equipment Paticipants wee tested in an adjustable spots wheelchai (Top End Tansfome, Invacae: mass 11.6 kg, wheel size m, tye pessue 120 psi) unde 4 standadised cambe settings (15, 18, 20, 24 ). Standadisation was achieved acoss cambe settings by: 1) Contolling the distance between TDC of both wheels (0.48 m). 2) Contolling the degee of toe-in toe-out though the use of alignment gauges (RGK Wheelchais, Cannock, UK). 3) Replicating the seat height of each paticipant s cuent spots wheelchai in the adjustable wheelchai by using the elbow angle elicited when the hands wee placed on TDC of the wheel, then maintaining this elbow angle between cambe settings by making mino adjustments to the seat height. A velocomete sampling at 200 Hz was attached to the wheelchai thoughout testing, as descibed by Moss et al. [ 17 ]. This enabled the inta push pofiles duing ove-gound manual wheelchai populsion to be collected fo each cambe setting. Wieless timing gates (Bowe, Utah, USA) wee used to ecod the times taken to pefom each of the field tests descibed late. Expeimental design Paticipants pefomed a battey of field tests that compised of 3 dills incopoating movement s specific to the wheelchai cout spots in a spots hall with wooden spung flooing in each cambe setting. The following dills wee completed on the same day, in the same ode, yet the ode of the cambe conditions was andomised: 20 m spint This dill equied paticipants to spint maximally fom a standstill and was designed to assess both initial acceleation and spinting pefomance. Pefomance was assessed by the times taken to pefom the dill and the peak velocities eached. Acceleations wee calculated ove the fist 2 and 3 pushes. Mean velocities, numbe of pushes and the mean deceleations in between pushes wee also deived fom the velocomete taces. Linea mobility Repeated bouts of acceleation, baking and backwads pulling manoeuves wee pefomed duing this dill. A total of 3 incemental distance spint phases wee pefomed duing fowads populsion (5, 7.5 and 12.5 m). Paticipants wee then equied to stop shaply at the end of the fist 2 spints, pio to backwads pulling ove a constant distance of 2.5 m at 2 points ( Fig.1 ). Pefomance was assessed by the oveall times taken to complete the dill. Baking pefomance was assessed afte 5 and 7.5 m of fowads populsion using the deceleation values calculated fom the time at which deceleation commenced until the wheelchai had eached a standstill at point a and b in Fig. 1. The mean and peak velocities exhibited duing each phase of the spints wee also analysed fom the velocomete taces. Manoeuvability This dill was adapted fom Mason et al. [ 14 ] and was divided into 2 sections to assess both spinting and manoeuvability pefomance, as detemined by the times taken. The fist section allowed linea times to be established fo a 9 m spint afte a 5 m olling stat. The second section commenced on completion of this and afte pefoming a shap tun (appoximately 230 ), manoeuvability pefomance was measued by the times taken to pefom a seies of slalom movements ( Fig. 2 ). Paticipants wee instucted to pefom all dills with maximal effot, i. e. as fast as possible. The 20 m spint and linea mobility dill wee pefomed once fo each cambe setting, with the manoeuvability dill epeated twice (once with a left tun at the top and once with a ight tun) with the esultant times Mason B et al. The Effects of Rea Int J Spots Med 2012; 33:

3 Taining & Testing 201 aveaged. Each dill demonstated high levels of within-day eliability, with coefficient of vaiation values anging fom 1.0 % (manoeuvability) to 2.1 % (linea mobility). Paticipants wee familiaised with all the field tests pio to data collection having fequently pefomed these dills duing taining sessions and as pat of a spots science monitoing pogamme. Futhe familiaisation was ensued on the day of testing to allow paticipants to become accustomed to each cambe setting in the adjustable wheelchai. To achieve this, athletes wee equied to pefom each dill in each cambe setting at appoximately % of maximal intensity pio to actual data collection. Each tial commenced when paticipants indicated they wee eady, with a minimum ecovey peiod of 2-min between dills and 15-min between cambe conditions enfoced to ensue that cayove effects such as fatigue did not affect the esults. Fig. 1 Illustation of the linea mobility dill, documenting distances coveed and the movements pefomed. Solid aow epesents fowads populsion and boken aow epesents backwads pulling. Fig. 2 Illustation of the manoeuvability dill. Solid aow epesents linea section and boken aow demonstates agility section of the dill. Statistical analyses Means and standad deviations (SD) wee computed fo all vaiables. The Statistical Package fo Social Sciences (SPPS Vesion 16.0; Chicago, IL, USA) was used fo all statistical analyses. Data was checked fo nomality using Shapio-Wilk tests. Given the paametic chaacteistics of the data, all dependent vaiables wee examined using one-way analysis of vaiance (ANOVA) tests with epeated measues. Since 24 was hypothesised to pefom diffeently to othe cambe settings, simple planned contasts wee conducted as a post-hoc test on significant main effects. Paiwise compaisons with a Tukey LSD post-hoc test established any significant diffeences in pefomance between othe cambe settings. Data was accepted as statistically significant wheeby P Effect sizes and 95 % confidence intevals (95 % CI) wee calculated to detemine the meaningfulness of any paiwise compaisons, wheeby > 0.5 eflected a lage effect [4 ]. Results 20 m spint The esults evealed that cambe affected the time taken to pefom the 20 m spint, with significantly impoved times demonstated in 18 (P = 0.011, = 0.64, 95 % CI = to 0.280) and 20 to (P = 0.030, = 0.56, 95 % CI = to 0.229) compaed with 24 to cambe ( Table 1 ). As a esult the mean velocities achieved duing the 20 m spint wee also significantly highe in both 18 (P = 0.009, = 0.65, 95 % CI = to 0.027) and 20 (P = 0.026, = 0.57, 95 % CI = to 0.010) than 24. No statistically significant main effect was obseved between cambe and acceleation pefomance. Howeve, lage effect sizes implied that a meaningful diffeence existed between the 18 and 24 settings fo acceleation ove the fist 2 ( = 0.53, 95 % CI = to 0.239) and 3 ( = 0.59, 95 % CI = to 0.170) pushes. The main effect of cambe on the mean deceleations between pushes appoached statistical significance, with lage effect sizes demonstating a geate ate of deceleation in 24 than 15 ( = 0.51, 95 % CI = to 0.696), 18 ( = 0.76, to 1.068) and 20 ( = 0.89, 95 % CI = to 1.076). No significant main effect of cambe was evealed fo the peak velocities achieved o the numbe of pushes pefomed duing the 20 m spint, although lage effect sizes demonstated a eduction in pushes fo 18 compaed with 24 ( = 0.60, 95 % CI = to 0.916). Linea mobility As demonstated in Table 2, cambe affected the times taken to pefom the linea mobility dill. Times wee significantly inceased in 24 cambe compaed with 15 (P = 0.010, = 0.64, 95 % CI = to 0.924), 18 (P = 0.003, = 0.72, 95 % CI = to 0.888) and 20 (P = 0.048, = 0.52, 95 % CI = to 0.787). P-value time (s) (0.47) 5.89 (0.47)* 5.93 (0.47)* 6.05 (0.45) mean velocity (m s 1 ) (0.27) 3.42 (0.28)* 3.39 (0.28)* 3.32 (0.25) peak velocity (m s 1 ) (0.47) 4.46 (0.47) 4.53 (0.51) 4.48 (0.53) acceleation ove fist 2 pushes (m s 2 ) (0.43) 2.19 (0.52) 2.12 (0.28) 2.07 (0.52) acceleation ove fist 3 pushes (m s 2 ) (0.37) 1.84 (0.37) 1.81 (0.24) 1.75 (0.36) mean deceleations between pushes (m s 2 ) (1.51) 4.56 (1.95) 4.37 (1.96) 4.95 (1.94) numbe of pushes (1.7) 12.2 (1.8) 12.4 (1.5) 12.7 (1.6) *epesents a significant diffeence compaed to 24 cambe epesents a lage effect with 24 cambe Table 1 Mean (± SD) values fo the pefomance paametes assessed duing the 20 m spint. Mason B et al. The Effects of Rea Int J Spots Med 2012; 33:

4 202 Taining & Testing Table 2 highlights some of the specific aeas whee time was likely to have been lost in the 24 setting. It was evealed that the mean velocities achieved duing the 1 st and 3 d fowads spint phases was significantly geate in 15 and 18 compaed with 24 cambe (P- 0.05, = 0.53 to 0.60). Although the mean velocities eached duing the 2 nd spint phase did not each statistical significance, P-values appoached significance and a lage effect existed between the 18 and 24 settings ( = 0.54, 95 % CI = to 0.042). The peak velocities duing each of the fowad spint phases, o baking pefomance at the end of the fist 2 phases wee not significantly affected by cambe eithe ( Table 2 ). Although, no significant diffeence existed fo the mean o peak velocities achieved duing the backwads populsion phases, a lage effect was established fo 15 to pemit highe mean velocities than 24 ( = 0.61, 95 % CI = to 0.041). Manoeuvability No statistically significant diffeences in manoeuvability pefomance wee evealed between cambe and pefomance duing any section of the manoeuvability dill ( Table 3 ). Howeve, lage effect sizes wee evealed fo 18 cambe to educe the times taken to pefom the linea section of the dill compaed with 24 ( = 0.63, 95 % CI = to 0.082). The 18 setting also displayed lage effect sizes fo a eduction in agility section ( = 0.69, 95 % CI = to 0.220) and oveall times ( = 0.72, 95 % CI = to 0.250) compaed with the 15 setting. The mean values fo both these sections also suggested that a eduction in agility ( = 0.44, 95 % CI = to 0.461) and oveall times ( = 0.41, 95 % CI = to 0.493) occued in 20 compaed with 15, howeve, only modeate effect sizes wee evealed. Discussion The esults of this investigation somewhat suppoted the hypothesis that inceasing cambe anging fom 15 to 24 would negatively affect aspects of linea pefomance. Howeve, the hypothesis that inceasing cambe would impove non-linea pefomance could not be suppoted. Linea pefomance was impaied in 24 cambe given the inceased time taken to complete the 20 m spint compaed with the 18 and 20 settings and the linea mobility dill compaed with the 15 and 18 settings. Subsequently, educed mean velocities wee also obseved duing fowads linea populsion in 24 cambe. A combination of deceased initial acceleation and geate deceleations in between pushes due to geate olling dag foces contibuted to the esticted linea pefomance in 24. Limited statistically significant diffeences wee evident thoughout, yet lage effect sizes and confidence intevals failing to span zeo wee fequently identified and the epoting of effect sizes when intepeting the pefomance of elite athletes in paticula has been advocated [10, 20 ]. Acceleation pefomance was negatively affected ove the fist 2 and 3 pushes in 24 cambe compaed with 18. The mean velocities eached duing the fowads populsion phases of the linea mobility dill wee also geate fo 18 and 15 compaed with 24 cambe. Although, initial acceleation was not diectly investigated duing this paticula dill, these esults do imply an impovement in acceleation pefomance given the highe velocities eached when spinting fom a standstill ove elatively shot distances. The impaied acceleation pefomance obseved fo 24 cambe ae assumed to be the esult of a lage dag foce that has peviously been associated with inceasing cambe [7, 16 ]. The geate esistance associated with inceasing cambe also appeaed to have an effect on spinting pefomance, given the geate deceleations between pushes fo 24 cambe vs. all othe settings. These geate ates of deceleation wee likely to be due to the inceased esistance in 24 cambe since they occu duing the ecovey phase when little can be done by the pefome to ovecome the additional esistance. Despite the inceased esistance and ates of deceleation associated with 24 cambe, the peak velocities achieved by paticipants wee not significantly affected by cambe. This may be due to the stength possessed by the highly tained athletes that wee investigated, which may have been sufficient enough to ove- Table 2 Mean ( ± SD) values fo the pefomance paametes assessed duing the linea mobility dill. P-value time (s) (0.84)* (0.97)* (0.84) (1.10) baking afte 5 m (m s 2 ) (0.61) 3.56 (0.86) 3.74 (0.80) 3.52 (0.90) baking afte 7.5 m (m s 2 ) (0.68) 3.37 (0.62) 3.42 (0.75) 3.29 (1.01) peak velocity - 1 st spint (m s 1 ) (0.33) 3.09 (0.34) 3.08 (0.26) 3.13 (0.33) peak velocity - 2 nd spint (m s 1 ) (0.37) 3.50 (0.37) 3.42 (0.27) 3.43 (0.28) peak velocity - 3 d spint (m s 1 ) (0.47) 3.98 (0.43) 3.95 (0.35) 3.95 (0.41) mean velocity - 1 st spint (m s 1 ) (0.15)* 1.72 (0.23)* 1.55 (0.10) 1.60 (0.18) mean velocity - 2 nd spint (m s 1 ) (0.16) 2.09 (0.15) 2.03 (0.12) 1.98 (0.12) mean velocity - 3 d spint (m s 1 ) (0.21)* 2.56 (0.19)* 2.56 (0.13) 2.49 (0.20) peak velocity - backwads populsion (m s 1 ) (0.35) 2.12 (0.29) 2.19 (0.35) 2.11 (0.33) mean velocity - backwads populsion (m s 1 ) (0.14) 1.26 (0.16) 1.25 (0.19) 1.22 (0.14) *epesents a significant diffeence compaed to 24 cambe epesents a lage effect with 24 cambe P-value linea section (s) (0.22) 2.57 (0.22) 2.59 (0.21) 2.62 (0.21) agility section (s) (0.52) 9.18 (0.56) 9.11 (0.58) 9.25 (0.68) oveall (s) (0.67) (0.71) (0.71) (0.82) epesents a lage effect with 18 cambe Table 3 Mean ( ± SD) times fo all sections of the manoeuvability dill. Mason B et al. The Effects of Rea Int J Spots Med 2012; 33:

5 Taining & Testing 203 come the inceased esistance when the wheels wee in motion and speed had been geneated. Howeve, given the pevious findings elating to acceleation pefomance, this was not sufficient enough to ovecome the esistance expeienced fom a standstill. The esults elating to linea mobility pefomance may also suppot the ealie findings of Mason et al. [16 ], wheeby the inceased esistance associated with 24 cambe also had negative effects on the physiological demand of the same paticipants. Given that 24 inceased the ate of deceleation between pushes and also equied a geate numbe of pushes to be pefomed in elation to 18 cambe implies that athletes ae having to wok hade with each push and suppots the pevious association between this setting and educed economy [ 16 ]. This has potentially vital pactical implications fo athletes competing in the wheelchai cout spots, as ove the couse of a game, 24 cambe may tigge an ealie onset of fatigue. It has aleady been shown that wheelchai ugby playes mean velocities and distances coveed significantly deceases duing the second half of competition [ 19 ]. Theefoe, if a wheelchai configued with 24 cambe could potentially acceleate the onset of fatigue and hinde pefomance late on in matches, this could be a valuable piece of infomation to athletes and coaches alike. Backwads populsion and baking pefomance ae also key indicatos of successful mobility pefomance [25 ]. Although physiological evaluations of backwads populsion have been conducted [13, 21 ], the effect of ea-wheel cambe on this aspect of pefomance has neve been investigated. No statistically significant effect of cambe was identified fo backwads populsion, yet lage effect sizes again existed. These evealed that the mean velocity achieved duing backwads populsion deceased in 24 cambe compaed with 15, which may again be the esult of a geate esistance in the fome setting. Altenatively, baking pefomance demonstated no significant o meaningful effect of cambe. The effects of cambe on manoeuvability pefomance did not suppot what was oiginally hypothesised. Based on pevious findings it was anticipated that inceasing cambe would impove manoeuvability pefomance [6 ]. The cuent investigation did expeience simila esults to an extent wheeby lage and modeate effect sizes existed fo 18 and 20 cambe espectively to educe the time taken to pefom the agility section and the oveall time of the manoeuvability dill compaed with 15. Theefoe although incements in cambe did somewhat impove manoeuvability pefomance, no meaningful impovements wee evealed fo selecting cambe in excess of 20. This demonstated that a linea elationship did not exist fo manoeuvability pefomance within the ange of cambe settings investigated, as had peviously been epoted when investigating a educed ange of cambe settings [ 6 ]. Diffeences did exist between the methodologies employed fo assessing manoeuvability pefomance between the cuent investigation and that of Faupin et al. [6 ]. Faupin et al. [6 ] quantified manoeuvability pefomance by the time taken to pivot aound a cone, wheeas the cuent study detemined manoeuvability pefomance by the time taken to pefom a seies of slalom movements to simulate advancing up cout and avoiding opponents. Both of these manoeuves ae impotant to wheelchai basketball mobility pefomance in paticula [ 3 ]. Howeve, the cuent investigation did not exploe the effects of cambe on pivoting pefomance and theefoe it cannot be assumed that 24 cambe may not have been beneficial fo this aspect of manoeuvability pefomance. If in fact a linea elationship did exist between pivoting manoeuvability pefomance, then playes would need to conside which aspect of manoeuvability pefomance was most impotant to thei specific ole on cout, as to which cambe setting may be the most suitable. The fact that the cuent investigation did not identify any linea elationships between cambe and both linea and non-linea measues of pefomance implied that optimal cambe settings existed within the ange that was examined. Although no optimal setting could be eliably established, since not evey cambe setting within this ange was tested, 18 was the best pefoming cambe setting given its supeio pefomance fo each aspect of mobility pefomance compaed to the othe cambe settings investigated. Thee wee stong tendencies fo geate cambe (20 ) to also enable favouable spinting and manoeuvability pefomance and fo educed cambe (15 ) to allow fo favouable acceleation and backwads populsion pefomance. This demonstates that 18 may not be the optimal setting fo all individuals and that athletes need to conside which aea is most impotant to them and thei ole on cout to detemine thei most effective configuation. Howeve, based on the impovements fo all aeas of mobility pefomance, 18 maybe an advisable cambe setting fo young and/o inexpeienced athletes. These athletes, who have not been though the configuation pocess peviously, do not have any pevious infomation to base thei selections on. Cuently this pocess is extemely subjective and athletes make decisions about configuation based upon tial and eo [ 15 ] and theefoe this study should povide some evidence based infomation fo these athletes. What was clea fom the cuent investigation was that 24 was an unfavouable cambe setting since it impaied both spinting and linea mobility pefomance and failed to impove manoeuvability. Fotunately, this cambe setting, although it does exist, is elatively ae in the wheelchai cout spots and is usually only used in wheelchai tennis [15 ]. The cuent investigation povided a novel, yet detailed examination of the effects of a vaiety of spot-specific cambe settings on aeas of mobility pefomance elevant to the wheelchai cout spots. In ode to make findings even moe specific, othe aspects of pefomance including ball handling, stability and use comfot also need to be consideed and to assist each individual athlete in the identification of optimal configuations, futhe eseach would be advised to conside gouping paticipants by cetain physical chaacteistics. As peviously mentioned, one configuation will not be optimal fo all individuals and factos including classification, sitting height and physical powe have been suggested to influence cambe selection [15 ]. Although gouping paticipants by such citeia would impove the specificity of the esults a substantial sample size would be equied in ode to achieve this without diminishing the statistical powe of the investigation. When investigating elite wheelchai spotsmen/women this can be a challenge given the limited size of this population. One potential limitation with the cuent investigation may aise fom each athlete aleady having a self-selected cambe setting and subsequently a slight bias may be intoduced. A common solution to this poblem is to investigate able-bodied paticipants who do not have a selfselected configuation. Howeve, this appoach is not valid when attempting to exploe the effects of cambe in highly tained wheelchai athletes. Futue studies may altenatively be advised Mason B et al. The Effects of Rea Int J Spots Med 2012; 33:

6 204 Taining & Testing to intoduce an extended familiaisation peiod with each cambe setting pio to data collection, although it is acknowledged that this again may be challenging. Conclusions The cuent study evealed that 24 cambe had negative effects on aspects of linea mobility pefomance specific to the wheelchai cout spots and that 15 cambe had a negative impact on manoeuvability pefomance. The 18 setting pefomed favouably fo all aspects of linea and non-linea mobility pefomance in compaison to the othe settings investigated. As such, 18 cambe may be an advisable setting, paticulaly fo young o inexpeienced athletes who have no pio infomation to base thei selections on. Acknowledgements The authos would like to thank UK Spot fo thei assistance in the funding of this poject though the Gaduate Innovation Pogamme, the suppot of the Geat Bitain Wheelchai Basketball Association and to the athletes who volunteeed to paticipate. Thanks must also go to John Lenton and Pete Cauthes fo thei technical suppot. Refeences 1 Adigo L P, Goosey-Tolfey VL, Minetti AE. Biomechanics and enegetics of basketball wheelchais evolution. Int J Spots Med 2005 ; 26 : Buckley S M, Bhambhani YN. T h e effects of wheelchai cambe on physiological and peceptual esponses in younge and olde men. Adapt Phys Activ Q 1998 ; 15 : Basile F M, Hedick BN. The elationship of skills of elite wheelchai basketball competitos to the intenational functional classification system. The Rec J 1996 ; 30 : Cohen J. A powe pime. Psychol Bull 1992 ; 112 : Coope R A. Wheelchai Selection and Configuation. New Yok : Demos Medical Publishing, Faupin A, Campillo P, Weissland T, Micallef JP. T he effect of the wheel cambe of a wheelchai on the linea speed and on the speed of tuning of the basketball playe. Cinesiologie 2002 ; 201 : Faupin A, Campillo P, Weissland T, Goce P, Thevenon A. T h e effects of ea wheel cambe on the mechanical paametes duing the wheelchai spinting of handibasketball athletes. J Rehabil Res Dev 2004 ; 41 : Fank T G, Abel EW. Dag foces in wheelchais. In: van de Woude LH V, Meijs PJ M, van de Ginten B A, de Boe Y A. (eds.). Egonomics of Manual Wheelchai Populsion: State of the At. Amstedam : IOS Pess, 1993 ; Haiss D J, Atkinson G. Update Ethical Standads in Spot and Execise Science Reseach. Int J Spots Med 2011 ; 32 : Hopkins W G, Hawley JA, Buke LM. Design and analysis of eseach on spot pefomance enhancement. Med Sci Spots Exec 1999 ; 31 : Higgs C. An analysis of acing wheelchais used at the 1980 Olympic games fo the disabled. Res Q Exec Spot 1983 ; 54 : LaMee T J, Labanowich S. The histoy of spots wheelchais pat I: The development of the basketball wheelchai. Spots n Spokes 1984 ; 9 : Linden A L, Holland GJ, Loy SF, Vincent WJ. A physiological compaison of fowad vs evese wheelchai egomety. Med Sci Spots Exec 1993 ; 25 : Mason B S, van de Woude LHV, Goosey-Tolfey VL. T h e i nfluence of glove type on mobility pefomance fo wheelchai ugby playes. Am J Phys Med Rehabil 2009 ; 88 : Mason B S, Pocellato L, van de Woude LHV, Goosey-Tolfey VL. A qualitative examination of wheelchai configuation fo optimal mobility pefomance in wheelchai spots: a pilot study. J Rehabil Med 2010 ; 42 : Mason B S, van de Woude LHV, de Goot S, Goosey-Tolfey V L. T h e effects of cambe on the egonomics of populsion in wheelchai athletes. Med Sci Spots Exec 2011 ; 43 : Moss A D, Fowle NE, Tolfey VL. A telemety-based velocomete to measue wheelchai velocity. J Biomech 36 : Pedios A, Sawatzky BJ, Sheel AW. Effects of cambe on wheeling efficiency in the expeienced and inexpeienced wheelchai use. J Rehabil Res Dev 2007 ; 44 : Sao K J, Misuta MS, Bukett B, Malone LA, Baos RML. Ta ck i ng o f wheelchai ugby playes in the 2008 Demolition Deby final. J Spots Sci 2010 ; 28 : Speed H D, Andesen MB. What execise and spot scientists don t undestand. J Sci Med Spot 2000 ; 3 : Salvi F J, Hoffman MD, Sabhawal S, Cliffod PS. Physiologic compaison of fowad and evese wheelchai populsion. Ach Phys Med Rehabil 1998 ; 79 : Tudel G, Kiby RL, Bell AC. Mechanical effects of ea wheel cambe on wheelchais. Assist Technol 1995 ; 7 : Tudel G, Kiby RL, Ackoyd-Stolaz SA, Kikland S. Effects of ea-wheel cambe on wheelchai stability. Ach Phys Med Rehabil 1997 ; 78 : van de Woude LHV, Veege HEJ, Dallmeije AJ, Janssen TW, Rozendaal L A. Biomechanics and physiology in active manual wheelchai populsion. Med Eng Phys 2001 ; 23 : Vanlandewijck Y, Theisen D, Daly D. Wheelchai populsion biomechanics: implications fo wheelchai spots. Spots Med 2001 ; 31 : Veege D, van de Woude LHV, Rozendal RH. T h e effect of ea wheel cambe in manual wheelchai populsion. J Rehabil Res Dev 1989 ; 26 : Yilla A B. Anatomy of the spots wheelchai. Athlet The Today 2004 ; 9 : Mason B et al. The Effects of Rea Int J Spots Med 2012; 33: