Workload and energy expenditure during wheelchair propelling

Sprint, agility, strength and endurance capacity in wheelchair basketball players

The aims of the present study were, firstly, to determine the reliability and reproducibility of an agility T-test and Yo-Yo 10 m recovery test; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB) players. 16 WB players (33.06 ± 7.36 years, 71.89 ± 21.71 kg and sitting body height 86.07 ± 6.82 cm) belonging to the national WB league participated in this study. Wheelchair sprint (5 and 20 m without ball, and 5 and 20 m with ball) agility (T-test and pick-up test) strength (handgrip and maximal pass) and endurance (Yo-Yo 10 m recovery test) were performed. T-test and Yo-Yo 10 m recovery test showed good reproducibility values (intraclass correlation coefficient, ICC = 0.74-0.94). The WB players' results in 5 and 20 m sprints without a ball were 1.87 ± 0.21 s and 5.70 ± 0.43 s and with a ball 2.10 ± 0.30 s and 6.59 ± 0.61 s, being better than those reported in the literature. Regarding the pick-up test results (16.05 ± 0.52 s) and maximal pass (8.39 ± 1.77 m), players showed worse values than those obtained in elite players. The main contribution of the present study is the characterization of the physical performance profile of WB players using a field test battery. Furthermore, we demonstrated that the agility T-test and the aerobic Yo-Yo 10 m recovery test are reliable; consequently they may be appropriate instruments for measuring physical fitness in WB.

Physiologic comparison of forward and reverse wheelchair propulsion

OBJECTIVES

Conventional wheelchair propulsion is physiologically demanding because of the small muscle mass that is used and the low mechanical efficiency of the movement. Previous research has suggested that a reverse wheeling technique might be more economical than conventional forward wheeling. The present study sought to compare the physiologic demands of forward and reverse wheeling techniques.

DESIGN

A repeated measures design was used to compare the dependent variables between forward and reverse wheeling techniques in the same subjects.

SETTING

Human exercise research laboratory.

PARTICIPANTS

Ten able-bodied men.

INTERVENTION

Subjects completed graded, discontinuous exercise tests on a wheelchair ergometer, using both forward and reverse wheeling techniques.

MAIN OUTCOME MEASURES

Oxygen uptake (VO2), ventilation (VE), and heart rate were measured during the last 30 seconds of each 3-minute exercise stage. Blood lactate concentration ([La]) and rating of perceived exertion (RPE) were determined immediately after each stage.

RESULTS

Repeated measures analysis of variance demonstrated that VO2, VE, heart rate, [La], and RPE were all significantly greater (p < .05) with reverse wheeling compared with forward wheeling. VO2, values with reverse wheeling averaged 9% higher than forward wheeling at identical power outputs.

CONCLUSIONS

Reverse wheelchair propulsion is physiologically more demanding than conventional forward wheelchair propulsion and does not appear to offer potential for improving the economy of wheelchair propulsion.

Computer-controlled wheelchair ergometer

A new wheelchair ergometer has been designed in which a combination of realistic simulation of wheelchair propulsion--with adjustable parameters for rolling resistance, air drag, wind speed and slope--and force measurement has been realised. The static solution enables the measurement of physiological and kinesiological parameters. All data from force transducers in seat and backrest, torque transducers in the wheels and force transducers in the wheelframes as well as the acquired speed are sampled in a data-acquisition system. An offline curve processor allows the acquired data to be processed with standard or custom-programmed routines. Preliminary results have been added and are discussed.

Performance evaluation of lower extremity disabled people with reference to hand-cranked tricycle propulsion

A study was designed to evaluate physiological cost and work performance of lower extremity disabled people with reference to hand-cranked tricycle propulsion. Eleven volunteers took part in this study. For an average body weight of 39.7 kg, VO2 max (arm cranking) was only 0.777 l/min at STPD. The pulmonary demand and oxygen uptake of the disabled subjects during tricycle propulsion at 8.45 +/- 0.6 km/h corresponded to about 70% of their maximal response; hence, work stress was categorised as heavy. Mechanical efficiency of cranking was best when a hand-rim propulsion system was arranged for two-arm cranking at the heart level of the disabled person and at a cranking pace of 60 rev/min.