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S G Coleman

Publications and source records attributed to S G Coleman.

15 recordsLinked to original sources

The effect of different calculation methods of flywheel parameters on the Wingate Anaerobic Test.

Researchers compared different methods of calculating kinetic parameters of friction-braked cycle ergometers, and the subsequent effects on calculating power outputs in the Wingate Anaerobic Test (WAnT). Three methods of determining flywheel moment of inertia and frictional torque were investigated, requiring "run-down" tests and segmental geometry. Parameters were used to calculate corrected power outputs from 10 males in a 30-s WAnT against a load related to body mass (0.075 kg.kg-1). Wingate Indices of maximum (5 s) power, work, and fatigue index were also compared. Significant differences were found between uncorrected and corrected power outputs and between correction methods (p < .05). The same finding was evident for all Wingate Indices (p < .05). Results suggest that WAnT must be corrected to give true power outputs and that choosing an appropriate correction calculation is important. Determining flywheel moment of inertia and frictional torque using unloaded run-down tests is recommended.

Acceleration↗

A three-dimensional cinematographical analysis of the volleyball spike.

The objectives of this study were to describe the volleyball spiking actions used by players in top-level competition, and also to examine the interrelationships between upper limb, lower limb and whole body kinematic variables, and post-impact ball speed in the spiking technique. Two Photosonics Biomechanics 500 cine-cameras operating at a nominal frame rate of 100 Hz were used to film the spiking actions of 10 male senior international volleyball players at the XVI Universiade (1991 World Student Games). Three-dimensional object space co-ordinates of digitized image co-ordinates were obtained using a DLT algorithm and an array of calibration points in the filmed volume. Relationships between lower limb angular kinematics at take-off, centre of mass vertical velocity at take-off and centre of mass vertical displacement (jump height) were examined. Relationships between angular kinematics of the hitting arm and post-impact ball speed were also determined. The mean (+/- S.E.) centre of mass vertical velocity at take-off was 3.59 +/- 0.05 m s-1 and the mean height jumped was 0.62 +/- 0.02 m. As expected, a significant correlation was found between the square of the centre of mass vertical velocity at take-off and jump height (r = 0.78; P < 0.01). No significant correlations were found between lower limb angular kinematics and centre of mass vertical velocity at take-off or jump height. The mean post-impact ball speed was 27.0 +/- 0.9 m s-1, and this was significantly correlated to maximum right humerus angular velocity (r = 0.75; P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Ankle Joint↗

Nilutamide. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in prostate cancer.

Nilutamide is a nonsteroidal antiandrogen with affinity for androgen receptors but not for progestogen, estrogen, or glucocorticoid receptors. Consequently, nilutamide blocks the action of androgens of adrenal and testicular origin which stimulate the growth of normal and cancerous prostatic tissue. Nilutamide has a long half-life which permits once-daily administration. Nilutamide is usually given in combination with surgical or chemical castration using gonadotrophin-releasing hormone (GnRH) [luteinising hormone-releasing hormone (LHRH)] agonists. In castrated patients the addition of nilutamide improves objective response rates, bone pain, urinary symptoms, tumour markers and time to disease progression. The tolerance of nilutamide is generally acceptable. Adverse effects are usually mild and reversible and consistent with androgen depletion. Unexpected but reversible adverse effects of nilutamide include delayed adaption to dark after exposure to bright light, transient increases in transaminases, and more severe but rare interstitial pneumonitis. Thus, nilutamide is a welcome treatment option that may be particularly useful in patients to whom the convenience of once-daily administration is seen as a worthwhile benefit.

Aged↗