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Accurate speed and split-time information on sprinters is crucial in coaching support. Furthermore, speed and stride parameters (i.e. contact time, stride frequency, and stride length) are important in research on the biomechanics of running. Existing speed-tracking systems for sprinting are expensive, unable to support multiple competing athletes, involve a complicated set-up procedure, or are not sufficiently accurate. This paper describes the design, evaluation results, and application scenarios of a novel, practical, and cost-effective light-sensor network system (commissioned at the National Indoor Athletics Centre, Cardiff, UK) that is capable of capturing criterion-comparable split-time information on simultaneously competing sprinters for long- and short-term coaching support and for biomechanics and sports science research purposes. This unique system is specifically designed to support coaching activities on a daily basis. It was also shown that the light-sensor network system can be integrated with other body-attached measurement systems to achieve continuous tracking of position, speed, and stride parameters of a race.

The first experimental evidence is presented for planar–bent isomerism of complexes of the type [L4M2(μ-X)2]. Both the planar and bent forms have been detected for the same composition, [(Ph3P)4Rh2(μ-F)2], with full exclusion of any variation in such factors as the nature of the metal, ligand, counterion, and solvent of co-crystallization. Computationalstudies point to weak C–H···F intramolecular bonding as an additional factor affecting the choice between the planar and bent geometries. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

In this study, the effects of two different hand placement techniques used by gymnasts to perform Tsukahara and Kasamatsu long horse vaults were examined. Selected linear and angular flight descriptors were calculated to determine whether those gymnasts making initial hand contact on the end of the horse gained additional lift, range or rotation when compared to those gymnasts making the more traditional initial hand contact on top of the horse. Three-dimensional cine-film analysis using the Direct Linear Transformation (DLT) was used to obtain data on 17 elite gymnasts competing in the 1991 World Student Games at Sheffield, UK.The gymnasts were divided into two groups according to the techniques used: group E in which the first hand contact was made on the vertical surface of the near end and the second on the top of the horse, and group T in which both hands were placed on top of the horse. The vertical and horizontal motion of each gymnast's mass centre and the somersault rotation during pre-flight (board take-off to horse contact) and post-flight (horse takeoff to ground landing) were determined. The projections of linear displacements of each gymnast's mass centre onto a vertical plane were determined from the three-dimensional mass centre co-ordinates, and somersault angles were calculated using the line joining the midpoints of each gymnast's shoulders and knees. Whole body mass centre linear velocity and somersault angular velocity were determined using quintic splines. A set of four different segmental inertia data sets was used for each gymnast, together with two different digitizing protocols, but these were found not to affect the findings. Comparisons of group mean data indicated that the only substantial differences were associated with landing distance, which was 32% less for group E. This was accounted for by reduced post-flight horizontal velocity and horizontal mass centre positions at post-flight takeoff, which were consistently closer to the Reuther board end of the horse. Although it might be anticipated that the use of an end-contact technique could be beneficial in preventing a gymnast from slipping along the top surface of the horse, this 'blocking' action reduced the gymnasts' linear velocity in post-flight and did not enhance rotation.

In the kinematic and kinetic analysis of human movement, an accurate assessment of the inertial properties of the body segments under investigation is often essential. Statistical and geometric models of the segments of the upper limb were examined to determine their ability to predict the moments of inertia of these segments. The cadaver data of Chandler et al. (1975) were used as the criteria with which computed values were compared. The regression equations of Hinrichs (1985) gave the most accurate results; the geometric models appeared to offer the greatest flexibility.

Previous studies have reported strong correlations between 5-km performance times and maximal oxygen uptake (VO2 max) and also for running speeds equivalent to blood lactate concentrations of 4 mM. However, there is little information on the physiological responses of individuals during races over this distance. Therefore, the aim of the present study was to measure the physiological and metabolic responses of endurance trained male (n = 8) and female (n = 8) runners during a 5-km time trial using an instrumented treadmill. Performance times were 18.±771.27 min for the men and 21.80±1.98 min for the women (P<0.01). The corresponding times on the athletics track were 17.68 + 0.39 min for the men (P<0.05) and 20.70 + 2.16 min for the women (N.S.). During the treadmill time trials, both the men and women were able to utilize approximately 90% VO2 max, 82% FE max, 98% HR max and produce similar concentrations of blood lactate. Although the physiological and metabolic responses of these endurance-trained men and women to 5-km treadmill running were similar, the faster running times recorded by the men in this study were the result of their higher VO2 max values.

Conquer stress with Grete Waitz. Grete Waitz, Sigmund Strømme and Willi Railo, Van Nostrand Reinhold, 1983, viii + 136 pp, £15.45 (hb), ISBN 0 442 292430Biomechanics and medicine in swimming. A.P. Hollander, P.A. Huijing, and G. de Groot (eds), Human Kinetics, Champaign, USA (distributed in the UK by Eddington Hook & Co.), 1983, 384 pp, $31.95 (USA & Canada), $38.25 (elsewhere), ISBN 0 931250 50 1Microcomputing in sport and physical education. D.A. Brodie and J.J. Thornhill, Lepus Books, Wakefield, UK, 1983, 160 pp, £9.95 (hb), ISBN 0 86019 106 0Coaching women's gymnastics. Bill Sands, Human Kinetics Publishers, Inc., Champaign, USA (distributed in the UK by Eddington Hook & Co.), 1984, xvi + 264 pp, $17.95 (hb), ISBN 6 931250 58 7Physiology of the human body. Arthur C. Guyton, Holt-Saunders International Editions, New York, 6th edition 1984, ix + 691 pp, £8.50 (pb), ISBN 4 8337 0200 2Athletic ability and the anatomy of motion. R. Wirhed, Wolfe Medical, London, 1984, 135 pp, £9.95 (hb), ISBN 0 7234 0854 8Exercise and health: The American Academy of Physical Education. H.M. Eckert and H.J. Montoye (eds), Human Kinetics, Champaign, USA (distributed in the UK by Eddington Hook & Co.), 1984, vi + 153 pp, $12 (pb), ISBN 0 931250 56 0Biomechanics of athletic movement. G. Hochmuth, Sportverlag, Berlin, 1984, 171 pp, £8.95 (hb), ISBNB 7147 20577