Advances in electronic timing systems: considerations for selecting an appropriate timing system.

The proper selection of equipment is vital to the ability to accurately measure and track changes in performance. When measuring sprint time, electronic timing systems are recommended but may contain significant errors when an arm or leg passes through a gate before the torso. Dual-photocell (DP) and signal processing systems have been developed to overcome these issues. Ten subjects performed 10× 10-m sprints during which split time was calculated using 3 timing systems: a single photocell (SP) and DP without processing and a no-reflector gate with signal processing. The DP had fewer false signals compared with the SP (7, 14); however, signal processing eliminated all false signals. The mean differences between the 3 timing systems ranged from 9 to 17 milliseconds; however, the SD ranged 12-42 milliseconds because of the occurrence of false signals. When performing repeated 10-m sprints, it is vital to have a system that reduces or eliminates the occurrence of false signals, or training adaptations are likely to be overlooked. Thus, for 10-m sprints or splits, a timing system that reduces the incidence of false signals is needed (either DP or gates signal processing), and the use of an SP system without internal processing is inappropriate. However, as the distance and the expected adaptations increase, a smaller proportion of the adaptation is likely to be confounded when using an SP system.