PURPOSE: To obtain information on an already swum distance without adding up a pool course length by a method wherein a reference distance corresponding to the pool course length or the like is set in advance and the reference distance is accumulated at every reference time required for swimming.

CONSTITUTION: A mode register in a RAM 14 designates a clock mode, a record mode, a distance mode and the like. An event register sets the event of a swimming competition as an object under test, a distance designation register sets the swimming distance of the swimming competetion, and a distance storage register sets arbitrary distances other than competitions. By operating a switch part 12, the individual registers are set, the switch is operated so as to match the start of a competition, an FF 6 is set to a set state, a signal from a frequency divider circuit 3 is sent to a time measuring circuit 8, and a time measuring operation is started. After the measuring operation has been started, the measured time measured by the circuit 8 is displayed on a display device 15. When the competition has been finished, the RS flip-flop 6 is set to a reset state by operating the switch, and data which has been measured is stored in the RAM 14.