PURPOSE: To effectively execute the practice of a swimming race by providing a pace maker operating means to light up a single light at a lighting-up part of a lighting-up indicator in a pool and move the lighting-up light successively based on pace data prepared by a pace data preparing means.

CONSTITUTION: A CPU, when a swimmer swims actually a certain distance in a pool, executes the processing to measure the passing time of the swimmer for a constant distance from a start based on program data stored in a ROM, and prepare the pace data from the measured time, and executes the processing to light up a single light at a lighting-up part 12 of a lighting-up indicator 1 in the pool and move successively the lighting-up light based on the prepared pace data. The RAM which can be read and written at any time stores the data such as a swimming distance, time shortening ratio and swimmer individual code inputted from a keyboard, etc., and the prepared pace data. A trainee swims and executes the practice while the trainee watches the light of the lighting-up part 12 to move based on the time data.