Light flicker is caused by the 60 cycle AC power, and lamps that tend to flicker. The light color and brightness modulates with the AC. Most newer clubs, and clubs that upgrade have lights that minimize this problem. The modern way to resolve this is an upgrade to non-dimming LED lighting products. They save energy and last longer than conventional lamps. For a photographer, light flicker is impossible to eliminate when taking action shots (shutter speeds faster than 1/120). It takes careful work in Photoshop to reduce the effects.