Extendable spikes for shoes

摘要

Golf shoe sole 10 having extendable spikes 71 activated by compressed air from a pump 42 located inside sole of shoe. Pump 42 is operated by weight of wearer's heel on a bladder 41 located in heel of sole and check valves 51 maintain pressure in pneumatic system. Pushbutton switch 58 selects movement of spikes 71 between retracted and extended modes.