The classic 7/3 Repeaters are a typical strength endurance training protocol, designed to mimic the grip and relax sequence that is characteristic of climbing. The loads used are generally low, compared to the Eva López MaxHangs protocol, or to the Eric Hörst’s “7-53” protocol, which makes Repeaters safer for intermediate climbers. The rest times between hangs are on the other hand very short, typically just 3 seconds, which stimulates the anaerobic lactic energy system and inevitably leads to severe muscle pump. While Eric Hörst doesn’t consider repeaters to be the best strength endurance protocol, he still thinks it can be useful as a pre-season preparation for lead climbers.