For years we've known about the benefits of something called "post-activation potentiation." Get warmed up, then do a heavy, low-volume squat or deadlift. Afterward, do a jump or sprint. What happens? Explosive jumping and sprinting performance increases after the heavy lift.
Put another way, loading muscles with high resistance acutely improves explosive muscle action. Heavy helps explosive. But we never look at it the other way.
Research by Masamoto et al. tested this out. They tested the 1RM of several athletes: sometimes they did tuck jumps and drop jumps first; other times they just performed their usual warm-ups first. The result? When they jumped before squatting heavy, they lifted more weight.
Next time you're getting ready for a heavy squat workout, do a few jumps before training. Not only will it develop explosive ability, but it can significantly add poundage to your squat.