The coordination drills you run before a session. Of all the variants, the B-skip predicts sprint performance most clearly — the A-skip barely at all.
Two or three drills before every session are the cheapest compound interest in track and field — but only if you pick the right ones and execute them cleanly. In a drill test battery the B-skip was by far the strongest predictor of sprint performance (β = −0.531 over 5 m, β = −0.322 over 20 m), while the A-skip came out trivial. Two things follow. First, execution beats volume: knee angle and forefoot contact decide the outcome, not how many skips you rack up. Second, the caveat that every warm-up video skips: the models explained only around 20 to 22 percent of the variance in sprint times. Drills prime coordination, they don't replace actually sprinting. And warm up dynamically — static stretching showed no advantage over no warm-up at all in sprint and jump testing.