I don’t know but speed is distance over time. acceleration is distance over time squared. Speed work to me is anything that produces a time that is race pace or faster. Bungees, plyos, treadmill overspeed, etc.. i consider drills for motor learning not actual speed work. Power is a measurement derived from acceleration it is the rate at which work is being done. Work is weight over distance, or the case of weights it is weight times number of reps.
How in the world is a 20m thru 50m sprint considered speed endurance?