A note in reference to the debate as to whether one may benefit from a weights dominant vs. sprint dominant vs. balanced approach:
Keeping in mind that speed is the ultimate goal the solution must obviously not lose site of this fact.
As it stands, particularly regarding speed as it exists in the zone that precedes maximum velocity (ergo starts and acceleration) there are those whose speed is more rooted in higher force/lower velocity training (ergo higher intensity strength training) those whose speed is more rooted in speed-power work itself and others whose speed is rooted in a balance of the two.
So as others here have eluded to, it is only logical that each individual find, through trial and error, what is optimal for them.
As I discuss in my most recent lecture DVD, one of my fastest and most powerful players (Jonathon Baldwin) does virtually zero strength training for his legs short of a version of pilates with the cables on a shuttle device. His output potential is so high that the stimulus from the speed-power work, and practice of sport itself, is enough for him to further increase his speed-power.
Thus, I only have him strength train his upper body and he continues to sprint faster, jump higher/farther, and throw med balls farther.
Another one of my fastest and most explosive players (Buddy Jackson) performs leg press with moderate loads, never very heavy, along with the speed-power work and he has continued to develop.
Lastly, another one of my most explosive players (Dion Lewis) derives his speed very much from his strength as he very routinely squatted 530 on a safety squat bar this summer at a bodyweight of 188 or so.
So here’s three examples of players who all perform speed-power work who are all comparable in their speed in the range of <30-40yds yet one does no weight training for his legs, another performs moderate weight training, and the other squats the house.
It’s not what many like to hear; however, in order to maximize an athlete’s potential the training must be individualized to that athlete.