And your questions is a bit not in line with what is being said. I don’t think anyone advocates using IT to the exclusion of SE or special endurance throughout the entire season, but as a way to lead into it or as a way get work in earlier in the year. I don’t think many, even in the int. tempo based programs, have tons of IT leading into their tapers or important competitions, as an example.
you hit the hammer squarely on the head of the nail right here.
If someone is making their athletes do IT in the last 4-5 weeks of the season for HS their athletes most likely will not be worth a damn. With the same thoughts someone making their athletes do speed-endurance at this time of year on a regular basis is not going to see their athletes get better throughout the course of a season. Intensive tempo programs themselves have trouble having athletes improve throughout the course of a season often times because they are over-trained before the taper, but partly because event specific fitness is reaches its peak earlier in the season. How much intensive tempo is needed by short sprinters? Not much, but certainly more than others are willing to give it credit for my athletes do nearly 20k of IT work across 5 months. That’s less than 1k per week average over the season, but far less than what IT based programs do. I think you have to seamlessly blend IT work into Speed and Special endurance sessions. Most coaches I see doing IT work are trying to shorten the rest interval and doing so doesn’t allow for such blending of the types of training together.
If you are worried about the CNS system attach a heart rate monitor to your athletes. HR although autonomic is the best known way to glimpse how the CNS is coping with stress. Do it in all your workouts. If they cannot recover to <90 bpm in accel/maxV work within 6-8 minutes they are fried, if they cannot recover to <100 bpm in 8-10 with speed endurance work they are fried. If they cannot recover to <120 bpm in 4-6 minutes in IT they are fried. All it boils down to is, If your athletes cannot recover in the allotted amount of time given for rest by most texts on accel/maxV, speed end, or IT then your athletes CNS systems are fried because the cumulative amount of stress is causing the body to take longer to recover and not because they are not fit, just they are not fit enough for your workouts.