The Holyfield one is a myth if you can find an old episode of WBF Bodystars when they did a feature on Evander and they showed his training and one of the things he always did was 5 miles of running each morning, in his words "So as not to get heavy legs like a football player".
Early on in his career he did roadwork. Read this: [url]http://www.sportsci.org/news/news9709/hatfield.html[/url]
I know that. I'm actually a big fan of Dr Hatfields work. he's one of the best trainers around. He works closely with Lee Haney actually ( I think they own a few gyms together). But the programme I'm referring to was aired in 1992, just a wee bit after the Larry Holmes fight. As I recall Holyfield wasn't working with Hatfield anymore and Tim Hallmark had modified his training regimen.
I know Holyfield has said that he does roadwork at different points throughout his career but every coach he's worked with has mentioned how he either doesn't do roadwork or that he dislikes roadwork. I read a fairly recent article on Holyfield and he talks about cycling, swimming and running for his cardio fitness, he also mentions that going for long runs aren't useful for boxing so his definition of roadwork was certainly not the typical definition of roadwork.
Yeah sprints are great when performed in intervals, works the aerobic system as well. Running is about cardio fitness, plenty of things can condition the legs at least as well as running can.
Sprints helps with adding explosiveness, and short rest intervals improves your recovery. The quicker you can recover after an explosive burst the better. The idea for Haye is to be able to explode at any given moment and then recover in quick time to be able to go again. He's been successful with it, is able to punch with the same intensity and speed from round 1 to 12. Buzzed valuev late, and caught wlad with a hard shot and took out ruiz in one of the later rounds. The drawback is though, he can't and won't fight at a sustained pace throughout the fight. But the type of training he does works for the way he fights. He's not a volume puncher, he fights in bursts, so sprints and intervals are perfect for him. What will be interesting though, is that Haye may not have the luxury to fight in bursts because he's going to be pressured, like he was against Ruiz, he had to up his punch volume and you saw him throw more. He will have to do it again against Chisora if he doesn't get him out of there quickly. There are many ways to train though, running being one of them, but road work is not the be and end all for a boxer, you just fit the regimen around yourself, which will complement your style of fighting.