There is some great information on sprinting in this thread, but another to throw out there is in regards to separation. If you are looking to establish a break and get separation what type of effort are you putting in? I've been working on roughly a 30 second effort at not quite maximum effort and then trying to settle in, but wondering what others are doing to get a gap if you intend to make it stick. In training a good workout I've been trying is 30" sprint followed by 4' @ 90-95% FTP followed by another 30" sprint.