A key point stressed during instructor training is to keep the gaps short between tracks. Generally, you want 60- to 90-seconds - just long enough to stretch, change weights, demo the next motion, and get the next song queued up. Not only does this keep the class moving (and on time!), it also ensures that everyone's heart rate stays up, and muscles stay warm.

Every once in awhile, we like to push that envelope just a bit with our "accelerator class". It's when we cut the breaks down even further, to about 15-20 seconds - just long enough for the stretch. And, as a bonus, we sometimes toss in a second ab track to take up the extra five or so minutes we've gained at the end of class. Since the weight changes are done extremely fast, and there's no time for demo, it's a format that should only done with a room full of regulars - never when there's newcomers. It's an exciting change of pace, and we often get requests for it!