A word on INTENSITY from BodyRock:

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"The reason why I keep my workouts short is because you are supposed to be pushing at your maximum effort. It is simply not possible to sustain this kind of intensity over longer periods of time. Simply put, if you have anything left at the end of these workouts, then you didn’t train hard enough. Everyone has their own level of what max effort means, but the one thing that we should all have in common at the end of these workouts is that we should be completely wiped out. Everything depends on your effort and how much you are prepared to push in these few minutes of training. If you decide to put comfort before intensity then you are trading away your results."

You've heard it from me, and from other leaders in fitness : INTENSITY over TIME.   Look at Insanity, P90X or BodyRock.  The workouts are structured with timed intervals of MAX EFFORT.  No matter ...what workout you choose, this format can work for you- as long as you are honest with yourself about what your MAX EFFORT is.  Make no mistake: it's not a comfortable feeling.

BEGINNERS: If you are just starting a workout routine, then your max effort is going to look very different than a seasoned athlete.  This is where heart-rate monitors are helpful for beginners to measure their efforts.

ADVANCED FITNESS LEVELS: A heart-rate monitor is one more gadget than you need. You know by now what max effort means and feels like.  Think of finish line sprints or the peak of your game or performance (in the case of dancers).   Opt instead for an interval timer or changing up other factors in your routine:  frequency, resistance, length of intervals, etc.

Next time I see you for a session or a class- remember: If you decide to put comfort before intensity, then you are trading away your results.