Here is a question I've had for some time, maybe someone can answer: In doing maximum intensity intervals of say 3 minutes I start with a heart rate of around 110 or 120 and struggle mightely to bring my heart rate up to 175 or 180 in just 3 minutes, so that only a fraction of the 3 minutes is actually spent at goal. (my maximum ht rate is 186) Naturally after I'm at the third or fourth interval its a bit easier but still only a part of what I'm counting as the 3 minutes is spent near maximum heart rate. Is this correct or should one be spending the whole 3 minutes at goal and not even count the time leading up to it?