I have often been asked the question â€˜What does 3 x (3+3) minutes VO2 max mean?Â´ so I thought it would be a good idea to spent a short post on it. 3x(3+3)min VO2 max means 3 times 3 minutes maximal effort with recovery periods of 3 minutes between each interval. (3min hard work, 3min recovery, 3min hard work etc.)
VO2 max refers to the intensity you shall try to maintain through the intervals.
Itâ€™s clear that you donâ€™t know what your actual VO2 is, but when you have tried these intervals a couple of times you will know how to pace yourself.
The important thing to remember is that you are supposed to ride as fast as you can for a period of 3 minutes (but not faster than you can repeat it a couple of times).
It is not possible to use a heart rate monitor for pacing because of the delay of the heart rate but can be a good indicator of your performance afterwards.
A power meter like SRM or PowerTap is very useful for such pacing. Yeah, they are expensive, but strongly recommended if you are a serious cyclist.
In the recovery periods it is a good idea to do some light pedalling to remove metabolites. That will make it easier for you to make the following interval at the right intensity.