Training Tips #6: When enough is enough!

Often you go out for a training ride planning to do intervals. But how do you know how many sets of intervals you should be doing? How many sets should you be pushing yourself to gain the most benefits? Or when is it enough to call it a day when another set of intervals won't give you anymore gain?

Below is a rough guideline that will help you decide when enough is enough:

Intervals                      Average Drop in Power
20 mins                       3 - 5%
10 mins                       4 - 6%
5 mins                         5 - 7%
3 mins                         8 - 9%
2 mins                         10 - 12%
1 min                           10 - 12%
30 secs                        12 - 15%
15 secs                        Peak power drops by 15 -20%

Taking note that the percentage drop in average watts is based on the number of watts achieved in the third set of intervals. Since we are assumed to be fresher when we begin doing our intervals, we throw out the first 2 sets of readings and take the third set as the reference instead.

The reason we should stop our interval workout when we hit the average drop in power shown in the guidelines is because we are no longer training intensely enough to elicit enough stress to cause a training improvement or adaptation. Therefore, it is advisable to stop your workout and try again another day as any amount of intervals you do thereafter will not be beneficial in any way.

Likewise, after doing what you set out to do but realised that your average power did not drop above what is stated in the guidelines, that means you could have done more intervals to gain even more training adaptation! Therefore, with the use of a power meter, you are able to figure out the optimal number of training intervals for each workout.


"Train just enough for success" - Joe Friel


Hunter Allen and Andrew Coggan (2010). Training and Racing With A Power Meter. Colorado: VeloPress.