I have been thinking recently, inspireed by the efficiency metric, of ways to quantitaltively assess the quality and effect of a set of intervals.
Say I am doing a session of VO2 max intervals at a given wattage. I have played with comparing the efficiency of each interval and monitoring how it declines during the session. Here#s a screenshot from last week:
You can clearly see how the EF drops significantly, by roughly 10% by the time I reach the final interval.
When I repeated the session this week, the result was this:
Does anyone of you have experience with monitoring those numbers over longer periods of time? Do you think they can be used for interval prescription, say by increasing the wattage once the efficincy drop falls below a certain value?
And if we look at an eve bigger picture, do you see value in monitoring efficiency trends over the whole power/duration spectrum to identify areas where more training is needed?
I love this metric and would be very interested to hear your thoughts!
Interesting idea using efficiency for intervals like that. There is quite a bit of stuff in Intervals.icu tracking the related power/HR metric for Z2 riding and you can also look at your power/HR curve for any time period on the compare page. That gives good insight into how you are doing on the PDC.
So intead of power on the y-axis, there would be EF and the filters can be used as they are now to filter only similar intervals. This way, very specific efficiency can be monitored.
I drew an ugly illustration in paint to show the concept. One can see how over last winter, SS/Threshold intervals got more and more efficient. Now, for comparison, my form has dropped.
I would think it’s not very useful in this case of prescription. It is great to look at the drift over long steady state to see where supply and demand are in equilibrium. For these 4min intervals, where multiple sources of energy substrate are required… probably not.
What is the purpose of VO2 intervals? To increase the supply of energy or efficiency of delivery of energy to working muscles, ie spending time at high heart rates and high ventilation rates. Find a way to maximize this time and your capacity will increase.
Looking at your intervals, do you notice you don’t hit 175bpm until the end of second round. That means for 16 minutes of very intense work your heart was only pumping above 175 bpm for 2-3 minutes total. There are better uses of time IMO. Shorter intervals at higher power with less rest eg 1.5:1 up to 2 will bump your cardiopulmonary system up to the max and rely less on glycolysis (longer recovery periods). Using myoglobin is key!
