Originally Posted by
hamster
I've seen Seiler's article before. The biggest problem I have with this approach is "post hoc ergo propter hoc" logic. Pro athletes train 20 hours/week. They do so because they are pro athletes and they have nothing better to do. I am willing to accept that an athlete who trains 20 hours per week achieves optimal results when he spends 75% of the time in Z1. After all, there's likely diminishing returns to time you spend in higher zones. Question is (the talk alludes to this, but I don't see any evidence in its favor): is it still optimal to spend 75% of time in Z1 if you only train 8 hours a week, or is it optimal to hold Z2/Z3 time constant?
That's a good point. Most of these studies have a selection bias, athletes with naturally high VO2. Don't think there is a magic percentage, it boils down to how well you can recover? Take an 8 hr week, 25% of that is 120 min so that would be 12 x 10m or 24 x 5m intervals spread out over that 7 days. Myself I know that I would be challenged doing 4 really good quality 3x10 workouts in 7 days.
I've tended to hold a constant % of volume as high intensity (15% to 20%), cycling overall volume up and down. Rather than hold my low intensity work volume constant and pile more or less high intensity on top of that. I don't think this needs to be "perfect". As long as you find an approach that lets you recover & keep the quality of your intervals high you are going to get fit and be able to maintain some consistency.