It was fairly short discussion, and my take-away is that she simply made the case that if you are over 40 then focusing more attention on hard/explosive efforts offers a better training ROI vs sweet spot.
My interpretation of the science is:
- do as much low-intensity aerobic as possible, because endurance performance scales with volume
- from a recovery point-of-view you have a limited weekly budget for doing medium/hard work
- after 40 the aging process is working to decrease explosive power (fast twitch muscle loss) and max aerobic capacity
- specificity supports doing medium efforts at appropriate times
- in general you will see better performance by focusing training on combining volume with a couple hard/explosive efforts per week.
In other words, high-intensity work is the best antidote for age related declines in performance.
And I believe that aligns with Melanie’s point. Its not “don’t do sweet spot” its “do more high-intensity work.”