Greg Nuckols runs a website called Strength & Science, which I have added to my list of research and science based blogs here on my website. Lots of great info there so be sure to check it out. Of particular interest to me was this article on why DUP was superior to LP and the answer might just surprise you!
Ever since I wrote my article on Daily Undulating Periodization (DUP) a couple months ago, I’ve had a nagging feeling that something wasn’t quite right, like something was a little bit off. (If you haven’t read the first article, or if you don’t know what DUP is, I’d suggest you check it out first)
Physiologically, I’m not sure the rationale behind DUP totally makes sense of the situation. Not that it is entirely nonsensical, but I had a feeling that the effects and benefits couldn’t be explained solely by the physiological mechanisms proposed.
The basic notion is that your body meets a new stressor, and responds strongly to it. The more times it’s exposed to the same stressor, the weaker the reaction to it is. When you give someone similar workouts week-in-and-week-out their body habituates to the stressor, so the rate of adaptation slows down. This is known as the repeated bouts effect. With DUP, since you’re changing the volume and intensity with every training session, you’re not dealing with the exact same stressor all the time, so less habituation takes place, so your body keeps adapting faster. DUP, the theory goes, minimizes the factors contributing to the repeated bouts effect, so you get better gains from it.
That’s the basic theory, and it’s certainly a plausible one. And I certainly believe that it can account for some of the differences observed in the research. However, the more I think about it, the more I’m convinced these physiological differences don’t account for the entirety of the difference, or perhaps even the majority.