Does periodization style affect muscle growth?
A 2017 meta-analysis by Grgic and colleagues analyzed the research comparing the effects of linear periodization and daily undulating periodization on muscle growth. 13 studies met their inclusion criteria, and they analyzed the data 4 different ways.
1) All measures or estimates of muscle growth in all studies.
2) Only direct measures of hypertrophy (e.g. changes in muscle thickness or cross-sectional area).
3) Only indirect measures of hypertrophy (changes in lean mass or fat-free mass).
4) All measure or estimates from studies lasting at least 11 weeks.
They found the periodization style didn’t significantly affect muscle growth in any of the analyses, suggesting a pretty consistent (lack of) effect. In terms of individual study outcomes, there was one study (by Kok and colleagues) with a reasonably large effect in favor of daily undulating periodization, and one study (by Inoue and colleagues) with a reasonably large effect in favor of linear periodization, while the other 11 studies all found fairly small differences between periodization styles.
Click to expand any of the corresponding figures for more info.
This suggests that as long as volume and intensity are equated, periodization style probably doesn’t have much of an impact on muscle growth. It’s there’s a particular periodization model you simply enjoy using, and muscle growth is your primary goal, it’s probably perfectly fine to use. Of note, this meta-analysis only compared linear and daily undulating periodization, but I analyzed all of the periodization literature a couple years ago, and these results seem to generalize to other periodization models (e.g. reverse linear periodization, block periodization, weekly undulating periodization, etc.), or even lack of periodization (non-periodized training seems to produce just as much growth as periodized training does). You can find one-off studies here or there where some periodization model produces more growth than some other model, but they’re the exceptions to the rule.
If you want to read more on the topic, we discussed this meta-analysis in more depth in volume 1, issue 7 of MASS.
