“Effective Reps”

Ok so here’s some nerdy “food-for-thought” on the topic of “Effective Reps”, based on the latest evidence.

The Refalo et al., (2024) study has given us a lot of material to think about, in some ways confirming previous research and theories, while in other ways challenging them… overall spicing things up and making things even more interesting!

Interestingly, it has given us some more information about the nuanced topic of proximity to failure and hypertrophy, reinforcing the previous findings of the recent Meta-Regression. (Robinson et al., 2023)

Indeed, training to (or close to failure) is strictly related to muscle growth, but *how close to failure* has been up a topic of debate. On one end, we have the idea that approximately 5 reps from failure are “effective”, and therefore reaching failure maximizes the hypertrophic stimulus of a given set.

And this makes sense: at approximately ~5RM there’s theoretically maximal recruitment of the muscle fibers, especially the type II fibers which are known to grow the most in response to resistance training. Couple their recruitment & exposure to mechanical tension, and it’s logical to see how a “5 RM” may maximize the hypertrophic stimulus of a training set.

Yet, it doesn’t appear to work precisely like that. Mind you, the concept is still valid, but it’s the “5 Reps” that may be an over-semplification of the process.

In fact, with this new paper, we have almost identical results in muscle growth when comparing failure to 1-2 RIR groups!

So, how to navigate these conclusions?

In my opinion, the concept as a whole is still valid of course— however—it’s just “more complicated” and “more nuanced” than previously thought.

Overall, training very close and/or to failure remains a good default approach, and that wil likely result in maximizing hypertrophic results.

However, when it comes to “counting” how many effective reps you accumulated, the range is likely more flexible than a precise amount.