Does focusing on the squeeze really build more muscle?

One common piece of advice given within the gym is to focus on the mind-muscle connection when trying to build muscle. Visualise the muscle lengthening, shortening.

This may not be true.

Reading time: 3-5 minutes

Take-aways

1. An external focus/cue is generally best for performance and strength adaptations.

   1. If you’re aiming to gain strength, pick a technical cue or two to focus on during every exercise.

2. There’s extremely little evidence on whether focusing on the mind-muscle connection is better for growth than an external focus. So far, the evidence is mixed.

   1. You can likely pick whatever focus suits you best. If you also have strength goals, an external focus is likely best. If you don’t have strength goals, focusing on the mind-muscle connection is likely an equally good option.

We do have studies looking at the impacts of internal vs external cueing on performance. Internal cueing generally refers to focusing on bodily sensations during a task, whereas external cueing generally refers to focusing on an aspect of the movement itself or the outcome.

Examples of internal vs external cues. Credit

Broadly speaking, external cueing leads to better performance outcomes, which is most relevant to trainees looking to gain strength. However, increases in performance could also lead to a greater stimulus for hypertrophy, making external cueing superior to internal cueing for muscle building.

That said, making the jump from “this acutely increases performance” to “acute increases in performance lead to greater adaptations” is tricky.

Ideally, we would have longitudinal studies comparing the two approaches and measuring muscle growth directly.

Unfortunately, we only have one study, performed by Schoenfeld and colleagues, comparing the effects of internal cueing (“squeeze the muscle”) and external cueing (“get the weight up”) on muscle growth directly.

Participants in both the internal cue and external cue groups performed the exact same training, consisting of barbell curls and leg extensions. Participants were untrained. Muscle growth was measured via muscle thickness of the vastus lateralis, rectus femoris (quadricep muscles) and biceps brachii. Strength was assessed using isometric elbow flexion and knee extension tests. Finally, skeletal muscle mass was also measured before and after the training intervention.

Here’s what they found.

Elbow flexor thickness improvements were significantly better in the mind-muscle connection group than in the external cueing group. No other significant differences were found. However, it’s worth noting that all other improvements leaned in favour of the external cueing group (including quad thicknesses, isometric strength and skeletal muscle mass).

Why?

You can form two interpretations of this study. The first consists in seeing only the significant difference in elbow flexor thickness as meaningful. Therefore, you would conclude that an internal focus/focusing on the mind-muscle connection is best for muscle growth.

As the authors hypothesize, due to differences in how easy it is to purposely activate the musculature of the upper- vs lower-body, differences were only significant in the upper-body. Therefore, if participants were more highly trained, increases in quad thickness could also have been significantly greater in the mind-muscle connection group.

Alternatively, if you look at the findings in their entirety, you’ll note that only one of four measurements of muscle hypertrophy significantly favoured the mind-muscle connection group. Meanwhile, all other hypertrophy and strength measurements (non-significantly) favoured the external focus group.

This is in line with much of the evidence on performance and strength adaptations around internal vs external cueing. It may be that through focusing on the movement, participants were able to increase performance and volume load across a session, which has previously been linked to more muscle growth.

I personally view this study as a wash for muscle growth.

If you’d like to chat about this study, feel free to comment below.

If you’re looking for an expert to handle your training and nutrition for you, check out our coaching services.