Quick Overview

This 2023 review in the Journal of Strength and Conditioning Research examined what truly drives strength gains. The authors explained that one key stimulus is forceful muscle contraction. They noted that electrically evoked contractions, such as those produced by NMES/EMS, have been shown in research to increase strength over time. The reason is simple: EMS directly activates motor nerves, causing strong muscle contractions even without maximal voluntary effort. In specific situations—especially when heavy lifting is limited—this mechanism may support strength development through repeated high-force stimulation.
How This Research Found EMS Helps: By Creating Forceful Contractions That Drive Strength

Introduction

Welcome to the ORIEMS FIT Research Digest.

Our mission is simple.
We take real university research and explain it in everyday language.
No hype. No promises. Just clear understanding.

This article is for education only.
It is not medical advice.
It does not diagnose, treat, or replace professional care.

Today we look at a 2023 review in the Journal of Strength and Conditioning Research that examined what truly drives strength gains — and how electrically evoked contractions (EMS/NMES) fit into that process.

What Was This Study About?

This was not a single experiment.
It was a narrative review.

That means the authors analyzed and summarized many strength studies to answer one question:

What actually causes strength to increase?

They broke strength development into a chain:

Mental effort → Neural activation → Forceful muscle contraction → Movement → Adaptation

The important part for EMS is here:

Forceful muscle contractions are one of the key drivers of strength gain.

And here is where EMS becomes relevant.

The Specific Way EMS Helped

The review states that electrically evoked contractions — meaning contractions created by electrical stimulation rather than voluntary effort — have been shown to increase strength over time in research.

This is the key mechanism.

EMS/NMES works by:

• Sending electrical signals through motor nerves
• Causing muscle fibers to contract
• Producing strong contractions even without maximal voluntary effort

The authors describe that forceful contractions are a major stimulus for strength adaptation.

So when EMS creates those contractions, it may contribute to strength improvements over time.

Not because it is “magic.”

But because it directly stimulates one of the core drivers of strength:
high-force muscle activation.

Why This Matters

Early strength gains are often neural.

That means improvements happen in:

• How the brain activates muscle
• How efficiently motor units fire
• How strongly fibers contract

EMS bypasses some voluntary pathways and directly activates motor units.

This may:

• Increase motor unit recruitment
• Improve neural drive
• Create contractions when voluntary effort is limited

The review supports the idea that electrically evoked contractions can be associated with strength increases in certain contexts.

Important Context: When It Helps Most

The review is careful.

It does not say EMS replaces lifting.

It does not say EMS is superior.

It notes that:

In healthy individuals already performing heavy resistance training, some forms such as whole-body EMS may add minimal extra benefit beyond proper strength training.

However, EMS may be particularly relevant when:

• Heavy loading is not possible
• There is joint limitation
• There is injury recovery
• Muscle activation is reduced
• Equipment access is limited

In these situations, EMS can still produce strong contractions.

And strong contractions are one of the key stimuli for strength.

What This Means for Someone Considering EMS

EMS may help by:

• Producing forceful contractions
• Stimulating motor units
• Supporting neural activation
• Complementing structured training

It is not a shortcut.

It is not a replacement for progressive overload.

It is not a guarantee.

It is a tool that works through a specific physiological pathway:
forceful contraction stimulus.

What This Means If You Already Use EMS

Consistency matters more than intensity spikes.

Strength adapts to repeated exposure to stimulus.

If using EMS:

• Follow structured programming
• Do not replace proper movement practice
• Allow recovery
• Keep expectations realistic

Strength development is a long process.

EMS may support it by reinforcing one key part of that chain — strong contraction.

Detailed Research Summary Table

Link to original study:

https://journals.lww.com/nsca-jscr/fulltext/2023/04000/maximizing_strength__the_stimuli_and_mediators_of.22.aspx

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Conclusion

This research did not claim EMS is superior.

It did not promise dramatic transformation.

It identified something more fundamental.

Strength increases when muscles experience strong, repeated contractions.

Electrically evoked contractions — created through EMS/NMES — have been shown in research to contribute to that process.

That is the specific way EMS helps.

As always:

Informed decisions are better than emotional ones.

Read the full study.
Understand the mechanism.
Set realistic expectations.

Disclaimer

This article is for educational purposes only.
It is not medical advice, diagnosis, or treatment recommendation.
ORIEMS FIT does not claim to cure, treat, prevent, or manage any disease or medical condition.
Individual results vary.
Research findings may not apply to all individuals.
Consult a qualified healthcare professional before using electrical stimulation if you have a medical condition, implantable device, injury, or concerns.
This content does not replace professional medical care.
ORIEMS FIT is not affiliated with the institutions or authors mentioned.
No guarantee of results is made or implied.
Readers are responsible for their own health decisions.