You spend hours in the gym moving weights through a full range of motion—squatting, pressing, and pulling. It's the foundation of strength training. But what if I told you that not moving could build just as much, or even more, strength?
A brand new 2025 systematic review and meta-analysis from the Journal of Science and Medicine in Sport put this exact question to the test, comparing traditional dynamic resistance training (DYN-RT) with isometric resistance training (ISO-RT).
Let's break down what the science says and what it means for your training.
A quick note: This review is based on the abstract only, as the full text was not available.
Defining Our Terms: Dynamic vs. Isometric
First, let's get on the same page.
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Dynamic Resistance Training (DYN-RT): This is what most of us think of as lifting. It involves producing force while your joints move through a range of motion. Think of a bicep curl, a squat, or a bench press.
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Isometric Resistance Training (ISO-RT): This involves generating maximum force without any joint movement. Imagine pushing against an immovable wall, holding a heavy weight in a fixed position (like a plank or a wall sit), or pausing a lift mid-rep and holding it.
The long-standing question has been: which one is better for getting strong? This new research gives us the clearest answer yet.
The Study: A High-Level Look at the Evidence
Researchers didn't just run a single experiment. They conducted a meta-analysis, which is a powerful type of study that pools the data from many previous experiments. This gives us a much more reliable conclusion than any single study could.
They analyzed 32 different studies that included a total of 621 healthy adults (aged 18-45). They compared the effects of isometric training against both a non-exercise control group and traditional dynamic training.
They looked at two types of strength:
- Isometric Strength: The maximum force you can produce in a static position.
- Isokinetic Strength: The maximum force you can produce at a constant speed through a range of motion (a good proxy for dynamic strength).
The Main Findings: Isometrics Pack a Punch
When the dust settled, the results were compelling.
First, as expected, isometric training was significantly better than doing nothing. The group performing isometrics saw significant strength gains compared to the control groups (SMD = 0.65).
But here's the kicker: when compared head-to-head, isometric training led to greater overall strength improvements than dynamic training (SMD = 0.35).
This is a huge finding. It suggests that static holds, an often-overlooked training modality, might be a superior tool for strength development. But to understand how to apply this, we need to look at the specifics.
Digging Deeper: Specificity Is King
The researchers broke down the results to see how each training style affected different types of strength. This is where the most practical takeaways are found.
For Building Isometric (Static) Strength
When it came to improving pure isometric strength, isometric training was the clear winner. The analysis showed significantly greater isometric strength gains from ISO-RT compared to DYN-RT (SMD = 0.43).
This makes perfect sense. The principle of specificity dictates that you get good at what you train. If you want to improve your ability to hold a position and resist force—like bracing your core for a heavy deadlift, holding a front rack position, or winning a grappling exchange—isometric training is your best bet.
For Building Isokinetic (Dynamic) Strength
This is the most surprising finding of the entire study. When comparing the gains in isokinetic (moving) strength, there was no statistically significant difference between isometric and dynamic training.
Let that sink in. Training with static holds was just as effective at building strength through a range of motion as training with conventional lifts. This challenges the long-held belief that you must train dynamically to build dynamic strength. It opens up a world of possibilities for how we can structure our programs.
How to Apply This to Your Training
So, should you drop your squats and bench presses in favor of wall sits and static holds? Not so fast. The conclusion isn't that dynamic lifting is useless, but that isometric training is an incredibly powerful and underutilized tool.
Here are some practical ways to incorporate these findings:
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As a Complement, Not a Replacement: Use isometrics to supplement your main lifts. Add in overcoming isometrics (pushing/pulling against an immovable object) or yielding isometrics (holding a weight in place) to strengthen specific positions.
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Bust Through Sticking Points: Are you weak at the bottom of your squat or halfway up your bench press? Program isometric holds at that specific joint angle to build strength right where you need it most.
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A Low-Impact Strength Builder: Isometrics generate high levels of muscular tension with very little stress on the joints. This makes them an excellent option for athletes managing injuries, during deload weeks, or for anyone looking for a joint-friendly way to get stronger.
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Enhance Stability and Bracing: Incorporate exercises like planks, side planks, and paused deadlifts to improve your ability to create and maintain total-body tension, which will carry over to all your other lifts.
The Bottom Line
This 2025 meta-analysis provides strong evidence that isometric training is not just a rehab tool or a beginner's exercise. It is a potent method for building serious strength.
- Isometrics are superior for developing static, position-specific strength.
- Isometrics are just as effective as dynamic lifts for improving strength through a range of motion.
By intelligently adding isometric exercises to your routine, you can tap into a powerful stimulus to bust through plateaus, shore up weak points, and build a new level of strength.
Reference:
Ghayomzadeh M, Li J, Eidy F, Keshavarz M, Sabag A, Fornusek C, Hackett DA. (2025). Effects of isometric vs. dynamic resistance training on isometric and isokinetic muscular strength: A systematic review with meta-analysis. Journal of science and medicine in sport.