Are you grinding out endless, painful sets of Nordic Hamstring Curls (NHEs), convinced that more volume is the only path to bulletproof hamstrings? It’s a common mindset in the gym: to get stronger, you have to do more. But what if all that extra effort isn't actually leading to better results?
A massive new systematic review and meta-analysis from 2025 is challenging this exact assumption. Researchers dug into 42 different studies to find the real dose-response relationship for the king of hamstring exercises. The results might just save you a lot of time and unnecessary soreness.
Let's break down what they found and what it means for your training.
This article is based on the abstract of the paper, as the full text was not available.
What the Science Says: The Big Picture
First, the good news: the review confirms that the Nordic Hamstring Exercise is incredibly effective. The paper, published in the Journal of Strength and Conditioning Research, pooled data from dozens of studies to get a high-level view of the exercise's impact.
Here’s the performance breakdown:
- Excellent for Eccentric Strength: NHE training produced large and significant improvements in eccentric strength, both on the NHE movement itself (Effect Size = 0.98) and in isokinetic testing (Effect Size = 0.52). This is the primary goal of the NHE—strengthening the muscle while it lengthens, which is crucial for sprinting and preventing injuries.
- Good for Concentric Strength: It also led to significant gains in concentric (shortening) strength (Effect Size = 0.42).
- Not for Isometric Strength: Interestingly, NHE training did not produce significant gains in isometric (static) strength.
So, the takeaway is clear: if you want to build powerful, resilient hamstrings, especially eccentrically, the NHE is one of the best tools for the job.
The Surprising Truth About Volume
Here’s where it gets really interesting. The researchers conducted a meta-regression to see if doing more work—more reps, more sets, more frequent sessions—led to greater strength gains. The answer was a resounding no.
The analysis found no association between strength gains and training volume variables. This means that, within the ranges studied, the groups doing higher volumes didn't necessarily get stronger than the groups doing lower volumes.
This is a huge finding for coaches and athletes. It directly pushes back against the 'more is always better' mentality. For an exercise as demanding as the NHE, performing excessive volume appears to be unnecessary for driving initial strength adaptations, especially in the first couple of months of training.
Your New Nordic Hamstring Prescription
So, if more isn't better, what's the right amount? Instead of chasing a specific dose-response curve, the researchers provided a practical, evidence-based recommendation based on the typical volumes used in the studies that did show significant results.
For individuals new to the NHE (both athletes and non-athletes), here is the programming sweet spot:
- Total Weekly Volume: Aim for approximately 29 to 64 total repetitions per week.
- Frequency: Spread this volume across 2 to 3 sessions per week.
- Duration: High volumes are unnecessary during the first 6-8 weeks of a program.
Example Weekly Setups:
- Lower End (30 reps/week): 2 sessions of 3 sets of 5 reps.
- Mid-Range (48 reps/week): 2 sessions of 3 sets of 8 reps.
- Higher End (60 reps/week): 3 sessions of 4 sets of 5 reps.
The most critical piece of advice is to start progressively. The NHE is notoriously difficult. Don't jump straight to 60 reps a week. Start with a lower volume you can handle with good form and build up over time.
Important Caveats and Context
As with any research, context is key. The authors urge caution when interpreting these results, noting that the overall certainty of the evidence was low to very low. This is common in exercise science reviews but important to remember.
Furthermore, this 'volume ceiling' seems most applicable to those who are inexperienced with the NHE. The paper suggests that individuals who are already proficient and well-trained in the exercise may benefit from increased training volumes to continue making progress. However, more research is needed to confirm this.
For the vast majority of us, the message is to focus on quality and consistency within the recommended range, not on sheer volume.
Key Takeaways for Your Training
To sum it all up, here's what this 2025 meta-analysis means for your hamstring training:
- NHEs Work: They are a top-tier choice for building eccentric hamstring strength.
- Forget 'More is More': For beginners and intermediates, there's no clear benefit to performing excessively high volumes of NHEs.
- Aim for the Sweet Spot: A total of 29-64 reps per week, spread over 2-3 sessions, is a highly effective target.
- Progress Smart: Start at the low end of the volume range and gradually increase as you get stronger. Quality over quantity is the name of the game.
By training smarter, not just harder, you can build stronger, more resilient hamstrings without the wasted effort and unnecessary risk.
Reference
Franke, R. A., Rodrigues, R., Lopez, P., Nakamura, F. Y., & Baroni, B. M. (2025). Dose-Response Relationship for Strength Gains From Nordic Hamstring Exercise: A Systematic Review, Meta-Analysis, and Meta-Regression. Journal of strength and conditioning research, 39(10), 1088–1104. https://pubmed.ncbi.nlm.nih.gov/40991853/