When I sat down with Dr. Martin Refalo from JPS Health & Fitness, we dug into one of the most debated topics in training: how close to failure you really need to go to grow.
Martin recently published a study that explored what actually happens to fatigue and performance when lifters train at different levels of effort, from keeping a few reps in reserve to going all the way to muscular failure.
And the results might change how you think about “hard training.”
The Context: Training Hard vs. Training Smart
Most lifters assume that if they’re not going to failure, they’re leaving gains on the table.
But that assumption doesn’t always hold up.
Martin’s research team wanted to test this belief directly , not just comparing “failure vs. no failure”, but looking at what happens across the full range of effort:
- 3 reps in reserve (3 RIR)
- 1 rep in reserve (1 RIR)
- True muscular failure (0 RIR)
By measuring neuromuscular fatigue through bar speed (velocity loss), they were able to quantify exactly how each level of effort affected recovery and performance, both within the workout and in the days after.
The Study at a Glance
- 24 trained lifters: 12 men and 12 women
- Exercise: Barbell bench press
- Structure: Six sets per session, 4 minutes rest between sets
- Conditions tested: 3 RIR, 1 RIR, and failure
- What they measured: Lifting velocity immediately after training, and again 24 and 48 hours later
Unlike many studies that only test beginners or use arbitrary “non-failure” cutoffs, this one included experienced lifters who were already familiar with RIR-based training , making the results much more applicable to real-world training.
What They Found
1. Fatigue Rises Sharply at Failure
Here’s the clear pattern they found:
- 3 RIR: ~8% drop in bar speed
- 1 RIR: ~13% drop
- Failure: ~25% drop
So while the stimulus from failure may only increase slightly, the fatigue increases dramatically, especially in men.
That means training to failure can limit performance in the same session and make subsequent sets less effective.
“Fatigue increases as you get closer to failure, but once you hit true failure, it rises disproportionately.”
— Dr. Martin Refalo
2. Men and Women Respond Differently
Men experienced a disproportionate jump in fatigue when training to failure.
Women, on the other hand, showed a more linear increase, meaning their fatigue climbed steadily but not exponentially.
This suggests that women may tolerate more near-failure training without the same cost to recovery.
In contrast, men may benefit from stopping 1–2 reps shy to balance stimulus and fatigue.
3. Within-Session Fatigue Matters More Than Next-Day Recovery
Interestingly, most lifters had recovered by 48 hours post-training, regardless of how hard they pushed.
That means the biggest downside of failure training isn’t how sore or tired you feel the next day, it’s how much it reduces your performance within the same workout.
Once fatigue compounds across sets, your ability to maintain output, and thus the total stimulus for muscle growth , goes down.
What This Means for Your Training
1. You don’t need to train to failure to grow.
Stopping 1–2 reps shy of failure provides nearly the same hypertrophic benefit with far less fatigue.
2. Adjust volume and rest based on effort.
If you’re training closer to failure, drop total sets or extend rest periods. If you’re staying further from failure, you can handle slightly higher volume.
3. Be strategic with exercise selection.
Save true failure for lower-risk lifts (machine rows, leg extensions, lateral raises), not heavy barbell movements.
4. Recognize individual differences.
Women often recover faster and handle more frequent hard sets. Men may need a bit more restraint or recovery time between sessions.
5. Monitor both performance and perception.
Martin’s study showed that how “recovered” people felt didn’t always match what their performance data showed.
You need both subjective feedback and objective measures (like reps, load, or bar speed) to make smart programming decisions.
The Bigger Picture
Building muscle and improving body composition isn’t about chasing exhaustion , it’s about managing the balance between stimulus and fatigue.
As Martin’s study reinforces, the goal isn’t to train harder at all costs , it’s to train smart, push where it counts, and recover well enough to keep doing it consistently.
Learn More About The Performance Recomp Method
If you want to train with a system that combines evidence-based programming, optimized recovery, and real-world sustainability, that’s exactly what I coach inside The Performance Recomp Method.
It’s designed for busy professionals over 30 who want visible results without burning out or living in the gym.
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