When it comes to running shoes, the choices can feel overwhelming: cushioning vs. stability, carbon plates vs. neutral soles, wide toe boxes vs. snug fits. But what if the best advice is surprisingly simple: pick the pair that feels the most comfortable?
That’s the idea behind the Comfort Filter, a concept introduced by biomechanics expert Professor Benno Nigg in 2015. His theory suggests that when you slip on a pair of shoes, your body subconsciously steers you toward the pair that minimises stress on your joints. In other words, comfort isn’t just a “nice-to-have”—it might be your body’s way of protecting itself from injury.
Sounds easy, right? Try on a few pairs, choose the one that feels best, and you’re set. But as with most things in running, it’s not quite that simple.
What the Research Says
Several studies back up the Comfort Filter idea:
- The Preferred Movement Path (Nigg et al., 2015): Runners naturally choose shoes that let their bodies move efficiently, reducing abnormal loading on joints and tissues.
- Energy Efficiency (Mundermann et al., 2001): Runners reported lower oxygen use and better efficiency in shoes they rated as more comfortable.
- Pain & Effort (Miller et al., 2020): Comfortable shoes weren’t just easier on the feet—they also reduced overall perceived exertion and cut down on reports of musculoskeletal pain.
- Military Insights (Knapik et al., 2009): Soldiers allowed to pick their own shoes had fewer injuries than those assigned footwear based on arch type or pronation.
Taken together, the evidence suggests that your body might know best—comfort often points to efficiency, lower strain, and fewer injuries.
The Limits of Comfort
Of course, it’s never quite that straightforward. Comfort is subjective—and sometimes deceptive.
A shoe that feels soft and plush at first may actually increase stress on certain areas (like the Achilles tendon).
New runners often lack the “body awareness” to detect subtle warning signs. What feels fine at mile two may feel disastrous at mile twenty.
Comfort doesn’t account for training load, injury history, or biomechanics—all of which play a huge role in long-term running health.
Currently, there’s no universal “gold standard” for prescribing running shoes. Until large-scale studies confirm that comfort alone can reliably prevent injuries, the Comfort Filter should be viewed as a helpful guide, not the ultimate solution.
So, how should you choose running shoes?
Think of the Comfort Filter as your starting point:
✅ Decide what you want from a shoe: training, racing, trail, fitness, injury protection.
✅ Consider your personal history—past injuries, niggles, and any chronic issues.
✅ Consider your training goals and mileage—what works for a 5k might not hold up.
✅ Now disregard any shoe that fails your individual Comfort Test.
✅ Finally, create an analysis with RUNRIGHT-3D; its objective, data-rich content, helps the running store differentiate which shoe “scores” best for your needs.
The Bottom Line
The Comfort Filter is a powerful and practical tool. It reminds us that our bodies are remarkably good at self-optimising—comfort often reflects reduced stress and more efficient movement. But it’s not foolproof.
Listen to your body, but don’t ignore top-tier tools like RUNRIGHT-3D, which offers in-depth objective data that traditional approaches can only dream of.