Low drop vs zero drop — what's actually the difference and does it matter which you choose? A clear guide to heel-to-toe drop numbers and how they affect your running.
The Drop Number Explained
Here’s the core thing you need to understand: drop is the height difference between your heel and your forefoot in a shoe.
Not the overall cushioning. Not how minimal the shoe is. Just the height difference between heel and toe.
When you stand barefoot on flat ground, your heel and toes are at the same height. That’s 0mm drop. That’s what “zero drop” means. When you step onto a traditional running shoe with a 12mm heel, your heel is elevated 12mm higher than your toes. That’s a 12mm drop.
Here’s where it gets interesting: drop is measured independently from stack height. A shoe can have:
- 10mm drop with 12mm stack height (traditional heel-elevated shoe)
- 4mm drop with 8mm stack height (low-drop minimal)
- 0mm drop with 6mm stack height (barefoot minimal)
- 0mm drop with 24mm stack height (cushioned zero-drop like Altra Escalante)
Drop tells you about heel elevation. Stack height tells you about total cushioning. They’re different measurements.
What Drop Actually Changes
When you run in a shoe with heel elevation, your body posture changes:
With 10mm heel elevation, your ankle is more flexed. Your calf is shortened. Your body leans slightly forward. Your center of gravity shifts. Your foot strike pattern often shifts toward heel striking. Your Achilles tendon operates in a shortened range.
With 0mm drop, your ankle angle is more neutral. Your calf is at fuller length. Your body is more upright. Your center of gravity shifts back. Your foot strike pattern naturally shifts toward midfoot or forefoot. Your Achilles tendon works through a fuller range.
With 4-8mm drop, you get a middle ground. The elevation is less dramatic than traditional shoes but still present. Your body doesn’t need to adjust as much as it would with zero drop, but you’re still getting closer to natural positioning than traditional shoes offer.
The biomechanical differences are real. This isn’t marketing. This is how your body responds to different geometric inputs.
The Drop Spectrum
Understanding where different shoes fall on the drop spectrum helps you pick the right transition path.
Traditional Drop (8-14mm)
Your mainstream running shoe. Nike, Asics, Brooks, Saucony—almost all mass-market shoes live here. This is what 80%+ of runners wear.
At 10-12mm drop, you get maximum heel elevation. Your calf is most shortened. Your foot strike is most influenced toward heel striking. Your body doesn’t need to adapt at all—this is what you’re probably used to.
For transition: This is your baseline. If you’re considering dropping down, you’re moving away from this.
Low Drop (4-8mm)
The transitional zone. This is where specialty brands put their mainstream shoes and where traditional brands put their “minimal” lines.
Examples:
- Brooks PureFlow: 6mm drop
- Saucony Peregrine: 4mm drop (trail)
- Altra Torin: 4mm drop
- Topo Athletic Terraventure: 5mm drop
At 4-8mm drop, your heel elevation is noticeable but reduced. Your calf starts engaging more. Your foot strike begins shifting naturally. You get some benefits of natural running without the full commitment of zero drop.
For transition: This is the “gateway” zone. Most runners who want to explore natural running without going full barefoot find their home here.
Zero Drop (0mm)
Your heel and forefoot are at exactly the same height. No elevation whatsoever. Natural foot positioning. Maximum proprioceptive feedback.
Examples:
- All Altra shoes: 0mm drop
- All Xero Shoes: 0mm drop
- All Vivobarefoot shoes: 0mm drop
- Merrell Vapor Glove: 0mm drop
- New Balance Minimus: 0mm drop
At 0mm drop, your body makes the biggest biomechanical shift. Everything I described about calf engagement and foot strike applies at maximum intensity. Your feet and calves need adaptation time. The benefits are also maximum.
For transition: This is the “all in” choice. You’re committing to the full barefoot running experience.
Negative Drop (rare)
A few niche shoes have negative drop, meaning the heel is lower than the forefoot. This is exceedingly rare and mostly only in highly specialized shoes. Skip this for now.
Low Drop vs Zero Drop: The Practical Difference
So here’s what actually changes when you go from low drop (say, 6mm) to zero drop (0mm):
Calf and Achilles Engagement
In 6mm drop shoes, your calf is slightly shortened from its neutral length, but not dramatically. Your Achilles works through a moderate range.
In zero drop, your calf is at full neutral length. Your Achilles works through the maximum range. During the first few weeks, this increased engagement causes soreness and tightness in your calves. This is completely normal and temporary.
Foot Strike Pattern
In 6mm drop, your natural foot strike is still somewhat influenced toward heel striking, though not as much as traditional shoes.
In zero drop, your foot strike naturally shifts toward midfoot striking or forefoot striking. You don’t have to consciously change your form—your body figures it out naturally. But it takes time.
Biomechanical Stress
In 6mm drop, the transition is manageable. Your body doesn’t need to adapt dramatically. You can increase mileage relatively quickly.
In zero drop, the transition is significant. Your feet, calves, shins, and even your hips are all working differently. Your body needs time to adapt. Rushing the transition here is where injury risk comes from.
Ground Feel
In 6mm drop shoes, you get decent ground feel but the slight heel elevation still insulates you somewhat from terrain changes.
In zero drop, you feel everything. Every pebble, every texture change, every subtle grade variation. This feedback is powerful for proprioceptive development, but it’s also an adjustment.
Which Should You Choose?
The answer depends on where you’re coming from and where you want to go.
Choose Low Drop (4-8mm) If:
- You’re currently running in traditional 10-12mm drop shoes
- You want to explore natural running without going full barefoot
- You’re building up foot strength but not ready for the full transition
- You’re training for a race and don’t want to experiment with new geometry
- You have some foot issues that need gentle introduction to new mechanics
- You want benefits of natural running with less dramatic adaptation
Choose Zero Drop If:
- You’re ready to commit to the full barefoot running experience
- You’re willing to spend 8-12 weeks on a conservative transition
- You’re curious about maximum ground feel and foot development
- You’re not racing soon (give yourself time to adapt)
- You’ve already done some minimalist running or low-drop running
- You want the most natural foot positioning possible
How to Transition Down the Drop Spectrum
The key to successful drop reduction is gradual volume progression.
From Traditional (10-12mm) to Low Drop (6-8mm)
Week 1-2: One run per week in low-drop shoes. Keep it short—10-15 minutes max. All other runs in traditional shoes.
Week 3-4: Two runs per week in low-drop shoes. Extend to 15-20 minutes if calf soreness has settled. Still running traditional shoes for other workouts.
Week 5-8: Three runs per week in low-drop shoes. You can now do longer runs if soreness is gone. Can reduce traditional shoes if desired.
Week 8+: You can do all your running in low-drop if you want, or keep it as your primary shoe.
Calf soreness timeline: Expect 3-5 days of noticeable soreness in weeks 1-2, fading by week 3-4.
From Low Drop (6-8mm) to Zero Drop (0mm)
Week 1-2: One run per week in zero drop. Start even shorter—10 minutes max. All other runs in low-drop shoes.
Week 3-4: Two runs per week in zero drop. Extend slightly to 12-15 minutes. Most runs still in low-drop.
Week 5-8: Gradually build zero-drop runs while maintaining low-drop volume. By week 8, you can do 2-3 zero-drop runs per week.
Week 9-12: Most of your running in zero drop. Keep one lower-intensity run in low-drop per week if desired for recovery.
Calf soreness timeline: Expect 5-7 days of noticeable soreness in week 1, with lower-level soreness lasting 3-4 weeks. This is normal.
Direct Transition: Traditional to Zero Drop
If you’re determined to go straight from traditional shoes to zero drop:
Week 1: 10 minutes, one time per week. That’s it. This sounds too short, but it’s the safe amount for a dramatic biomechanical change.
Week 2-3: 10-15 minutes, twice per week. Still very conservative.
Week 4-6: Gradually build to 15-20 minutes, maintaining 2-3 runs per week in zero drop.
Week 7-12: Build gradually to your normal distance. Expect this to take 12 weeks minimum, not 8.
Calf soreness timeline: Week 1-2 will be significant soreness. Week 3-4 will be moderate. By week 5-6 you should feel better. Full adaptation takes 12 weeks.
Warning signs to slow down:
- Persistent sharp pain (not soreness) in shins
- Swelling in feet or ankles
- Pain that worsens as the run progresses
- Pain that doesn’t improve day-to-day
If you hit any of these, back off. You’re rushing.
Frequently Asked Questions
What is considered low drop in running shoes?
Low drop is typically 4-8mm. It’s less heel elevation than traditional shoes (8-12mm drop) but not zero. A 6mm drop shoe puts your heel 6mm higher than your toes, while a 4mm drop is 4mm higher. Low drop is the “transitional” zone between traditional and zero.
Is zero drop the same as flat?
Zero drop means your heel and forefoot are at the same height (0mm difference). Flat can mean different things—some people use it to mean zero drop, others use it for any shoe under 8mm drop. Zero drop is the technical term; flat is layman’s terminology.
Is zero drop better than low drop?
Not inherently. Zero drop offers more natural foot position, but low drop provides a gentler transition if you’re coming from traditional shoes. Zero drop is better if you want maximum ground feel; low drop is better if you need a compromise between protection and minimalism.
Can I go straight to zero drop?
It depends on your current shoes and fitness. If you’re coming from traditional 10-12mm drop shoes, jumping to zero drop is a significant biomechanical change. Most experts recommend transitioning through low drop (6-8mm) first, or if going straight to zero, being extremely conservative with volume and duration.
What drop do barefoot shoes have?
Barefoot shoes are always zero drop (0mm). The entire category is built on the principle of zero heel-to-toe elevation. Some barefoot shoes have less cushioning (5-8mm stack height) and some have more (15mm+), but all true barefoot shoes are zero drop.
Why Drop Matters More Than You Think
Drop affects biomechanics, ground feel, proprioception, and adaptation timeline. It’s not the only factor in choosing shoes, but it’s a critical one.
Understanding the drop spectrum helps you:
- Make informed choices about whether low-drop or zero-drop fits your running
- Plan a realistic transition timeline
- Avoid injury by matching adaptation to your shoe changes
- Understand why your feet feel different in a new shoe (it’s the drop, not just cushioning)
Further Reading
If you want more context on barefoot running broadly, check out my barefoot vs minimalist vs zero drop explained guide.
For the full spectrum of flat shoes from low to zero drop, see my flat running shoes guide.
For comprehensive zero-drop shoe options, check out my best barefoot running shoes for beginners or best minimalist running shoes roundups.
Conclusion
Low drop vs zero drop isn’t about right or wrong. It’s about where you are in your running journey and what you’re ready for.
Low drop is the bridge. It gets you from traditional shoes toward natural running without the full commitment. It’s lower risk, gentler on your body, and still delivers real benefits.
Zero drop is the full experience. Maximum natural position, maximum proprioception, maximum adaptation time. It’s worth it if you’re ready, but you have to be intentional about the transition.
Either way, you’re moving toward a more natural relationship with the ground. That’s the important part.