Marketing claims are everywhere in the footwear industry. What does actual peer-reviewed science say about zero drop shoes? Below you'll find plain-language summaries of key studies, what they found, and what it means for you.
Key Studies
1. Zero Drop Biomechanics Study (2025)
Study: "Immediate and long-term effects of zero-drop running shoes on lower extremity biomechanics" Published in: Frontiers in Bioengineering and Biotechnology Researchers: Chinese university biomechanics lab
What they did: Seven male runners ran at 13 km/h in both zero drop and 15mm drop shoes. Researchers measured joint angles, forces, and muscle activity immediately and after 8 weeks of adaptation.
What they found: - Zero drop shoes immediately reduced the angle of the foot at landing - Runners naturally shifted toward forefoot striking without being told to - After 8 weeks, stance time (how long the foot touches ground) decreased - The distribution of work shifted from knees toward ankles
What it means for you: Your body will naturally adjust its running form in zero drop shoes, but the changes continue over weeks of use - not just immediately.
2. The Luxembourg Injury Trial (2016)
Study: Randomized controlled trial on heel-to-toe drop and injury rates Published in: American Journal of Sports Medicine Researchers: Luxembourg Institute of Health
What they did: 553 recreational runners were randomly assigned to wear shoes with 0mm, 6mm, or 10mm drop for six months. All shoes had 21mm of cushioning - only the drop differed. Researchers tracked all injuries.
What they found: - No significant difference in overall injury rates between groups - 10mm drop shoes had more knee injuries - 0mm drop shoes had more ankle and foot injuries - Regular runners (more weekly mileage) showed different patterns than occasional runners
What it means for you: Zero drop doesn't prevent all injuries - it changes which body parts are at higher risk. Choose based on your personal injury history, not claims of universal protection.
3. Patellofemoral Joint Stress Study (2022)
Study: "The effect of heel-to-toe drop of running shoes on patellofemoral joint stress during running" Published in: Gait & Posture Researchers: Sports biomechanics lab
What they did: Measured stress on the kneecap joint (patellofemoral) in runners wearing shoes with 0mm, 5mm, 10mm, and 15mm drop.
What they found: - Shoes with drop greater than 5mm significantly increased peak kneecap stress - 10mm and 15mm drop showed the highest stress levels - The increased stress came from greater knee extension moment (the force straightening your knee)
What it means for you: If you have kneecap pain (patellofemoral syndrome), lower drop shoes may reduce stress on that joint. The researchers specifically stated high-drop shoes are "not recommended for patellofemoral pain prevention."
4. Minimalist Shoe Injury Risk Study (2014)
Study: "Examining injury risk and pain perception in runners using minimalist footwear" Published in: British Journal of Sports Medicine Researchers: Prospective cohort study
What they did: Followed runners transitioning to minimalist shoes and tracked pain and injuries over time.
What they found: - Runners in minimalist shoes had increased likelihood of shin and calf pain - Higher forefoot pressure contributed to metatarsal stress fractures - Body weight affected risk - heavier runners had more problems - Runners logging more than 35km per week had elevated injury risk
What it means for you: Transition carefully, especially if you're heavier or run high mileage. The calves and shins take more load in minimal shoes.
5. Systematic Review: Risks and Benefits (2014)
Study: "The Risks and Benefits of Running Barefoot or in Minimalist Shoes: A Systematic Review" Published in: Sports Health (PMC) Researchers: Review of multiple studies
What they did: Analyzed all available research on barefoot and minimalist running to identify consistent patterns.
What they found: - Short-term transition (up to 12 weeks) often causes foot and lower leg pain - Long-term use (20+ weeks) showed plantar-flexor strength gains - All studies agreed: gradual transition is essential - No study could definitively prove minimal shoes prevent or cause injuries overall
What it means for you: Expect discomfort early, but potential strength gains later. Give yourself at least 8-12 weeks to adapt, ideally longer.
6. Footwear Constructions Review (2020)
Study: "Systematic Review of the Role of Footwear Constructions in Running Biomechanics" Published in: Sports Medicine (PMC) Researchers: Meta-analysis of footwear research
What they did: Compared how different shoe features (cushioning, drop, flexibility) affect forces throughout the body.
What they found: - Traditional cushioned shoes increased stress on: quadriceps (vasti muscles), outer knee (lateral tibiofemoral), kneecap joint - Minimalist shoes increased stress on: glutes, inner knee (medial tibiofemoral) during early stance, Achilles tendon during midstance - Neither eliminated stress - both redistributed it differently
What it means for you: There's no "zero stress" option. The question is which structures you want to load more. Traditional shoes load knees more; minimal shoes load calves and Achilles more.
7. Heel Drop and Gait Analysis (2021)
Study: "Biomechanical Analysis of Running in Shoes with Different Heel-to-Toe Drops" Published in: Applied Sciences Researchers: Biomechanics research team
What they did: Detailed motion capture and force analysis of runners in shoes ranging from -8mm to +8mm drop.
What they found: - Higher drop increased foot inclination angle at initial contact (more heel striking) - Higher drop decreased vertical loading rate initially - Higher drop increased peak knee flexion angle and extension moment - Lower/negative drop increased strike index by 19% and vertical loading rate by 32%
What it means for you: Heel-to-toe drop is "a key factor influencing running pattern and lower extremity joint loading." It's not a minor detail - it fundamentally changes how forces travel through your body.
8. Youth Athletes Study (2024)
Study: Oregon State University FORCE Lab research on youth runners Published in: University research release Researchers: OSU-Cascades biomechanics lab
What they did: Studied impact loading rates in youth athletes aged 8-14 running barefoot, in minimal shoes, and in traditional shoes.
What they found: - Barefoot and minimal shoe running doubled impact loading rates compared to traditional shoes - Growing bodies responded differently than adult bodies - Abrupt transitions posed particular risks for younger runners
What it means for you: Be especially cautious with children. Their bodies are still developing, and the research suggests they may be more vulnerable to the impact increases from minimal footwear.
The Big Picture
What Science Consistently Shows
Supported by multiple studies: - Zero drop changes gait patterns and redistributes forces - Lower drop reduces knee stress, increases ankle/calf stress - Higher drop does the opposite - Gradual transition (8-12+ weeks minimum) reduces injury risk - Individual response varies significantly - Comfort-based selection works reasonably well
Not supported by research: - Zero drop prevents all injuries - Everyone should wear zero drop - Traditional shoes are inherently harmful - You can switch immediately without consequences
Choosing Based on Your Body
| If you have... | Consider... |
|---|---|
| Knee pain / patellofemoral issues | Lower drop (0-4mm) |
| Achilles tendinopathy | Higher drop during recovery |
| Calf strains | Higher drop initially, transition slowly |
| Plantar fasciitis | Gradual transition, watch for increased load |
| No specific issues | Self-select based on comfort |
The Transition Protocol
Based on research recommendations:
- Weeks 1-2: Wear new shoes for walking only, 30 min/day
- Weeks 3-4: Short runs (10-15 min) alternating with old shoes
- Weeks 5-8: Gradually increase zero drop run time by 10% weekly
- Weeks 9-12: Continue gradual increase, monitor for pain
- Week 12+: Full transition if no issues
Stop and reassess if you experience persistent pain in calves, Achilles, or metatarsals.
Bottom Line
Zero drop shoes aren't magic, and traditional shoes aren't villains. The science shows real biomechanical differences that matter for specific people and conditions. The best choice depends on your body, your history, and your patience for proper transition.
What zero drop offers is a return to anatomically neutral - something your body can adapt to and potentially benefit from, given enough time.
Studies cited are available on PubMed, PMC, and publisher websites. Search by title for full text access.