Running is the most practical and accessible form of exercise in the United States. An estimated 47 million American’s participate in weekly running as their primary form of exercise. One of the main reasons for this is whether you are training for a 5K, using it as cross-training, or trying to stay in shape, all you need is a T-shirt, shorts and a pair of running shoes to get on the road or trail. However, a recent study found that 31% of novice runners get injured before they ever reach their goal. There are a number of factors that go into this shocking statistic that range from equipment to training intensity or weaknesses throughout the body. As a physical therapist, one of the most commonly asked and confusing questions is “How can I choose the best running shoe for myself?”

 

 

 

 

 

Now, this seems like a simple enough question that should have a straightforward answer, but one quick google search can prove that incorrect. There are sources claiming minimalist footwear is the only shoe for everyone, or that you need to replace your shoes every 100 miles, or that “This is the lightest, best shoe” for every runner. The fact of the matter is, it is not as simple as any that. A lot of this misinformation is from shoe companies or radical viewpoints on one side of the spectrum or the other. Whether you are a clinician looking for a resource, a novice runner trying to make the first big running purchase, or an experienced runner trying to narrow in on your ideal footwear, my goal is to to give an outline of the research on current trends, review how to find the best shoe for your foot to prevent injury, and give runner’s a simple guide to help with selecting the perfect shoe.

 

 

Current Research on Prescription of Running Shoes

 

Theory #1: Prescribing Shoes Based on Arch Height

 

If you have low arches, you may have walked into almost any shoe store and they have examined your feet and told you something to the effect of “we need to put you in a motion-controlled show to prevent any foot injuries” or if you are on the other end of the spectrum, high arches, that this means that you have rigid joints and need a neutral or cushioned shoe to help with the shock absorption.

 

Now, what does the research have to say about this? A study by Knapik et al. in 2014 investigates 3 randomized controlled trials that evaluated the effectiveness of running shoe prescription based on the arch shape on running and training injuries in the military population. When compared, they found that prescribing shoes based on arch height is similar to or worse than prescribed shoes at random for injury prevalence.

 

What does this mean for me as a runner? Arch height has little correlation to injury and should not be a major deciding factor in shoe selection.

 

Theory #2: Prescribing Shoe Based on Pronation While Running

 

Pronation is defined as the rotation of the medial arch inward, resulting in a decrease in arch height. This is commonly measuring between the midline of calf and midline of the calcaneus bisecting the heel during different phases of running. There are a couple of fundamental flaws with prescribing shoes in this way.

 

Problem #1- Pronation is a natural movement of the foot especially with increased weight bearing that acts as a means for shock absorption and forces transference while running. Research on this is inconclusive as some research suggests that overpronation is actually injury protective while other contradict that. (Neat et al. 2014)

 

Problem #2- There is no standard way of measuring pronation or what is defined as overpronation. The current research on this topic focuses on a variety of ways of measuring this: pronation velocity, degree of pronation, midfoot pronation, and time in pronation have all been used. All of these are difficult to measure in a clinic or shoe store without specialized kinematic analysis. This leaves pure observation analysis as the only way to determine “pronation degree”, most running stores or rehab professionals use the midline of the shoe as a reference point. A number of studies have investigated and found a discrepancy between shoe and foot movement. Bishop and colleagues found that there can be as much as 20% difference between shoe movement or position and calcaneal position (Bishop et al. 2012).

 

What does this mean for me as a runner? Prescribing shoes based on overpronation is difficult to analyze and unreliable at decreasing prevalence of running-related injuries.

 

Theory #3: Following Latest Trends (Maximalist versus Minimalist)

 

The push towards minimalist footwear has been around since the mid 90’s when you started seeing an increase in runners going towards a forefoot strike while running. It later gained popularity by Christopher McDougall’s NYT Best-Seller, Born to Run. This ideology later came into further debate with the introduction of maximally cushioned footwear as recently as 2010.

 

Minimalist footwear has been described as any footwear that has decreased insole cushioning or having a decrease in heel-drop angle. On the other end of the spectrum, maximalist cushioned shoes are any shoe that has an increased in cushioning on the insole and was developed to decrease the joint stress that running causes. Studies have claimed a number of advantages for one versus the other. Our goal is to examine what the research says in regards to running economy, loading forces, and running-related injury rates.

 

Running Economy

 

A recent landmark meta-analysis took a look at all available research on the effects of a variety of footwear on running economy. A total of 168 runners were included from the variety of studies and found that there was, in fact, a decrease in oxygen utilization in long-distance running performance. However, the author did note that nearly 25% of the runners involved in the study had the previous barefoot running experience, which could be a contributing factor. More research is needed to come to a definite consensus, but current research suggests that it may be more effective to run in minimalist footwear over long distances (Cheung and Ngai 2016).

 

Loading Forces

 

When comparing various running footwear, it is important to examine how manipulating the type and placement of cushioning effects loading forces due to their link to Running-Related-Injuries. The type of shoe being worn also contributes to slightly altered running biomechanics. For example, it has been demonstrated in the research that wearing minimalist footwear changes the foot strike pattern to a more forefoot dominate position. While a more cushion sole may encourage a heel strike, as there is more support to prevent impact injuries at the heel. These biomechanical differences are important to be aware of when analyzing loading forces throughout the foot and lower body. So what does this mean for loading forces throughout the foot?

 

Napier et. al (2018) found that there was a significant increase in the forefoot, midfoot, and total foot plantar loading with minimalist shoes when compared to maximally cushioned in a controlled environment with 15 recreational runners in a single bout of use. These findings have been further complicated by Kulmala and colleagues, who reported that runners exhibited increased impact forces and loading rate when running in a maximal versus the neutral shoe. This suggests that there may be a difference in the impact of loading forces on the rest of the body and plantar loading forces depending on footwear being worn.

 

One potential explanation is that maximalist footwear masks loading forces and can actually amplify the ground reaction force due to the lack of proprioception in the foot to mediate those forces. Kulmala and colleagues suggest that this may be in part due to increased lower extremity stiffness when landing, which serves to increase the overall impact above the level of the shoe. So what do these findings mean for running-related injuries?

 

Running-Related Injury Prevalence

 

The topic of injury rates is at the core of the discussion between minimalist versus maximalist footwear. The primary discussion point is regarding the prevalence of stress-related injuries in both populations. This centralizes around the impact loading forces that we discussed earlier. A recent observational study of those who self-selected minimalist footwear, Altman and Davis (2012) found that there is an increased rate of the forefoot and lower extremity stress fractures in minimalist shoes. This supports a kinematic analysis by Sinclair that reported an increase in instantaneous loading rates, peak tibial progression, and peak tibial internal rotation that theoretically could increase the likelihood of chronic running-related injuries, such as stress fractures. The major limitations in drawing conclusive ideology behind these findings are that these are a snapshot of untrained athletes using minimalist footwear. There may be some adaptations that occur while slowly transitioning to this footwear that is not being captured due to the length of the study.

 

Sinclair later investigated the relationship of utilizing a forefoot strike pattern with minimalist footwear and tensile loading of the connective structures in the lower leg and foot and found a high rate of Achilles tendon forces and Achilles tendon degradation when compared to neutral and maximalist footwear. The current investigation indicated that minimalist footwear may increase runners risk for Achilles tendon injury, likely due to the altered footstrike pattern. (Sinclair 2016)

 

These preliminary studies have examined either minimalist or maximalist shoes with neutral/typical running shoes and no long-term follow-up. Ryan et. al conducted the most thorough evaluation of the relationship between the risk of injury and shoe type to date. This RCT included 99 runners who were randomly assigned a neutral traditional/maximalist (Nike Pegasus 28), partial minimalist (Nike Free 3.0 V2), or full minimalist shoe (Vibram 5-Fingers Bikila). All runners underwent a 12-week training program for a 10km race and the number of injuries and running-related pain were reported. A total of 23 injuries were reported with the highest proportion of injured runners coming from the Nike Free (partial minimalist) compared with the two other conditions (Pegasus and 5-Fingers). Runners in the full minimalist shoe reported greater shin and calf pain than runners in both other footwear groups, while those in maximalist footwear reported an increase in the knee, hip, and low back pain. Their conclusions were as follows:

 “Running in minimalist footwear appears to increase the likelihood of experiencing an injury and running-related pain in runners otherwise new to this footwear category while training for a 10 km event (12 weeks). Using a full minimalist design; however, may reduce pain at the knee, hip and pelvis, and lower back suggesting there is merit in using a full minimalist design for injury prevention with appropriate pre-conditioning of soft-tissue in the shin and calf.” (Given the fact that the experience of pain was significantly more important in the case of the ultra-minimalist group.)

Ryan, Michael, et al. “Examining the Potential Role of Minimalist Footwear for the Prevention of Proximal Lower-Extremity Injuries.” Footwear Science, vol. 5, no. sup1, 2013, doi:10.1080/19424280.2013.799538.

What does this mean for me as a runner? – It depends. The current research is inconclusive on if shoe selection is a major indicator in Running-Related Injuries. All studies show significant variation in findings and variability between participants. What works for one runner, may be harmful to another. Keep in mind etiology of any previous injury for the clients seeking advice.

Conclusions and Considerations for Choosing the Best Running Shoe

With the research being inconclusive regarding the effectiveness of these various footwear options, it is very difficult to accurately predict who will fare better in various footwear. Here is a summary of the findings:

• If the runner has a history of Achilles tendinopathy or lower limb stress fractures, minimalist footwear may not be the best selection.
• If the runner has a history of the low back, hip or knee pain, maximalist cushioned shoes may not be the best selection.
• In order to transition to minimalist shoes, Warne et al. suggest a minimum of a 4-week transition period in which you gradually increase following the 10% of usage rule.

The other component to consider is that of manufacturers defect. Bruce Wilk and colleagues have reported on the correlation to a defect in the running shoe and developing plantar fasciitis in a professional triathlete. Most shoe companies will readily send you a new pair and save you the headaches of any unnecessary injuries. Below is a checklist developed by Chris Johnson, PT from Zeren PT in Seattle WA to accurately screen shoes for these defects and ensure that the best possible fit is made.

Chris Johnson’s Review of Tips & Suggestions for Determining Proper Running Shoe Size & Fit

1. Bring your preferred pair of socks.
2. Remove the inner sole and make sure that it fully captures your foot.
3. Feel around the inside of the shoe for “hot spots” or areas that may be abrasive.
4. Don and fully lace both shoes without pulling the laces too tight.
5. Your toes should have adequate room in the toe box in a vertical and side-to-side manner.
6. The shoe’s shape should feel comfortable and not overly curved nor straight relative to your foot.
7. The shoes should flex well just behind the ball of your foot.
8. The shoes should provide adequate protection for the bottom of your feet from rocks and uneven terrain
9. Fit shoes to your longest toe of your longest foot.
10. Your heels should be snug in the heel counter and there should be little up and down movement.
11. Try on your shoes at the end of the day, preferably after running or walking as feet normally swell by day’s end.
12. Make sure to take them for a test run.
13. If you use orthotics to make sure they fit inside the shoe without compromising the fit and are positioned on a shoe with a stable platform.

If you are currently using a shoe and are curious if this is the best running shoe for you, check out this article by Dr. John Mullen, DPT, CSCS from COR. 8 Signs You’re Wearing the Wrong Running Shoe

Bottom Line

1. Experienced Runners Without Injuries – Keep doing what you are doing. There is no need to break the wheel!
2. Novice Runners- Try a few different pairs and go with what you find comfortable. Don’t be sold by orthotics, pronation or the trendy crowds.
3. Runner’s who are repeatedly injured no matter what shoes, maybe it is more than the shoe. Consider getting screened by one of our highly trained Sports Physical Therapists for the following issues:
   • Running biomechanics
   • Training schedule
   • Movement patterns
   • Other Underlying Conditions

• Training Tips
  • Wear a variety of shoes while training. Malisoux et al. suggest that this may help to distribute the stresses that cause repetitive running-related injuries to different tendons.

Call to Learn More!

 

References:

1. Knapik, J., Trone, D., Tchandja, J., & Jones, B. (2014). Injury Reduction Effectiveness of Prescribing Running Shoes on the Basis of Foot Arch Height: Summary of Military Investigations Journal of Orthopaedic & Sports Physical Therapy, 1-25 DOI: 10.2519/jospt.2014.5342
2. Neal, Bradley S, et al. “Foot Posture as a Risk Factor for Lower Limb Overuse Injury: a Systematic Review and Meta-Analysis.” Journal of Foot and Ankle Research, vol. 7, no. 1, 2014, doi:10.1186/s13047-014-0055-4.
3. Bishop, Chris, et al. “Recommendations for the Reporting of Foot and Ankle Models.” Journal of Biomechanics, vol. 45, no. 13, 2012, pp. 2185–2194., doi:10.1016/j.jbiomech.2012.06.019.
4. Cheung, R.t., and S.p. Ngai. “Effects of Footwear on Running Economy in Distance Runners: A Meta-Analytical Review.” Journal of Science and Medicine in Sport, vol. 19, no. 3, 2016, pp. 260–266., doi:10.1016/j.jsams.2015.03.002.
5. Napier, C., et al. “Kinetic Risk Factors of Running-Related Injuries in Female Recreational Runners.” Scandinavian Journal of Medicine & Science in Sports, vol. 28, no. 10, 2018, pp. 2164–2172., doi:10.1111/sms.13228.
6. Ogston, Jena Kay. “Comparison of in-Shoe Plantar Loading Forces between Minimalist and Maximalist Cushion Running Shoes.” Footwear Science, vol. 11, no. 1, 2019, pp. 55–61., doi:10.1080/19424280.2018.1561760.
7. Kulmala, Juha-Pekka, et al. “Running in Highly Cushioned Shoes Increases Leg Stiffness and Amplifies Impact Loading.” Scientific Reports, vol. 8, no. 1, 2018, doi:10.1038/s41598-018-35980-6.
8. Altman, Allison R., and Irene S. Davis. “Barefoot Running.” Current Sports Medicine Reports, vol. 11, no. 5, 2012, pp. 244–250., doi:10.1249/jsr.0b013e31826c9bb9.
9. Sinclair, J., et al. “Effects of Minimalist and Maximalist Footwear on Achilles Tendon Load in Recreational Runners.” Comparative Exercise Physiology, vol. 11, no. 4, 2015, pp. 239–244., doi:10.3920/cep150024.
10. Sinclair, Jonathan, et al. “The Influence of Minimalist and Maximalist Footwear on the Kinetics and Kinematics of Running.” Footwear Science, vol. 8, no. 1, 2016, pp. 33–39., doi:10.1080/19424280.2016.1142003.
11. Ryan, Michael, et al. “Examining the Potential Role of Minimalist Footwear for the Prevention of Proximal Lower-Extremity Injuries.” Footwear Science, vol. 5, no. sup1, 2013, doi:10.1080/19424280.2013.799538.
12. Warne, J. P., et al. “A 4-Week Instructed Minimalist Running Transition and Gait-Retraining Changes Plantar Pressure and Force.” Scandinavian Journal of Medicine & Science in Sports, vol. 24, no. 6, 2013, pp. 964–973., doi:10.1111/sms.12121.
13. Wilk, Bruce R., et al. “Defective Running Shoes as a Contributing Factor in Plantar Fasciitis in a Triathlete.” Journal of Orthopaedic & Sports Physical Therapy, vol. 30, no. 1, 2000, pp. 21–31., doi:10.2519/jospt.2000.30.1.21.
14. Malisoux, L., et al. “Can Parallel Use of Different Running Shoes Decrease Running-Related Injury Risk?” Scandinavian Journal of Medicine & Science in Sports, vol. 25, no. 1, 2013, pp. 110–115., doi:10.1111/sms.12154.