Podiatrist Addresses the 10 Myths of Barefoot Running

In the following essay, which appears in the current issue of Podiatry Today, Dr. Nick Campitelli, a health and medical advisor to the Natural Running Center, who is board-certified by the American Board of Podiatric Surgery, addresses a hotly debated topic in professional foot-treatment circles.

Tackling The 10 Myths Of Barefoot Running

by Nicholas A. Campitelli, DPM, FACFAS

Barefoot running, minimalist running and natural running are all terms that describe running in a manner that allows our foot to function the way it was designed (or has evolved). This happens through the use of little or no shoe at all. Many runners suffering from chronic injuries are adopting this way of running and are experiencing relief of symptoms to find themselves running with enjoyment and a more relaxing form.

I too have been cured of a running injury, which I suffered from for over eight years after transitioning my gait to that of a “barefoot” runner. Without further ado, here are the 10 myths of barefoot running.

1. Barefoot running leads to stress fractures. Without a doubt, the most common concern with barefoot or minimalist running is the development of a stress fracture. While there have been documented cases of this in the literature, stress fractures occur as a result of a change in activity without gradual adaptation and are not directly related to the shoegear or lack thereof.1 We actually should see a decrease in the likelihood of stress fracture given the change in stride and cadence that one acquires while running barefoot.2

Stress fractures occur secondary to overuse without the body having adapted adequately as proven by Wolff’s Law.3 In fact, if we adhere to Wolff’s law in theory, we should see weaker bone trabecular patterns on those wearing cushioned running shoes due to decreased intrinsic muscle strength, resulting in a proportional decrease in the force acting on the respective bone.4

2.I have flat feet and I need support. Lees and Klemerman have demonstrated that there is no correlation between foot type and running injuries, specifically with a pes planus deformity.5 During barefoot running, we avoid heel striking and land more on our forefoot or midfoot. Once the forefoot strikes the ground, pronation of the entire foot begins (not isolated pronation of the subtalar joint) and continues until the point where the heel touches the ground. Arch height becomes irrelevant as does the commonly described concept of pronation with the heel striking the ground first. With a forefoot/midfoot strike, pronation is very beneficial and helps to absorb shock.

3. I weigh too much. While this is a common excuse to not run, being overweight is not reason enough not to run barefoot or in a minimalist shoe. In 2010, Leiberman and co-workers were able to demonstrate that habitually unshod runners were able to generate smaller collision forces than shod heel strikers.6 In other words, by forefoot striking, we decrease the force that transmits through the lower extremity, thereby reducing torque forces to the ankle, knee and hip joints.7 Clearly, we can see that if people weigh 250 lbs, they would be placing more force through their joints by heel striking then by landing on their forefoot.

4.I have bad knees. Osteoarthritis of the knee is a common concern among many runners, especially older individuals who have run the majority of their lives. There are many theories as to why running is bad or even good for your knees. So many in fact that elliptical machines were invented to be used as a form of exercise similar to running without causing excess pressure to the joints.8 However, these elliptical machines do not reproduce anatomical motions and an in vivo force analysis reveals there is less force with walking than with an elliptical trainer.9-11

As I noted previously, we know that ground reactive forces are greater with heel strike in comparison to unshod or barefoot runners who adapt a more forefoot strike pattern.6 Numerous studies have demonstrated higher ground reactive forces and mechanical stresses to the knee while running in traditional running shoes as opposed to barefoot.12-13 A recent study published in the British Journal of Sports Medicine looked at patients with knee osteoarthritis over 12 months and found no difference between wearing a lateral wedge orthotic versus a control flat insert.14 Similarly, a systematic review of literature demonstrates that external knee adduction moment and pain associated with knee osteoarthritis is higher in individuals wearing sneakers in comparison to those who do barefoot walking.15

5. I can’t do barefoot running because I need to wear my orthotics. Orthotics have become more overutilized in the practice of podiatry then ever before. It is very common for me to see runners present in my office with plantar fasciitis, a normal arch, cushioned running shoes and orthotics they have worn. When running barefoot or in a minimalist shoe, we do not need to control motion at the rearfoot because heel striking is not occurring and “excessive pronation,” as described by Root, does not occur. While we have numerous studies that do not support the use of orthotics for running injuries alone, it becomes a challenge to convince the patient they are not needed.16-20

6. I have plantar fasciitis so barefoot running would be too painful. This article was not intended to discuss the pathomechanics or treatment options of plantar fasciitis. However, we are anecdotally seeing resolution of symptoms in those who adopt this style of running. One potential explanation is the development in strength we see to the intrinsic musculature, specifically the abductor hallucis muscle, which is a primary supporter of the arch.21-25   Another overlooked phenomenon is the fact that the majority of running shoes place your ankle into plantarflexion. This forces the body to compensate by increasing lumbar lordosis and increasing pressure to the heel as opposed to having more even distribution throughout the foot.

7. An atrophied fat pad would prohibit barefoot running. This is another common myth that patients acquire from various sources, including medical professionals. Most, if not all, of us have treated a patient who complains of forefoot pain or calluses, and then simply blames the problem on a lack of adipose tissue or cushioning below the metatarsal heads. While this seems to be a possible etiology, there is no evidence to date that the fat pad of the sole of our foot actually atrophies on the forefoot or the heel region.26,27 With common forefoot pathology such as hammertoe deformities, we do see the fat pad migrate distally producing more prominent metatarsal heads but typically, this is in severe cases, such as rheumatoid arthritis.28 Patients at this stage of a deformity are typically not runners.

8. Barefoot running causes severe calluses. Calluses on our feet form as a result of shear force on the plantar surfaces of the skin that produces excess friction. Shear force that occurs in the horizontal plane is the key to understanding this concept. Direct pressure does not produce calluses or we would see a high preponderance of heel calluses in runners as the majority of runners heel strike.

Root discussed the formation of forefoot calluses secondary to shearing forces associated with propulsion as well as to the central metatarsals due to increased loading for an excessive period of time and abnormal shear.29 Root’s observations hold true for someone who heel strikes when running as we see increased force placed upon the forefoot during what he described as the propulsion phase. Observation of the gait of a barefoot runner or one who strikes with the forefoot/midfoot demonstrates that the propulsion phase as described by Root becomes very minimal in existence, if it even occurs at all.

Good Form Running in association with New Balance provides training to adopt this style of running and we can see that by developing forward momentum, we carry the contralateral limb forward instead of having forefoot propulsion.30 By doing this, we decrease the force present to the forefoot, especially the shear force. Not only is this beneficial for reduction of the shear force but we see a decrease in the ground reactive forces acting on the first metatarsophalangeal joint, which can reduce sesamoiditis.

9. I run long distance and cannot do that barefoot. What many of us fail to realize is that we have been running for thousands of years and we know that early runners began running either barefoot or with very minimal shoegear such as moccasins.31 In 1960, Abebe Bikila won the Olympic Marathon in a record time of 2:15:16.2 while running barefoot.32 Zola Budd recorded numerous middle distance world records while running barefoot in the 1980s. Ken Saxton (well known among the subculture of barefoot runners) finished 14 marathons in 2006 unshod and has since completed a total of 56 marathons, including the Boston Marathon, all while running barefoot.33

10. You could step on glass. This is my favorite excuse for not running barefoot. Numerous times, people ask me the question of “what happens if you step on glass?” There is debate on this topic among medical professionals as well as early adopters to this style of running. What is my answer? “Don’t step on glass.” This concept of “barefoot running” is not about what you are wearing on your foot. It is about how you are running and allowing the foot to perform the way it was designed and intended to perform. Once the form is perfected and the runner abandons heel strike (which runners can typically learn on a treadmill barefoot), the next step is to protect the skin of our foot while not compromising the proprioceptive feedback from ground.

There are numerous options available that have recently become known as minimalist shoegear. FiveFingers (Vibram), Minimus (New Balance) and the Trail Glove (Merrell) are just a few of these shoes.FiveFingers has quickly become the market share leader due to its ability to allow the toes to function individually and allow full range of motion of the forefoot as well as the midfoot and rearfoot joints with a zero drop.34 Nike as well was one of the very first to introduce a less supportive shoe in 2004 known as the Nike Free.35 While this is a very flexible and non-supportive shoe, it does have a considerable amount of cushioning, which can interfere with feedback and increase muscle recruitment to provide control.

In Summary
Barefoot running is about learning to run the way our body was intended to using the foot as an ideal shock absorber and not relying on a shoe that compromises the anatomical position of the foot and places one at risk for injury. Using a true minimalist running shoe can achieve this and still protect the foot from the environmental dangers.

 

References
1. Giuliani J, Masini B, Alitz C, Owens BD. Barefoot-simulating footwear associated with metatarsal stress injury in 2 runners. Orthopedics. 2011 Jul 7;34(7):e320-3. doi: 10.3928/01477447-20110526-25.
2. Edwards WB, Taylor D, Rudolphi TJ, Gillette JC, Derrick TR. Effects of stride length and running mileage on a probabilistic stress fracture model. Med Sci Sports Exerc. 2009 Dec;41(12):2177-84.
3. Stedman’s Medical Dictionary, 28th edition. Lippincott, Williams and Wilkins, Philadelphia, 2005.
4. Wolff J. “The Law of Bone Remodeling”. Berlin Heidelberg New York: Springer, 1986 (Translation of the German 1892 edition).
5. Lees A, Lake M, Klenerman L. Shock absorption during forefoot running and its relationship to medial longitudinal arch height. Foot Ankle Int. 2005;26(12):1081-8.
6. Lieberman DE, Venkadesan M, Werbel WA, Daoud AI, D’Andrea S, Davis IS, Mang’eni RO, Pitsiladis Y. Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature. 2010;463(7280):531-5.
7. Kerrigan DC, Franz JR, Keenan GS, Dicharry J, Della Croce U, Wilder RP. The effect of running shoes on lower extremity joint torques. PMR. 2009 Dec;1(12):1058-63.
8. http://en.wikipedia.org/wiki/Elliptical_trainer [6]
9. Burnfield JM, Shu Y, Buster T, Taylor A.Similarity of joint kinematics and muscle demands between elliptical training and walking: implications for practice. Phys Ther. 2010;90(2):289-305.
10. Lu TW, Chien HL, Chen HL. Joint loading in the lower extremities during elliptical exercise. Med Sci Sports Exerc. 2007;39(9):1651-8.
11. D’Lima DD, Steklov N, Patil S, Colwell CW Jr. The Mark Coventry Award: in vivo knee forces during recreation and exercise after knee arthroplasty. Clin Orthop Relat Res. 2008;466(11):2605-11.
12. Franz JR, Dicharry J, Riley PO, Jackson K, Wilder RP, Kerrigan DC. The influence of arch supports on knee torques relevant to knee osteoarthritis. Med Sci Sports Exerc. 2008 May;40(5):913-7.
13. Burkett LN, Kohrt WM, Buchbinder R. Effects of shoes and foot orthotics on VO2 and selected frontal plane knee kinematics. Med Sci Sports Exerc. 1985;17(1):158-63.
14. Bennell KL, Bowles KA, Payne C, Cicuttini F, Williamson E, Forbes A, Hanna F, Davies-Tuck M, Harris A, Hinman RS. Lateral wedge insoles for medial knee osteoarthritis: 12 month randomised controlled trial. BMJ. 2011 May 18;342:d2912. doi: 10.1136/bmj.d2912.
15. Radzimski AO, Mündermann A, Sole G. Effect of footwear on the external knee adduction moment – A systematic review. Knee. 2011 Jul 4. [Epub ahead of print]
16. Stackhouse CL, Davis IM, Hamill J. Orthotic intervention in forefoot and rearfoot strike running patterns. Clin Biomech (Bristol, Avon). 2004;19(1):64-70.
17. Fields KB, Sykes JC, Walker KM, Jackson JC. Prevention of running injuries. Curr Sports Med Rep. 2010;9(3):176-82.
18. Gross ML, Napoli RC. Treatment of lower extremity injuries with orthotic shoe inserts. An overview. Sports Med. 1993;15(1):66-70.
19. Kilmartin TE, Wallace WA. The scientific basis for the use of biomechanical foot orthoses in the treatment of lower limb sports injuries–a review of the literature. Br J Sports Med. 1994;28(3):180-4.
20. Razeghi M, Batt ME. Biomechanical analysis of the effect of orthotic shoe inserts: a review of the literature. Sports Med. 2000;29(6):425-38.
21. Jung DY, Kim MH, Koh EK, Kwon OY, Cynn HS, Lee WH. A comparison in the muscle activity of the abductor hallucis and the medial longitudinal arch angle during toe curl and short foot exercises. Phys Ther Sport. 2011;12(1):30-5.
22. Headlee DL, Leonard JL, Hart JM, Ingersoll CD, Hertel J. Fatigue of the plantar intrinsic foot muscles increases navicular drop. J Electromyogr Kinesiol. 2008 Jun;18(3):420-5.
23. Wong YS. Influence of the abductor hallucis muscle on the medial arch of the foot: a kinematic and anatomical cadaver study. Foot Ankle Int. 2007;28(5):617-20.
24. Fiolkowski P, Brunt D, Bishop M, Woo R, Horodyski M. Intrinsic pedal musculature support of the medial longitudinal arch: an electromyography study. J Foot Ankle Surg. 2003;42(6):327-33.
25. Emmerich J, Wülker N, Hurschler C. Influence of the posterior tibial tendon on the medial arch of the foot: an in vitro kinetic and kinematic study. Biomed Tech (Berl). 2003;48(4):97-105.
26. Waldecker U. Plantar fat pad atrophy: a cause of metatarsalgia? J Foot Ankle Surg. 2001;40(1):21-7.
27. Waldecker U, Lehr HA. Is there histomorphological evidence of plantar metatarsal fat pad atrophy in patients with diabetes? J Foot Ankle Surg. 2009;48(6):648-52.
28. Mickle KJ, Munro BJ, Lord SR, Menz HB, Steele JR. Soft tissue thickness under the metatarsal heads is reduced in older people with toe deformities. J Orthop Res. 2011 Jul;29(7):1042-6.
29. Root ML, Orien WP, Weed JH. Normal and Abnormal Function of the Foot -Volume 2. Clinical Biomechanics Corp., Los Angeles, CA, 1977
30. http://www.goodformrunning.com/ [7]
31. http://en.wikipedia.org/wiki/Shoe [8]
32. http://en.m.wikipedia.org/wiki/Abebe_Bikila [9]
33. http://www.marathonandbeyond.com/choices/clift.htm [10]
34. “Trend Insight: Minimalist Footwear Category Offers Plenty of Opportunity.” Footwear Insight, September/October 2011: 22.
35. http://en.wikipedia.org/wiki/Nike_Free [11]