Modern advances (and claims) have not done much for injury risk!

Runners assign a huge level of importance to footwear with respect to injury risk. In my opinion, this is more based on effective marketing than it is based on fact and is backed by the sentiments expressed by respected biomechanist Daniel Lieberman, PhD at the 40th sports medicine symposium at the Boston marathon:

“Since the advent of the modern running shoe in 1972…injury rates have not declined in 30 years even as major advances seem to have been made in running shoe technology over that time.”

Prescription of shoes based on arch height and pronation

For years people have been given shoes based on levels of pronation or arch height. This persists even in the presence of research showing that both methods do not help to lower injury risk:

• A review of three studies (Total recruits across studies = 7203) found that assigning shoes based on arch type had no bearing on injury rate in military recruits during basic training¹.
• A study of 927 novice runners found that people who had moderate pronation had no increase in injury risk when using a neutral shoe ².
• A study of 81 female runners found increased pain for “neutral” runners in “neutral” shoes versus “stability” shoes. They also found increased pain in “pronators” in “stability” shoes versus “neutral” shoes. Motion control shoes increased pain at rest, daily living, and with running³.

What we need to understand is that each and every human body is different. A small number of categories of foot type, or shoes, just isn’t enough to help put someone in a pair of shoes that work for them. Pronation is actually a good thing, it is the body’s shop absorption at the foot/ankle. So, how do people decide if someone is doing too much or too little of it? Outside of a university gait lab with expensive and complex sensors there is much subjectivity in measurement. In fact, even with complex measurement we do not really have numeric values for “over” or “under” pronation as it is likely that what is too much for one person would not be for another due to the other parts of the body above it in the kinetic chain (e.g. knee, hip, trunk). Simply, we cannot categorize people this way! A powerful example is world-renowned runner and two-time Olympic 10,000m gold medalist Haile Gebrselassie (His marathon world record set aged 35 of 2:03:59 is the current masters’ record and has only been bettered by younger current athletes four times since!). I wonder what would have happened to his career if he had been put in stability shoes due to his “over-pronation”?! Interestingly, whenever I shows this at talks that I do, people express surprise that he did so well and describe it with words such as “worrying”, “scary”, “nauseating” to watch. Hearing those words makes you wonder how much our mind has been shifted by the anti-pronation marketing!

The trend of the minimalist and maximalist shoe

Shoe companies are still using the categories we allude to above (motion control, stability, neutral). I think they realize that they don’t work and that there are messages like mine pointing this out, but they also do not want to remove them as they have been such a successful marketing tool. Instead, they have added more categories – minimalist and maximalist shoes. Minimalist shoes (e.g. Altra) and maximalist shoes (e.g. Hoka) have become more trendy, but like the other categories many of the claims do not stand up to muster.

The minimalist shoe has been encouraged by the idea that people will run more naturally like someone running barefoot. The idea is suggested that they are better than regular shoes which do not promote our natural biomechanics. Part of this trend also encompasses “zero-drop” shoes. Maximalist shoes have been encouraged by the thought that increased shock absorption will help runners by reducing the load.

– When we look at the evidence on minimalist/zero-drop shoes:

To summarize, with minimalist shoes we generally see higher loading of the lower extremity with an increased risk of injury to the foot/ankle. There appears to be a benefit for those with patellofemoral pain (anterior knee pain), but as we discuss below there may be simpler (and cheaper!) alternatives.

– Looking at the maximalist shoes:

To summarize, there is some research suggesting an increase in loading in maximalist shoes. This increase may not be uniform at various parts of the leg, but no research has shown reduced loading at any particular joint, muscle, or tendon. With this, no research has shown a significant difference in injury rates when compared with regular shoes.

So when looking at maximalist and minimalist shoes, it could be argued that the switch to maximalist shoes may be the safer switch to make, but it hasn’t been shown to yield any significant discernible benefit! Yes, they may feel better over a run, but they have not been shown to actually do anything beneficial. My instinct is that running with these large (and in some cases heavy) shoes adds extra inertia that a runner does not need to deal with. The switch to minimalist shoes is riskier but could be beneficial for the right condition (e.g. patellofemoral pain) if done slowly enough. Even in this case, there could be other options which we will mention in the conclusion!

Barefoot Running

It is worth covering this as often these questions are asked:

“Isn’t barefoot running more natural?”

“Doesn’t it promote the mechanics that we had before the advent of footwear?”

“Isn’t natural better for you?”

While I do agree with natural treatments for certain conditions there just isn’t compelling evidence to encourage more runners to go barefoot! I wrote more about this in these blogs (1 and 2) and haven’t seen any research that has changed my thoughts.

Conclusion and recommendations

• There is no conclusive evidence that there is a valid way of prescribing/fitting a running shoe:
  • Be careful of trends and advertising claims.

• Find a shoe that is comfortable, requires no break-in, and buy another shoe that is similar.
  • This advice comes from a 2015 paper by Nigg that describes using your “comfort Filter”. This helps you find the right shoe that helps you follow a motion path that is natural to your body versus one that is fighting it¹².
    • There is still a place for shoe fitters, but you want to see one who is experienced and who listens to you well. If a shoe doesn’t feel good to you, the odds are that it isn’t!
  • It also comes from research that shows reduced injury risk of 39% by rotating shoes!!!¹³.
  • Using two slightly different shoes is likely beneficial as the loading patterns run to run will be slightly different.

• Changes to footwear should be done with caution when:
  • Attempting to promote performance – a lighter shoe improves running economy which will help endurance athlete race times¹⁴.
  • Responding to injury that is not responding to other measures. In most cases exercise has the best evidence for treating running injuries in not only the short-term but also the long term. As we have looked above there are risks of injury when changing shoes and that is all we need if recovering from one injury. As such, changes should probably be gradual (e.g. weeks to months, not days! Suggestion of 6-months to transition to minimal) and with the supervision of a trained individual who is looking at the global picture (e.g. a PT that will assess your running gait and body as a whole rather than becoming too focused on the foot – e.g. Andrew Walker, PT ?).

• When are looking at your first pair of running shoes or changing shoes it is well worth going to a store where you can run in them and they have a good return or swap policy.
  • A shoe that is comfortable walking in around the store might not be comfortable to run in.
  • If you cannot return after running in them for a couple of runs you may end up continuing to run in them when they are the wrong shoe for you and that may contribute to injury risk.
• To the points above, we have much better options than shoe changes to address injury. Here are some great examples:
  • Increasing running cadence. We have discussed this in a previous blog and is nicely illustrated in the picture below:
  • Reducing training error. Using tools such as the Acute:Chronic Workload Ratio (ACWR) to ensure that mileage changes are not too great and likely to contribute to injury risk (see our blog on ACWR here).

Our wooden runner might have a bit of an overstride and benefit from increasing his cadence! (Image developed from graphic by Dr Rich Willy.)

Hopefully, the above has helped you to see beyond the marketing! New shoes are fun, but don’t let that or trends lead you to get injured! If you have further questions you are always welcome to reach out via email or a call. If you have an injury or you want to improve performance you can always consider a FREE discover visit to see if I can help you! As always feel free to message me, call me, or email if you have questions ?

References:

1. Knapik JJ, Trone DW, Tchandja J, Jones BH. Injury-reduction effectiveness of prescribing running shoes on the basis of foot arch height: summary of military investigations. J Orthop Sports Phys Ther. 2014;44(10):805-12.
2. Nielsen RO, Buist I, Parner ET, et al. Foot pronation is not associated with increased injury risk in novice runners wearing a neutral shoe: a 1-year prospective cohort study. Br J Sports Med. 2014;48(6):440-7.
3. Ryan MB, Valiant GA, Mcdonald K, Taunton JE. The effect of three different levels of footwear stability on pain outcomes in women runners: a randomised control trial. Br J Sports Med. 2011;45(9):715-21.
4. Willy RW, Davis IS. Kinematic and kinetic comparison of running in standard and minimalist shoes. Med Sci Sports Exerc. 2014;46(2):318-23.
5. Malisoux L, Chambon N, Urhausen A, Theisen D. Influence of the Heel-to-Toe Drop of Standard Cushioned Running Shoes on Injury Risk in Leisure-Time Runners: A Randomized Controlled Trial With 6-Month Follow-up. Am J Sports Med. 2016;44(11):2933-2940.
6. Firminger CR, Fung A, Loundagin LL, Edwards WB. Effects of footwear and stride length on metatarsal strains and failure in running. Clin Biomech (Bristol, Avon). 2017;49:8-15.
7. Sinclair J, Richards J, Selfe J, Fau-goodwin J, Shore H. The Influence of Minimalist and Maximalist Footwear on Patellofemoral Kinetics During Running. J Appl Biomech. 2016;32(4):359-64.
8. Sinclair J, Richards J, Shore, H.Effects of minimalist and maximalist footwear on achilles tendon load in recreational runners. Comparative exercise physiology. 2015; 11(4):239.-244
9. Agresta, C, Kessler, S, Southern, E, Goulet, G.C, Zernicke, R. and Zendler, J.D. Immediate and short-term adaptations to maximalist and minimalist running shoes. Footwear Science 2018;20(2):1-13.
10. Pollard CD, Ter har JA, Hannigan JJ, Norcross MF. Influence of Maximal Running Shoes on Biomechanics Before and After a 5K Run. Orthop J Sports Med. 2018;6(6):2325967118775720.
11. Sinclair J, Richards J, Selfe J, Fau-goodwin J, Shore H. The Influence of Minimalist and Maximalist Footwear on Patellofemoral Kinetics During Running. J Appl Biomech. 2016;32(4):359-64.
12. Nigg BM, Baltich J, Hoerzer S, Enders H. Running shoes and running injuries: mythbusting and a proposal for two new paradigms: ‘preferred movement path’ and ‘comfort filter’. Br J Sports Med. 2015;49(20):1290
13. Malisoux L, Ramesh J, Mann R, Seil R, Urhausen A, Theisen D. Can parallel use of different running shoes decrease running-related injury risk?. Scand J Med Sci Sports. 2015;25(1):110-5.
14. Fuller JT, Thewlis D, Tsiros MD, Brown NAT, Buckley JD. Six-week transition to minimalist shoes improves running economy and time-trial performance. J Sci Med Sport. 2017;20(12):1117-1122.

Infographic references:

• Lenhart RL, Thelen DG, Wille CM, Chumanov ES, Heiderscheit BC. Increasing running step rate reduces patellofemoral joint forces. Med Sci Sports Exerc. 2014;46(3):557-64.
• Lenhart R, Thelen D, Heiderscheit B. Hip muscle loads during running at various step rates. J Orthop Sports Phys Ther. 2014;44(10):766-74, A1-4.
• Lyght M, Nockerts M, Kernozek TW, Ragan R. Effects of Foot Strike and Step Frequency on Achilles Tendon Stress During Running. J Appl Biomech. 2016;32(4):365-72.
• Wellenkotter J, Kernozek TW, Meardon S, Suchomel T. The effects of running cadence manipulation on plantar loading in healthy runners. Int J Sports Med. 2014;35(9):779-84.
• Heiderscheit BC, Chumanov ES, Michalski MP, Wille CM, Ryan MB. Effects of step rate manipulation on joint mechanics during running. Med Sci Sports Exerc. 2011;43(2):296-302.