When I first caught the title of this ‘study’ my initial reaction was add it to the massive pile of backlogged articles that I need to comment on! I have litigated the running economy and foot strike and shoe type enough times: here, here, here, here, here, here, here, here, here, here and here). However, this ‘study’ was different as it was a review of the evidence on the topic and it raised an issue that I have been harping on about for years. There have been many studies on this topic and if you are promoting a particular agenda or narrative you can cherry pick a group of studies to make your point and hope your ‘audience’ are not aware of a body of literature that contradicts your agenda or narrative. Lots of people do just that. Of course, that approach is an epic fail, not cool and intellectually dishonest.
When there is a body of literature on a particular topic, it is then time to start doing systematic reviews and meta-analyses of all the studies and their data, especially if some of the results are conflicting. Most importantly, the quality of the methodology used in individual studies is also taken into account. This new review, was one step short of being a formal systematic review, but was a narrative review:
The effects of foot strike on running economy in distance runners: a narrative review
Robin Nichols, Courtney Germano, Morgan Burke, Kayley Nolan, Kim Youngs-Grand & Joe Girard
Physical Therapy Reviews 14 Jul 2016
Background: Successful distance runners usually demonstrate efficient running economy. Running economy is comprised of many variables, including foot-strike pattern. It is unknown if foot strike pattern has any effect on running economy.
Objective: The purpose of this narrative review is to examine recent evidence on the effect of foot strike on running economy in distance runners.
Methods: This narrative review indexed the following databases: Medline, CINAHL, SportsDiscus, and PubMed. Articles were included if the study examined correlations or relationships between foot strike pattern and running economy.
Results: Five articles satisfied the eligibility criteria and were included in this review. Results examining the effect of foot strike on running economy were varied. Two studies demonstrated a significant effect of foot strike on running economy: One study found that midfoot and forefoot strikers were found to have better running economy compared to rear foot strikers (p = 0.019). Another study showed that rear foot strikers demonstrated superior running economy with 5.4% and 9.3% lower VO2 (p < 0.05) at 11 km/h and 13 km/h, respectively. Three studies showed no significant effect of foot strike on running economy. Conclusion: The reviewed studies collectively suggest that foot strike pattern alone is not a determinant of running economy. Further research is needed to discover what particular role or advantages individual foot strike patterns may have on running economy and what other factors and characteristics correlate with running economy and performance.
The conclusion from the available literature is clear: “The study found that midfoot and forefoot strikers were found to have better running economy compared to rear foot strikers. Another study showed that rear foot strikers demonstrated superior running economy … Three studies showed no significant effect of foot strike on running economy.” There are more studies that have been done that the authors did not include, mostly conference abstracts that have not yet been published in full, so they quite rightly did not include them. However, the pattern of results from these would not change the conclusion of the above review.
As I have repeated numerous times, there is no systematic advantage of one foot strike pattern over another when it comes to running economy. The advantages of one over another for a particular individual (ie subject specific) will be related to a number of factors. To blanket suggest that one is better than another is an epic fail as it does not take into account the conflicting results of the evidence and the studies that found no differences. To use the model of ‘subject specific response’ will fit with that conflicts in the available evidence.
I have already suggested (The importance of joint moments in running injury risk and running economy) that a key in that subject specific response is our anatomical variation. As all our faces and other anatomical features vary, so do the joints surface orientation and joint axis orientation vary which will affect the lever arms that tendons have (and there is good data on those variations). That variation in lever arms will affect how hard a muscle needs to work (ie economy) and the energy return from stored energy (ie economy). For some that will be heel striking, for others that will be midfoot striking and for others that will be forefoot striking.
As always, I go where the evidence takes me until convinced otherwise ….and there are no systematic advantages of one foot strike pattern over another when it comes to running economy.
Nichols, R., Germano, C., Burke, M., Nolan, K., Youngs-Grand, K., & Girard, J. (2016). The effects of foot strike on running economy in distance runners: a narrative review Physical Therapy Reviews, 1-6 DOI: 10.1080/10833196.2016.1193970