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While Strike Index is a good measure of Foot Strike, it requires sophisticated equipment to measure the pressure the foot makes as it lands. A simpler approach is to look at the angle of the foot as it touches down, called Foot Strike Angle (FSA). It is practical to evaluate FSA with [[High Speed Video Analysis]]. A study compared the two approaches and found there was a good correlation between Strike Index and FSA<ref name="AltmanDavis2012"/>. Note in the graph below the wide range of strike indexes for RFS, from nearly 0 (the extreme back of the heel) to close to the 33% mark, which is well in front of the heel bone.
[[File:Foot Strike Angle.jpg|none|thumb|500px|A graph of Foot Strikes, with each point showing Strike Index against Foot Strike Angle<ref name="AltmanDavis2012"/>. A Foot Strike Angle of 0 degrees means the foot is level with the ground on first contact. The color coding indicates the visual categorization of the Foot Strike.]]
=Measuring Evaluating Your Foot Strike=It seems intuitively obvious that a runner will know how their foot lands. However, it seems that runners are actually relatively poor at evaluating their foot strike. A study of 60 runners found that only 70% knew their foot strike<ref name="GossLewek2015"/>, while another study found that only 44% of recreational runners and 57% of collegiate cross-country runners knew their foot strike<ref name="Bade-2016"/>. This is in line with a study of 87 runners that showed only 69% were correct in their identification of their foot strike<ref name="Goss-2012"/>. Personally, I suspect that the extremes of foot strike are relatively easy to distinguish. A forefoot runner whose heel never touches the ground is pretty obviously a forefoot runner. Likewise, many runners are quite obviously extreme heel strikers. Between those extremes that becomes far more uncertainty, and a more objective measure becomes valuable. I think there are a few options for evaluating your Foot Strike:* High speed video can be quite effective, and the cameras are becoming far more accessible. The iPhone 6 and later will do 240 frames per second, which is enough to give a good evaluation of your foot strike.* There are a number of [[RunScribeRunning Sensors]] make Footpods that can measure will detect your Foot Strike. I've found [[RunScribe]] to be quite accurate when compared with high-speed video, though I've also had promising results from [[SHFT]]. * A common approach has been to look at the wear pattern on the sole of your running shoes. However, I've come to believe that this is extremely misleading as well as the movement wear on the bottom of your shoe has a far more to do with abrasion than it does pressure. For instance, I make initial contact with the ground with my heel, and when descending steeply, I tend to scrape the extreme edge of the heel. So, if you look at the outsole of my shoes you'd conclude that I am an extreme heel strike runner, but that's not an accurate conclusion.* Perhaps the cheapest, easiest, and most useful approach however is to look at how the cushioning of your running shoes degrades. I've found consistently that my running shoes become compressed under the ball of my foot after , which indicates this is the area of greatest loading. I have relatively little compression over the rest of the shoe, including no real compression under the heal, which suggests that I am a "proprioceptive heel strike" runner. I've found that I can see this degradation of the shoes cushioning most easily in the removable insole.[[File:Insole Wear and Foot Strike.jpg|none|thumb|300px|This is an insole where I've marked the area of compression, which is under the ball of my foot. It's hard to photograph the compression, but the it's quite obvious to the touch.]]
=Foot Strike science=
The optimum Foot Strike is unclear given the available evidence.
=References=
<references>
<ref name="GossLewek2015">Donald L. Goss, Michael Lewek, Bing Yu, William B. Ware, Deydre S. Teyhen, Michael T. Gross, Lower Extremity Biomechanics and Self-Reported Foot-Strike Patterns Among Runners in Traditional and Minimalist Shoes, Journal of Athletic Training, volume 50, issue 6, 2015, pages 603–611, ISSN [http://www.worldcat.org/issn/1062-6050 1062-6050], doi [http://dx.doi.org/10.4085/1062-6050.49.6.06 10.4085/1062-6050.49.6.06]</ref>
<ref name="NiggBahlsen1987">B.M. Nigg, H.A. Bahlsen, S.M. Luethi, S. Stokes, The influence of running velocity and midsole hardness on external impact forces in heel-toe running, Journal of Biomechanics, volume 20, issue 10, 1987, pages 951–959, ISSN [http://www.worldcat.org/issn/00219290 00219290], doi [http://dx.doi.org/10.1016/0021-9290(87)90324-1 10.1016/0021-9290(87)90324-1]</ref>
<ref name="KellerWeisberger1996">TS Keller, AM Weisberger, JL Ray, SS Hasan, RG Shiavi, DM Spengler, Relationship between vertical ground reaction force and speed during walking, slow jogging, and running, Clinical Biomechanics, volume 11, issue 5, 1996, pages 253–259, ISSN [http://www.worldcat.org/issn/02680033 02680033], doi [http://dx.doi.org/10.1016/0268-0033(95)00068-2 10.1016/0268-0033(95)00068-2]</ref>
<ref name="KasmerLiu2013">Mark E. Kasmer, Xue-cheng Liu, Kyle G. Roberts, Jason M. Valadao, The relationship of foot strike pattern, shoe type, and performance in a 50-km trail race, Journal of Strength and Conditioning Research, 2013, pages 1, ISSN [http://www.worldcat.org/issn/1064-8011 1064-8011], doi [http://dx.doi.org/10.1519/JSC.0b013e3182a20ed4 10.1519/JSC.0b013e3182a20ed4]</ref>
<ref name="Kasmer-2014">ME. Kasmer, JJ. Wren, MD. Hoffman, Foot strike pattern and gait changes during a 161-km ultramarathon., J Strength Cond Res, volume 28, issue 5, pages 1343-50, May 2014, doi [http://dx.doi.org/10.1519/JSC.0000000000000282 10.1519/JSC.0000000000000282], PMID [http://www.ncbi.nlm.nih.gov/pubmed/24149763 24149763]</ref>
<ref name="Bade-2016">MB. Bade, K. Aaron, TG. McPoil, ACCURACY OF SELF-REPORTED FOOT STRIKE PATTERN IN INTERCOLLEGIATE AND RECREATIONAL RUNNERS DURING SHOD RUNNING., Int J Sports Phys Ther, volume 11, issue 3, pages 350-5, Jun 2016, PMID [http://www.ncbi.nlm.nih.gov/pubmed/27274421 27274421]</ref>
<ref name="Goss-2012">DL. Goss, MT. Gross, Relationships among self-reported shoe type, footstrike pattern, and injury incidence., US Army Med Dep J, pages 25-30, PMID [http://www.ncbi.nlm.nih.gov/pubmed/23007933 23007933]</ref>
</references>