Sole Searching—Why Educating Patients About Shoe Characteristics and Fit Matters
In this final installment of our 3-part series on advances in footwear technology, proper shoe fit, and the importance of sport-specific shoes, we decided to conclude by providing clinicians with a shoe fit tips to help educate patients on the most common terminology in footwear, as well as give patients an easy framework to guide them to find the most optimal shoes for themselves.
Talking to Patients About Important Shoe Fit Concepts
Sport-specific shoes are important because designs can address the biomechanical needs of that particular sport. In addition, it is vital to inform patients that the foundational concepts of shoe fit still apply, even for sport-specific shoes. Each individual patient must select the best shoe for their feet and their sport. Making them aware of the key terms as well as best practices may help them achieve the best fit to gain the greatest benefit of the emerging shoe technologies. Without proper fit, even the most innovative technology may not deliver the intended results.
Most patients are unaware that foot size can change for many reasons, such as aging, pregnancy, weight gain, injuries, soft tissue tightness, etc. They also may not know that one foot is often longer and/or wider than the other. About 60 to 70% of people have different-sized feet, due to natural asymmetry.1 Additionally, between 10 and 30% of the population has a longer second toe (Morton’s toe) compared to the hallux.2 This means one should determine shoe size from the longest toe, which may not actually be the hallux.
Another natural phenomenon that most patients are not aware of is the impact of leg length discrepancy (LLD), with the majority of these differences being slight and unproblematic. Only about 10% of the population has perfectly equal leg lengths.3 Patients are unaware that larger leg length discrepancies can lead to hip issues in the longer leg and knee issues in the shorter leg making finding the right shoe challenging. If the clinician provides heel lifts or custom orthotics, finding a specialty retailer to help the patient in selecting a shoe that can best hold and support the foot with enough depth throughout the becomes even more important. If a patient will be compensating for a leg length discrepancy by adding a lift under the foot of the shorter leg, they must also confirm that the rearfoot (heel counter) is deep enough to prevent heel slip (the sensation of stepping out of the shoes), and adjustability of the lacing to prevent undue pressure on the dorsum of the foot.
As podiatrists we know that widths are crucial, and the shoe should bend where the foot bends. We see that often folks tend to purchase a show in a larger size (length) to get enough width or depth to accommodate their feet. However, this strategy may result in a malalignment of the shoe geometry relative to their feet. If your foot does not bend where the shoe bends, then we have seen this lead to stress fractures, arthritis, nerve pathology, and even muscle weakness. We find that this is especially true with rocker profile and plated shoes. Thus, helping patients understand how shoe length and width impacts their shoe fit is another important discussion.
With the increase of rocker profile shoes, it’s first important to determine whether you want your patient using or avoiding this type of shoe. Rockers will shift work away from the foot and ankle. They are good for those with low calf strength, low ankle strength, and when there is a lack of mobility in ankle joint. In the right scenarios they may decrease overuse injuries or redistribute plantar pressures. But they may also shift the stressors more proximally to the hips, which may or may not be desirable.4,5
If you want the patient in a shoe with a forefoot rocker, such as in cases of hallux limitus or metatarsalgia, it is important to educate the patient on where the shoes should line up with the apex of the first metatarsophalangeal (MTP) joint.6 However, if a patient has balance problems including as a result of sensory loss of the feet, they may prefer shoes with flatter geometry to improve stability and sense of the ground. While there is no universal method to ensure correct placement of the ball of the foot at the rocker, the right size and width can make a huge difference. In our experience, the rocker should be directly under metatarsal heads to reduce motion and allow for easy push-off transition. In addition, having a secure midfoot fit (where the shoe feels like it cradles the middle of the foot) is just as important for optimal transition from initial foot contact to push-off.
“Stack height” refers to the thickness of the midsole cushioning material between the shoe upper that laces up around the foot and the rubber material outsole which provides traction and durability on the walking or running surface. “Heel-to-toe drop,” sometimes called “offset,” is the difference in height of the midsole between the rearfoot (center of the heel) and the forefoot (at the metatarsal heads). Discussing heel-to-toe drop is important because it can have an impact on your patients’ recovery and performance. For instance, we have noted that some pickleballers look for a higher drop shoe (8–10 mm), as it helps them stay in the ready position (with the ankles plantar flexed) better than a lower drop shoe. Generally, a lower drop shoe (2–4mm) will spare the knees but put more stress on the ankle, foot and lower leg, necessitating calf flexibility and strength, and ankle mobility. Conversely, a higher drop shoe will be easier on the lower leg (foot, ankle, Achilles, and calf) while directing more stress to the knees and hips.7
We have seen that many shoe brands now are moving to taller stack heights (over 35mm tall). While higher stack height can provide more cushioning and protection, there are a few things to consider when discussing these shoes with patients:
• High stack heights, especially those exceeding 40mm, can make the ankle joint less stable, potentially leading to sprains or other injuries, according to a study in Frontiers.8 On an episode of the Doctors of Running podcast, they shared that stack heights of 40mm + can put more strain in the hips and hamstrings.9
• Increased stack heights can affect running biomechanics, potentially leading to changes in stride length, step frequency, ankle stability and strength, and overall running style.
Time Out! Why Take the Time to Think About Shoe Characteristics?
Why should everyone take the time to think about the fit and feel of a shoe and which shoe characteristics are the most optimal for them? This is crucial (now more than ever) because there has been so much refinement of shoe geometries, midsole compositions, platform widths, rocker profiles that we can’t afford not to learn about it. The body is interconnected and improper fit or the wrong shoe leads to compensation and can impact.
While many specialty stores, such as running stores or comfort shoe stores, may be able to guide your patient in finding the best shoe for them, the majority of patients shop at either self-help stores, online, or stores with staff that haven’t been trained in specialty fitting. That is why we want to stress the importance of going to a specialty store to be properly fitted, taking the time to figure out what works best, and measuring both feet for shoe size annually.
Everyone responds to footwear technology and shoe geometries differently. What works for a professional athlete, or friends, or family members may not work as well for the patient. Also keep in mind that what worked and felt comfortable when the patient was younger may not feel the same as they age. Discussing normal variations over time and from person to person can go a long way in patients better understanding what shoe characteristics will or will not work for them. It is important to share with patients that shoe size and width can change for many reasons over time, including aging-related changes, injuries, weight gain, soft tissue tightness, and others.
It’s wise to impart that footwear influences the entire interconnected body. Most podiatrists are very familiar with various shoe fit tips, but we have included several here to incorporate into these conversations. Educate patients that shoes need to bend where the foot bends, and that it’s important to obtain the proper width, not just go up in numeric size. Sport-specific shoes are important because they are geared specifically for the biomechanical and traction needs of sport in consideration. We advise patients to try on shoes later in the day, after having been active, as this is likely when the foot will be at its largest/most swollen.
Additionally, trying on both shoes is important, as both feet don’t have identical geometry. Walking around the store will allow one to feel how the shoe transitions from heel to toe and how it holds the foot through gait. Black toenails and foot cramping are often signs recognizable to nonmedical professionals that shoes are too small or too narrow. Shoe laces should be roughly 1 inch apart. Sock thickness can contribute greatly to shoe fit, thus the socks worn when trying on potential shoes should be those that one expects to use with them after purchase. Performance-style socks may be more desirable in some cases, as they may be more anatomically constructed. Rotating between 2 pairs of shoes may help with injury prevention and muscle fatigue, and be sure to share with patients how often they should replace their shoes (based on mileage or length of time).
How Should Patients Evaluate Shoe Choices?
One of the best tools we’ve come across for helping people think about the most optimal shoe characteristics to consider when purchasing shoes was developed by Dr. Christopher Bishop (an Australian podiatrist) and team in 2020 called the RUN cat scale.10 There are 5 characteristics that they discuss. Here are some important details with thoughtful questions to pose with or to patients10:
1. Cushioning (both under the rearfoot and the forefoot). Currently, do your body and feet do well with softer cushioning or firmer cushioning? Keep in mind, what you felt was optimal in your earlier years may have changed as you age (such as age-related effects of thinning fat pads and arthritis, as well as changes in body weight, or arch integrity). This may alter your feeling of what constitutes optimal cushioning. While the high-energy return of PEBA midsoles can help absorb impact and reduce the load on inflamed tendons, including the Achilles and lower the stress on the musculoskeletal system, shin splints and stress fractures may do better with firmer cushioning.
Often patients in pain assume that a soft midsole will give them pain relief not knowing the excessive sinking creates more muscular demand causing more strain on the lower legs.9,11
2. Sole flexibility. How does the shoe roll and transition as you walk or run? Do you prefer more flexibility in the forefoot, or would you appreciate a rocker-profiled shoe that would allow you to roll off your big toe and not have to bend the ball of the foot as much? Often folks will try on one shoe without walking around to get a sense of how the shoe transitions from heel to toe, or how the shoe holds their foot as they move. The shoe should not have any downward pressure on the top of the foot (or lace bite) and the foot shouldn’t hang off the sides of the platform of the shoe.
3. Shoe stability. As you walk, or run, or imagine yourself going around a corner, do you feel like your ankle could roll? Alternatively, do you feel like the shoe is too stiff, and not allowing your foot to move comfortably?
4. Overall support. How does the shoe hold your midfoot? It is important to make sure there is no top of foot pressure. Is the heel counter holding your heel comfortably?
5. Toe room. Do your toes have enough room? Specifically, there should be enough room such that they do not touch the end of the shoe and there should be enough depth and volume to not squash the tops of the toes. Is the toe box roomy enough for your feet? There should be enough room in the toe box so that the tips of the toes are not touching the end of the shoe, the tops of the toes are not being squashed especially the toe nails, and the toe box is not too narrow causing the toes to be squeezed together against one another.
In Summary
It is our hope that this 3-part series on athletic footwear will has helped introduce, reinforce, update, and provide resources to help your patients get the best fitting shoes for their needs. Athletic footwear technology is rapidly advancing and increasing the footwear options and styles for our patients. It is important for the practitioner to be stay updated on athletic footwear trends and understand how these developments can affect the biomechanics and performance of your patients. Many common podiatric injuries can be caused or aggravated by wearing shoes which do not allow enough support, cushion, support, or stability for the activity, or are not specifically intended for that activity, such as wearing running shoes for pickleball. As our patient population ages, shoe selection is of paramount importance to keep them active and to help reduce falls and other injuries. The uppers, midsole material and design, and the outer sole for traction are all essential components with shoe selection. By consulting all three of the articles in our series, you can work to empower yourselves and your patients to have a solid foundation to navigate the wide variety of contemporary shoe materials, designs, and mechanical features.
Dr. Dutra is an Assistant Professor at Samuel Merritt University College of Podiatric Medicine. He is a Podiatric Team Physician at the University of California, Berkeley. He is the Clinical Director of Special Olympics Healthy Athletes Fit Feet and a Past President of the American Academy of Podiatric Sports Medicine.
Dr. Hill is an Associate Professor and Manager of Motion Analysis Research Center at Samuel Merritt University.
Ms. Wong is the Certified Corporate Wellness Specialist and Business Development Representative at New Balance.
References
1. Buldt AK, Menz HB. Incorrectly fitted footwear, foot pain and foot disorders: a systematic search and narrative review of the literature. J Foot Ankle Res. 2018 Jul 28;11:43. doi: 10.1186/s13047-018-0284-z. PMID: 30065787; PMCID: PMC6064070.
2. Potu BK, Saleem BMM, Almarabheh A. Prevalence of Morton’s toe and assessment of the associated risk factors: a cross-sectional study. Eur J Anat. 2023; 27(6):717–22.
3. Gordon JE, Davis LE. Leg Length Discrepancy: The Natural History (And What Do We Really Know). J Pediatr Orthop. 2019 Jul;39(Issue 6, Supplement 1 Suppl 1):S10-S13. doi: 10.1097/BPO.0000000000001396. PMID: 31169640.
4. Klein M. Footwear science: rocker soles. Doctors of Running. Available at https://www.doctorsofrunning.com/2017/05/footwear-science-rocker-soles.html#:~:text=I%20have%20discussed%20toe%20spring,moment%20arm%20have%20been%20changed. Accessed Sept. 29, 2025.
5. Munim F, Jor A, Pollen TN, et al. Effects of rocker-bottom shoes on the gait biomechanics of running and walking: A systematic review. Gait Posture. 2025;121:44-63. doi:10.1016/j.gaitpost.2025.04.019
6. Kurnianto RR, Hijmans JM, Greve C, Houdijk H. Rocker shoe apex settings do not induce anticipatory changes in foot progression angle before the onset of the second rocker. Gait Posture. Published online September 2, 2025. doi:10.1016/j.gaitpost.2025.09.001
7. Dutra T. How does heel-to-toe drop in running shoes impact heel pain? Podiatry Today. 2022; 35(11):14-20.
8. Kettner C, Stetter B, Stein T. The effects of running shoe stack height on running style and stability during level running at different running speeds. Front Bioeng Biotechnol. 2025 Feb 21;13:1526752. doi: 10.3389/fbioe.2025.1526752. PMID: 40059889; PMCID: PMC11885301.
9. Doctors of Running. Should Running Shoes Over 40mm Be LEGAL? Do Shoes Need Yearly Updates? Max Stack NOT Needed? Available at https://www.youtube.com/watch?v=ZgUZ0RDNr2E. Posted 2025. Accessed Sept. 29, 2025.
10. Bishop C, Buckley JD, Esterman AE, Arnold JB. The running shoe comfort assessment tool (RUN-CAT): Development and evaluation of a new multi-item assessment tool for evaluating the comfort of running footwear. J Sports Sci. 2020 Sep;38(18):2100-2107. doi: 10.1080/02640414.2020.1773613. Epub 2020 Jun 6. PMID: 32508250.
11. Sanchez C. The ultimate guide to running shoe foams. RunRepeat. Available at: https://runrepeat.com/guides/running-shoe-foams-guide. Accessed September 30, 2025.
Additional References
13. Azis M. Understanding Foot-Body Connection & How It Shapes Overall Health. Available at https://livepositively.com/understanding-foot-body-connection-how-it-shapes-overall-health/ . Positively Live. Published May 11, 2025. Accessed Sept. 29, 2025.
14. Michael. What is stack height? Running Warehouse. Available at https://www.runningwarehouse.com/learningcenter/gear_guides/footwear/stack-height.html?srsltid=AfmBOoo5keqc3y8hgnctuSsHT5wAAu4RTYjU0zKPqRGAxjeKZvJPGYE9 . Published Aug. 29, 2025. Accessed Sept. 29, 2025.
15. Henry Ford Health Staff. Have A Long Second Toe That's Causing Pain? Here's How To Fix It. Henry Ford Health. Available at https://www.henryford.com/blog/2022/12/long-second-toe . Published Dec. 7, 2022. Accessed Sept. 29, 2025.
16. Subic J. Heel to Toe Drop: The Ultimate Guide. Available at https://runrepeat.com/guides/heel-to-toe-drop . Published Sept. 28, 2025. Accessed Sept. 29, 2025.
