Biomechanics Week 13 Responses

Response 1: Scott W

I found the first article very interesting as I have spoken about the importance of a person’s gait and even shoe wear in previous weeks. The first part that grabbed my attention was “In addition, the smaller peak dorsiflexion after mid-stance (Figure 2A) may suggest a stiffer ankle complex from heel strike to mid-stance in the open-toe shoes and barefoot compared to shoes.” (Zhang, Paquette, Zhang, 2013). I was not shocked about the barefoot comparison having an effect on the ankle, but I will say I was intrigued by the open toe having an effect. Later in the article, the author shares how the research concluded the role of the heel in the modern running shoes plays a significant role in the overall biomechanics of an individual’s gait. After having read that, I will say that I have not spent a significant amount of time looking into that portion of an open toe sandal. However, I do know that there are certain shoes (women’s fashion) that have a built up heel around an open toe shoe. I have recently completed a gait analysis running test to examine my own gait. After completing a gait analysis test (which was really eye opening as I never realized that I swing my right left out close to 30 degrees) he recommended that I wear a shoe with a significant drop in my heel. 

Response 2: Delania A.

After reading the article, “Gait modifications to change lower extremity gait biomechanics in runners: a systematic review” I was familiar with most runners not being able to return to their sport due to measures including rearfoot eversion, vertical loading rate and foot strike index (Napier et al., 2015). It is very important that runners wear the proper shoes, the main thing they want to look for when looking for running shoes is to get shoes that support their foot and are light while they are running. According to Napier et al (2015), most running injuries occur due to orthotics, shoes, the absence of shoes, as well as changing surfaces. The changes that occur in a runner hip from a kinematics aspect were very interesting to me. Hip angle at initial contact showed decreased flexion in those people who ran forefoot (people who run on balance) and barefoot (Napier et al., 2015). One thing that stood out to me the most was the research discovery during the vertical impact peak. During the vertical impact peak the step length and step frequency manipulation and peak-positive acceleration feedback was reduced (Napier et al., 2015). A theory was tested in order to reduce vertical impact peak by including hip adduction angle retraining, and foot strike manipulation and pose technique were factors that did reduce vertical impact peak (Napier et al., 2015). The effects of gait modification on kinetic measures had an impact on many things. One thing that was affected by gait modification on kinetic measures was the significance that impact loading had as the injury risk factors (Napier at al., 2015). 

Response 3: Kendra C.

  I remember growing up I never really wore shoes when I played outside with the other neighborhood kids, or if I did wear something, they were flip flops but just were thrown off as soon as I got outside. I felt like putting shoes on was a waste of time and that they just got in my way. Previous research studies suggest that wearing lightweight and minimally supportive footwear such as flipflops and sandals during childhood has an effect on foot arch development. Although minimal open-toe footwear (e.g., flip-flops, sandals) worn at a young age may be more beneficial in developing normal foot arches in adulthood compared to closed-toe shoes, their long-term effects in adult populations are still relatively unknown (Zhang et al., 2013). What I found interesting is when the article was talking about how a number of studies have investigated the biomechanical implications of walking in flip-flops compared to barefoot and/or closed-toe footwear. The article showed that walking in flip-flops resulted in a shorter stride length, a shorter stance time, a smaller braking ground reaction force (GRF) impulse, and a larger ankle contact angle compared to running shoes in both men and women (Zhang et al., 2013). The results of this article were also interesting to me. I have not really thought much about the difference when it comes to the gait biomechanics of walking in flip flops, sandals, barefoot, and shoes

Response 4: Adam Jent

As I began to read the various articles posted this week, I was initially drawn to this particular topic.  Immediately, Zhang, Paquette, and Zhang (2013) presented an argument that states the early childhood habits regarding the type of footwear primarily worn can directly impact the structural qualities of the foot.  What I did not expect to follow was a claim that footwear like sandals and flip-flops, while being light weight and containing minimal support, actually provide the benefit of helping a young child in arch development.  As a child, I rarely wore sandals or flip-flops and could often be found running around in basic tennis shoes.  I now have a better appreciation for a possible contributing factor to the minimal arch I have had throughout childhood and now into adulthood.  Although I do not generally have any issues due to low arches, I am curious if my situation would be the same had I been placed in these other types of footwear as a child.

Response 5: Josh Young

The first article I chose was “A Comparison of Gait Biomechanics of Flip-Flops, Sandals, Barefoot and Shoes”. I chose this article because I treat a lot of feet/ankle injuries. Starting out, the article mentioned that sandals and flip-flops are light-weight and comfortable (Zhang, Zhang, & Paquette, 2013), to which I completely agree. Adding to that, however, I am from Houston, TX and it is very hot and humid here for a large part of the year, so sandals and flip-flops are a common shoe type because it is a cooler option than keeping your feet in closed-toe shoes for long periods of time. Right or wrong, many people here wear some sort of open-toe shoes, self-included. Biomechanically, it appears that closed toe shoes are the better option. They allow the ankle to be more dorsiflexed at contact, allow for more plantarflexion, and provide more cushioning to absorb shock (Zhang, Zhang, & Paquette, 2013). It makes sense, then, that wearing a closed toe shoe is important when doing any kind of activity with impact. I found it interesting that shoes had a lower peak propulsive ground reaction force than the other three options (Zhang, Zhang, & Paquette, 2013). I would have thought that as supportive as shoes are, there would have been more GRFs. I had to read the explanation as to why the GRFs were lower several times before I understood it. Shoes allow for the highest contact angle (dorsiflexion) between the four options. Barefoot has the lowest contact angle (relatively flatter foot) than sandals or flip-flops, but compared to shoes they have a flat contact angle as well. Because of this lesser contact angle, more GRFs are needed to allow for the heel-to-forefoot translation during walking. After reading this article, when I think about it, I realize that I actually struggle to walk in flip-flops. It seems harder to stay balanced and I definitely can not walk as fast.