Now that we are well and truly into the summer season I thought I would use this blog post to look at the impact of flip-flops on your lower back and pelvis. Although for the brave flip-flops are a mainstay for some people throughout the year many of us only put them on during the summer months.
Now, not focusing on the types of problems they specifically cause with feet like hammer toe, bunions not to mention fungal infections – although that may be enough to put most people off wearing them. Instead I’m focusing on how they can change the way you walk and thereby how it loads the spine.
The key changes are altered gait due to:
-It being a supeflat shoe
-It has minimal cushioning for heel strike
When you wear a flat type of footwear the main change usually occurs in the arch of the foot, really it depends on the biomechanics of your foot, so if you have a high or low arch it may affect you more. It also usually affects you more if you have flat feet or have been told that you over-pronate.
Heel strike is when our heel makes contact with the ground, this means it goes very quickly from zero force to almost all of the force being carried by the heel before the midfoot and then the toes come into contact with the ground to dissapate the forces and prepare to spring off for the next step. When we walk with shoes on we actually take longer strides as the shoes provide cushioning, when we are barefoot we take shorter strides as it results in less force going through the heel. So flip flops encourage us to walk with longer strides when really we should be taking shorter ones due to the reduced cushioning.
Sometimes you see people who are walking in flip flops and there is a distinctive slapping sound as they are (sometimes not conciously) avoiding the heel strike and allowing the midfoot and forefoot to take more of the strain. Whereas when people run barefoot they commonly avoid a heel strike, when we walk, even barefoot we should have a heel strike. This and the other changes in gait can have a big impact on the way the forces are transferred up the legs and into the pelvis and spine. This results in compensations and eventually secondary conditions such as pain/discomfort or isolated cases of hip pain or low back pain.