Summer is the time of year that I become horribly unpopular amongst my athletes. One of the things that many people use to identify summer with, flip flops, are back in season — and as quickly as they make their appearance, I tell my patients to put them back in the closet. Flip flops can be a big culprit of leg pain, hip pain, shin splints, back pain and so much more. So, yes, flip-flops are bad for you.
Shoes are designed to perform two basic functions (among other things): To provide shock absorption; and to provide a solid, stable surface that your foot can push off from, essentially providing stability. Flip-flops, however, provide neither shock absorption nor stability. They are basically just covers for the bottoms of your feet.
Over the years, makers of flip-flops have tried to add stability and shock absorption into them. Some of the more expensive brands come with an arch support and some come with more cushion. Yet, neither generic arch support nor increased foam provides the same support and shock absorption that a sneaker does. Without your shoe being able to perform these two main functions, you could cause yourself pain, not only in your foot but up your entire leg, into the knee, hip and back as well.
Without a proper arch and without proper ability to absorb shock, your foot is forced to move differently and the ligaments, bones and muscles in the foot are forced to work harder than they are used to. Changing something, even slightly in the foot changes how the muscles and the ligaments function in the foot — and this change cannot come independently. Changing one thing affects the joint next to it, which will then affect the joint next to that. Therefore, the knee and the surrounding ligaments and muscles, must make a change in order to compensate for the changes made at the foot. This type of pattern continues up the chain to your hip and low back, making small subtle changes that might not affect you right away but can cause you problems later on or exacerbate problems that are already there. Unfortunately, these small changes will be something your body does naturally that you are not aware of so it's not something that you can consciously undo.
Now, I realize that telling the average person to not wear flip-flops in the summer is not a realistic statement. But, the best thing you can do for your legs and back is to wear flip-lops in moderation. If you know that you are going to be sitting on the beach all day, then by all means, wear your flip-flops. If you know that you are going to be standing for long periods of time, then it is probably best to leave the flip flops at home and wear sneakers and give your feet, knees, back and hips some much needed support. Walking in flip-flops for long periods of time is also not advisable. However, for shorter walking periods or if you know that you are going to be sitting for a while, flip-flops won't cause any major damage.
Taking small steps to give your joints support will allow them to function pain-free for a longer period of time. Packing the sneakers away along with the winter sweaters is not advisable for a fun, pain-free summer.