blisterWhile typically thought as a minor nuisance injury, blisters of the feet are among the most common injury suffered by athletes and can lead to more serious injuries.

Athletes should choose their footwear and socks carefully. The first defence against friction blisters is proper fitting socks and shoes. Numerous high-tech sock choices exist, including the ones which lift perspiration off the skin like a “squeegee”, while others wick perspiration, and some have anatomically placed padding to increase cushioning.

The capacity to control perspiration build up around the foot and dissipate friction is not necessarily inclusive for technical socks. In fact, three of the most popular fibres used in the construction of technical socks possess good moisture management properties but also exhibit higher coefficient-of-friction. This friction may be minimised by sock designs that include anatomically padded zones or double layering.

Friction and torque created during athletic activity generate shearing forces between the skin and sock/shoe surfaces. These forces when absorbed by the skin can accumulate – weakening the bonds between skin cells which can lead to the development of a friction blister. Typically, these forces are below the threshold of most athletes. Various sock designs are available to minimise these forces; the most common is the anatomical placement of dense padding which cushions areas of the foot prone to blisters (such as the toes, forefoot, and heel). Also popular are double layer socks which attempt to divert friction away from the skin and shift it outward between the sock’s double layers.

For those individuals who frequently suffer from blisters between toes, they can use anatomical toe socks which can minimise the friction and rubbing between toes during running. Unfortunately, toe socks can be awkward to put on and take off; they can feel somewhat unnatural because of the spreading toes with two layers of material between each of them.

Athletes should be aware of their individual sock needs which include fitting, durability, leg height, cushioning, support, thermal properties, and moisture management. Avoid those with obvious pressure points; select properly fitted socks and carefully inspect any new sock on the inside for potentially injurious sock seams. When considering the construction of the sock, select only the socks made with flat knit toe seams and Y-heels, or those with vector heel pocket designs. Socks, like shoes, should be size-fit to your foot because improper fitting can lead to blisters. Avoid overly tight or loose fitting socks. Ill fitting and very tight socks may bind the toes, while socks which are too loose can lead to harmful wrinkles, capable of pinching the skin and causing blisters.

During warm weather, the accumulation of heat around the foot can contribute to the formation of blisters. Many socks have thin insteps under the arch. Some sock brands offer ventilation panels under the arch and/or the base of the toes to help dissipate heat generated during athletic activity.

Healthy skin is less likely to develop friction blisters. Athletes should avoid dehydration especially when training during warm weather. Healthy well hydrated skin can tolerate more stress before breaking down and developing a friction blister.

No discussion about socks is complete without some attention to shoe fitting. Proper fitting of any new shoe should be done with appropriate consideration to the sock thickness. It is also important to carefully inspect new shoes for manufacturing flaws. You should check the inside and outside for prominent seams or stitching, abrupt fabric edges, fabric wrinkles, malformed thermal plastic parts, misaligned lace eyelets, tongue or excess fabric – all of which could lead to hot spots or blisters.