A Little Bit About Feet and Footwear
Arches in the Foot
The arches of the foot are formed by the boney structure and reinforced by the ligaments muscles and tendons of the foot. The arches of the foot are a little more than three dimensional half domes. The anatomy and shape of the arches can influence the types of injuries that a person is predisposed to.
The arches in the foot allow for shock absorption through the mobility they allow for. The medial longitudinal arch actually allows the whole leg to twist inward a small amount with each step. With that, the muscle, ligament and joint fibres in the arch are gently stretched. In addition, the knee joint is very slightly twisted and the hip and pelvis are also twisted as the movement travels up the limb. Several muscles in the leg contract in order to resist and minimize this twisting up the leg. This controlled twisting at each joint in the leg is subtle and is an important part of healthy movement. Each of these muscles, ligaments and other soft tissues that control the twisting can be injured when there is enough force or if excessive twisting goes on long enough. Assisting with control of the foot arch and the whole leg twisting motion is one of the main functions of orthotics.
Adaptation and Footwear
Each muscle and tissue in our body is accustomed to a specific length and the amount of strength needed for it’s usual activities. Abrupt changes in activities and the demands on our muscles can cause soreness and fatigue if they exceed the muscle’s adaptation potential. Take heel height for example. Consider how the calf muscles and their attachment to the Achilles tendon will shorten with a high-heeled shoe. Conversely, the Achilles and calf muscles will be stretched when asked to function in a flat shoe if they are adapted to a high heel. This case clearly demonstrates the idea that your calf muscles become adapted to a specific length based your typical footwear. If the accumulated stresses and micro damage from each day’s activity are not mended, a backlog happens and eventually pain results. This occurs when changes in activity or footwear exceed the adaptation potential of the muscle or soft tissue. Footwear that doesn’t guide your foot in a way that it is used to will accelerate this process by putting extra strain on muscles and connective tissue that holds the foot and leg stable. This is why many orthotics providers will encourage you to slowly transition into your new orthotic over a period of two to three weeks.
In taking this example one step further consider this: None of us would decide to sign up for a marathon next weekend because it is important to train for this type of event unless you want to get hurt. Your tendons, muscles, and even bones need to adapt during months of training in order to perform successfully and without injury in a marathon. If you are planning a hiking holiday but you typically lead a sedentary lifestyle then you had better consider your itinerary and start off slowly and build up your tolerance over the duration of your holiday. Or better yet, you should set up a training plan just like a runner planning a marathon would. Not quite as extensive, but a plan over several weeks to condition your body and prevent injury while on the trip. It may also be wise to consider purchasing a new pair of running shoes or hiking boots at the beginning of your training. Old shoes will have lost their support because the foam begins to break down. Running shoes more than a year old, especially if they have been kept in the heat will have lost a considerable amount of their inner support even if they haven’t been worn that much. Shoes worn indoors will often appear to be in good shape, but if your feet or knees are beginning to ache, a change of shoes is the first strategy.
Laurie Bickerton, FCAMPT Physiotherapist
Laurie Bickerton is a FCAMPT physiotherapist practicing at Rebalance Sports Medicine in downtown Toronto.