Shock absorbing insoles help to keep feet and lower limbs healthy and protected.
Why is shock absorption important when running? Each time your foot hits the ground it comes to a sudden stop, this stopping collision causes a rapid shockwave, caused by your body weight and the resistance of the hard ground below it, to travel through your foot and upwards throughout the body as the force dissipates.
It is estimated that the collision generates a force between 1.5 to 3 times your bodyweight, depending upon where on the foot you hit the ground.
Imagine the average man weighing around 83.6kg (roughly 184lbs) according to the Office for national statistics in the UK. Now imagine your foot being hit by 276lbs-552lbs of force 1,000 times (the average number of strides it takes to run a mile).
Good running technique will lead to the force generated being on the lower-end of the estimate, whereas bad technique will lead to force generation on the high end of the estimate. Heel striking increases the force, whereas forefoot striking reduces it.
Shock can cause damage to the ligaments and tendons in the feet. Shock can also cause minute and lasting damage to the tendons and ligaments found in other lower limbs as well including your knees. One of the most common injuries caused by shock resonating from the feet to the knees is patellar tendinitis. There is sufficient evidence that has proven that continual shock from running can cause microscopic damage to the patellar tendon found in your knee. If the shock decreases or ceases so that the body is once again able to heal itself sufficiently, patellar tendinitis usually goes away however stopping running or decreasing usage of their feet or knees is usually not an option for athletes. This is why so many athletes choose to wear shock absorbing insoles to help minimise the shock and damage they are doing to their knees without having to give up on the sport that they love.