The flip-flop research involved 39 male and female graduates. They were videoed while walking in flip-flops and in athletic shoes. The researchers compared the length of people’s stride and limb angles when people wore the different footwear. They discovered that flip-flop wearers took shorter steps, gripped more with their toes and moved their ankles in a wider angle. All of these changes to our walking style cause unnatural shocks to our joints. This can create stresses which can lead to serious injury if they are repeated over a long period of time. Estimates are that the average person takes 15,000 steps each day. Even small, unnatural changes to a healthy walking style can be multiplied thousands of times if we wear flip-flops all day. The researchers advised wearing flip-flops for short periods of time only