Less black toe nails while running
Anatomical last shape and half European sizes
Developing the Runnertune last shape, it was our goal to provide the necessary space for the foot and especially the toes. At the same time we wanted to keep the foot firmly inside the shoe. Our lasts are based on the European size system - Runnertune running shoes come in half sizes from 35 to 47.5. This means a step of 3.33 mm per half size.
Why European sizing?
Worldwide no generally accepted shoe sizes exist. There are various size systems that differ regarding the length per size step. Almost all running shoes are based on the US sizing system that is designed for a difference of 4.23 mm per half size. Our opinion is that this is too imprecise though. That´s why we stick to the European size system that means a difference of 3.33 mm per half-size. Spoken in absolute terms 0.9 mm difference per half size between the two size systems sounds not that much. In relation and compared to other running shoes, however, our size gradation bears almost 20 percent more fitting accuracy.
Toe box with sufficient space
We gave a lot of thoughts to the Runnertune last shape design in order to transfer the requirements of a human foot onto the last form in the best practical manner. That´s why we decided not to develop a pointed toe area that would only satisfy fashion purposes. A running shoe is a tool that must provide the foot with the necessary space so that it can bring up its full potential. Due to our last design the toe box is made sufficiently large. Thus the toes are not squeezed and the risk of back toe nails is minimized.