Another aspect that improves speed is enhanced geometry. Various enhancements, such as extended heels, asymmetrical midsoles, or no heels, exist. However, we'll focus on one in particular, known as the "swing effect improvement." This type of geometry requires increased shoe height to accommodate a rigid plate. The plate can be flat and placed over a stiff material, as seen in Nike shoes, or shaped like a checkmark, as in Adidas adizero shoes. Both designs work in a similar manner. When pressure is applied to the forefoot, it propels the heel, enhancing running efficiency and speed over long distances. Yet, this improvement has a downside—shoes with higher stacks compromise stability. If your foot isn't positioned neutrally, there is an increased tendency to bend towards one side. Therefore, shoes in this segment are not suitable for runners lacking developed stabilizing muscles or those with pronation variations.