How to evaluate Cushioning performance of Sports shoes?
Compression set is a key property to consider when choosing materials for footwear, especially for the midsole, which provides cushioning and shock absorption. The compression set of a material refers to the extent to which it permanently deforms under stress and fails to return to its original shape once the stress is removed.
Foam is commonly used in footwear due to its comfort and shock-absorbing properties. However, different types of foams have different compression set properties. For instance:
- Polyurethane (PU) Foam: PU foams generally have good compression set properties, meaning they are resistant to permanent deformation under repetitive stress. They are often used in high-end running shoes and other athletic footwear. PU foam can offer superior cushioning and durability, but it's also slightly heavier than other types of foam.
- Ethylene-Vinyl Acetate (EVA) Foam: EVA foam is lighter than PU foam and also has good compression set properties, making it a popular choice for running shoes and other athletic footwear. However, EVA foam may not be as durable as PU foam, and it might not provide the same level of cushioning.
- Memory Foam: This foam type conforms to the shape of the foot, providing personalized comfort. However, memory foam tends to have a higher compression set, meaning it may permanently deform over time and lose its cushioning properties.
When designing footwear, it's crucial to consider the intended use of the shoe. For example, a running shoe needs to resist high repeated stresses and should therefore have a low compression set. In contrast, a dress shoe that won't undergo the same amount of stress might be fine with a higher compression set.
Ultimately, the compression set of foams in footwear is a balance between comfort, durability, and performance. Advanced material science is continuously improving these materials, providing footwear designers with a greater range of options to optimize for different use cases.
Why is the Plaeto Midsole cushioning system superior?
Plaeto uses a proprietory cushioning system, Plaeto365, that has been designed for long term durability and comfort. Plaeto365 has a Compression set of less than 7% in lab tests versus a 40%+ compression set for EVA foams used by other shoe brands. It has been seen from our experience that EVA foam bottoms out after about 400 Km of use, while Plaeto365 midsole maintains the same performance at the end of 2000 Km of use. An average Indian child puts in over 2000 kilometers of use annually in her shoe.
Plaeto has received on-ground validation of this superior cushioning performance from Kiran Verma, who is on a 21000 Km walk across India in Plaeto Shoes.