adidas' BOOST™ technology combines comfort with enhanced bounce-back, resulting in more energy at take-off in each step. BOOST™ cushioning is softer, and returns more energy, than conventional EVA technology. Until now, comfortable has meant "soft", while energy return has meant "hard". As a result, performance shoes have either been comfortable or fast. BOOST™ technology offers both. It is light, air permeable, and was designed to form to the shape of your foot for a more natural fit.