Go from pack runner to leader of the pack in the Newton Running™ shoe.Ideal for racing and training at any distance.Adjusting to Newton running shoes will depend upon several factors including: your current running shoes, your running form, gait efficiency, as well as your speed and flexibility. Those new to natural running form, or those transitioning from a shoe with traditional cushioning will benefit from spending adequate time adjusting. This is because your body will need time to lengthen the muscles and tendons on the back of the leg and under the foot.Newton recommends that first-timers walk in their shoes for several days to become accustomed to the level platform. Walking barefoot on safe and comfortable surfaces can also be helpful. Once ready, begin by introducing short runs of no longer than 15 minutes every other day. Gradually add 10-15 minutes as your feet and leg muscles begin to strengthen. If you experience soreness that persists for more than two days, reduce time in shoes immediately. Rest and ice the area until the soreness subsides, then slowly begin introducing time in shoes again.Breathable, seamless mesh upper.Asymmetrical lacing system.Welded support straps.High-rebound EVA.Action/Reaction responsive, trampoline-like midsole cushioning protects and loses less energy with each step.Biomechanical metatarsal sensor plate lets the foot sense the ground for a lighter, more efficient stride.Differential: 2 mmHigh-density rubber at mid-foot.Lightweight EVA heel.Imported. Measurements: Heel Height: 1 1?4 in Weight: 7 ozProduct measurements were taken using size 9, width B - Medium. Please note that measurements may vary by size.