Product Details "Experience a softer feel underfoot with the GEL-CUMULUS 25 shoe. These materials help create softer landings and a more energized toe-off during your training." Pronation Pronation is part of the natural movement of the human body and refers to the way your foot rolls inward for impact distribution upon landing. Understanding your pronation type can help you find a comfortable running shoe. The GEL-NIMBUS 25 is made for Underpronation and Neutral. Under Neutral Over Neutral Foot Type Normal size arches Push Off There is even distribution from the front of the foot. How your foot contacts the ground The foot lands on outside of the heel, then rolls inward (pronates) to absorb shock and support body weight. Under Foot Type High arches Push Off The pressure is on smaller toes on outside of How your foot contacts the ground The outer side of the heel hits the ground at an increased angle with little or no normal pronation, causing a large transmission of shock through the lower leg.