  Modern Running Shoes & Heel Striking , Daniel Lieberman, Harvard University. running shoes being characterized by a padded sole, stiff soles and arch support, and sloping down from a more padded heel to a less padded forefoot.
<coherence>   Modern Running Shoes & Heel Striking , Daniel Lieberman, Harvard University. running shoes being characterized by a padded sole, stiff soles and arch support, and sloping down from a more padded heel to a less padded forefoot.
 Modern Running Shoes & Heel Striking . Harvard University. running shoes being characterized by a padded sole, stiff soles and arch support, and sloping down from a more padded heel to a less padded forefoot.