Describir: The effect of handle height and cart load on the initial hand forces in cart pushing and pulling /

           _    _                ___     __   _     _____             
    ___   | || | ||   ____      / _ \\  | || | ||  |  ___||     ___   
   /   || | || | ||  |    \\   | / \ || | '--' ||  | ||__      /   || 
  | [] || | \\_/ ||  | [] ||   | \_/ || | .--. ||  | ||__     | [] || 
   \__ ||  \____//   |  __//    \___//  |_|| |_||  |_____||    \__ || 
    -|_||   `---`    |_|`-`     `---`   `-`  `-`   `-----`      -|_|| 
     `-`             `-`                                         `-`  
 __   __  
 \ \\/ // 
  \ ` //  
   | ||   
   |_||   
   `-`'