extra notes on lever/pulley system
class two mechanical advantage, wheelbarrow, calf raise
class one neck flexion/extension
class three bicep flexion
most muscles in the body are class three
concentric and eccentric movements will turn a class 3 to a class 2 and vice versa
however many pulleys you divide that by to determine how much force Ex. 2 pulleys you need ½ the force, 4 pulleys you need ¼ the force (a two pulley system lifting a 100lbs weight needs 50lbs force, but if it where 4 pulleys it would only need 25lbs of force)
you need double the distance ex. in a two pulley system, if you pull the rope 10 feet, the load will only move 5 feet, demonstrating the principle that while the input force is reduced, the input distance is increased.