A punching bag is a sturdy bag designed to be repeatedly punched. A punching bag is usually cylindrical and filled with various materials of suitable hardness.
A mixed martial arts fighter "working his hands" on a heavy bag
An 1892 advertisement for The Lively Sparring Bag
Muhammad Ali training with a speed bag (or speedball)
A "body opponent bag" on a pedestal mount
A strike is a directed, forceful physical attack with either a part of the human body or with a handheld object, intended to cause blunt or penetrating trauma upon an opponent.
Senegalese Naval Infantry and US Marines practice striking.
Bas-relief of an elbow strike to the jaw at Angkor Wat (12th century) in Cambodia