Agonist: any primary moving muscle or group of muscles
(Bench press - ant. deltoid chest/ Deadlift - Glutes and quads)
Antagonist: any eccentrically charged or stretching muscle
( Bench Press - lower traps, rhomboid/ Deadlift - Hamstrings)
Synergist: any mucle or group of muscles stabilizing or assisting primary and joints)
(Bench press - lat. deltoids triceps forearms/ Deadlift - "core area" erector spinae adductors)