Compound exercise

In a compound exercise two or more joints move: hips, knees and ankles in a squat, shoulders and elbows in a bench press. That's why the loads are big and one set works lots of muscle. In an isolation exercise one joint moves: a curl, a leg extension, a lateral raise.

On the site and in the diary I count as compound the exercises with a movement pattern: squat, hinge (the deadlift family), and presses and rows — horizontal and vertical. Those six movements are what any program is built on.

Compounds are the base of strength and save time, but isolation grows muscle too and covers what compounds don't load much: side delts, hamstrings in knee flexion. More in the compound vs isolation guide.