Definition
Rest between sets dictates how much weight you can lift on the next set. Use 2–4 minutes for heavy compounds (strength and full hypertrophy), 60–90 seconds for isolation work, and 30–45 seconds for metabolic finishers. Cutting rest 'to make it harder' usually just means lifting less weight.
Real questions
Is longer rest better for muscle growth?
Generally yes — 2–3 minutes between hypertrophy sets allows full reps at full weight, which beats short rest plus reduced load.
Stack with
Put it to work
Coach Foster builds your program around rest period and the rest of the fundamentals, shaped to your body and your week.