Originally Posted by
Michael Wolf
20 minutes is a long rest period, to be sure. But if you didn't cool down too much, and it allowed you recovery enough to make the lifts, then it's ok.
But if it wasn't just a one time thing and you consistently need 20 minutes between sets to recover, and are still adding 5 lbs (or 2.5 kgs) squatting 3x5 three days every week, it's probably time to move to twice per week. So if you're squatting Monday, Wednesday, and Friday now you will add the weight Monday and Friday, and do a lighter squat workout Wednesday. Work up to 2 sets of 5 at about 80% of what you did on Monday.