Now, there will come a time when you wrestle with the thought of skipping leg day. You're only human. But you mustn't. You need to stay strong.Leg days are so important. Why? Well, we’re glad you asked. You might not believe it, but your legs and core produce the majority of your power during heaving lifting. Yes, even when you’re bench-pressing, it is your lower body that is engaged to help provide a stable platform to pump from. If you lack conditioning, your big lifts will only get so far.