Yeah could you please help me there... I never understood how one time is adequate. I was going to start a every other day fullbody routine, which means I'd hit my chest, delts, back, biceps, triceps etc. 3/4 times a week...
Not if you have worked them hard enough. They can take several days to heal.
Some people like to work them every 4 days as opposed to once a week. I think the general consensus is that is a minimum.
I personally saw greater strength and growth when I stopped hitiing muscle groups more than once a week. Of course, I also made sure I was tearing my muscles up on the day I worked them.
It is hard to take the needed time off. I just got back from a week off altogether. I hated it. I felt fat and small at the same time. Felt weak and lazy. But, still forced myself to take the time off, and I feel 110% better this week. Time off and away is needed. Even when it's just a week between hitting muscle groups.
Try it for a month or two. If you don't see any improvement, hit them twice a week. Keep trying different things until you find what works. But don't get frustrated when what you are doing isn't working, just try something new.