I'd never train back after legs (squats!). I do however train shoulders on leg day, after I get done with the legs. I only do 4 sets for my shoulders which is enough for me.
Heh, I do fullbody stuff not to failure. Even I find that I simply must do legs first as it incorporates the most muscle groups and takes the most effort.
A couple days ago I maxed out for 5 reps on squats and then SL Deads in immediate succession and was okay to go on with the rest of my workout. The trick is not to get crazy with your volume and you'll be fine.
Three sets is fine; you won't be burned out if you do multiple muscle groups.
It's interesting... because if I did front squats one day... I'm not sure how my zerchers would be the next... and so on...
but like someone said... if I did leg extensions, curls, etc... I could probably handle it... but I wouldn't expect my legs to grow a whole lot... not from the WORKOUT... but from the exercises.
I do it, and my "little baby exercises" are Rows, Power Cleans, and more. I have not seen too many little or even big babies handle the near mid-300s I'm using for PCs. I generally save PCs for another phase of training, but I've done this with no problems in the past. I tend to just do SLDLs, Rows, and calf work after my Squats, now. Three exercises. Squats beat me up, too, but it can be done.
try doing squats and doing another body part other than calves on top. you basically burn out your cns by doing squats. I know I just got done throwing up after squats, you gonna tell me to do back afterwards
As said, done. For that matter, done thrice weekly. You overtax your CNS if you go to failure too often or -say- push one's self to vomiting. Vomiting is not among the mechanisms necessary for strength increases or hypertrophy.