I am finally able to do 5 pull ups. As this puts me in the optimal rep range for strength gains I thought about adding weight to stay in that rep range.
I do my exercises at home, that's why I thought about loading a backpack with dumbbell plates. I really like the effect pull ups have on my core (I often had sore abs after a day of "greasing the grove"-style exercise). While weights in a backpack increase the resistance on my upper body, I fear that my core training is neglected.
Are my worries justified? How do different positions of weights (on the back, the chest, around the hip, on the feet) impact pull ups?