I've never had problems with this before, but after taking 4 months off from rock climbing because of my knee/work, I'm having problems with my grip. I was trying to do shrugs with 120's, and around rep 8, they just dropped. I was perplexed, because i used to have no problems ever.. i could hang from a bar for like 10 mins easy. Anyway, i've never done any grip training before besides rock climbing, so i'm at a loss for what to do. Can anyone help?