One of the best ways you can train your grip strength to tackle the obstacles at an UltraBeast involves pull-up training. Time and time again people are forced to do 30 agonizing burpees on an obstacle that should otherwise be a piece of cake (and done in 10-15 seconds) if they only had the grip strength. Doorway pull-up bars are an inexpensive and easy way to train, especially when you wrap two towels around the bar and grip the towels as you exercise. Fortunately, the cost of owning one of these bad boys has gone down by 38%. Amazon is having a special on one of the high-quality ones!