The same shake up is required in training. The basics stay the same, just as you go to work every day and eat every day. You should keep the big lifts, squats, deads, presses, etc as primary in your program. However, set aside a few minutes at the end of your workout to mix it up. Grab a plate and try to flip it and catch it, pick up some 35's and try to pinch grip them, or attempt an isometric hold on the glute ham raise. It doesn't really matter what it is, as long as it's different from your usual routine!
I'll give you some ideas by explaining a few shake ups we have attempted. At the end of a lower training day in July, we decided to attempt one handed tire flips. There isn't much of a standard or protocol on how to accomplish this, but we decided to give it a shot. At first, we couldn't get our hands underneath the tire, so we ended up rolling it into the yard and digging a small hole under one of the treads. It was just large enough for us to slide our hand under. After a few attempts people started landing the one handed flips. It was a great sense of accomplishment for those involved! They forgot about the strain of the dead lifts, GHRs and chain step-ups just a few minutes before. The next day, everyone had sore legs, hands and forearms primarily from the tire work.