You can and you will!
The mind is very powerful and can control what we can and can't do. It is very common to have a mental barrier when lifting heavy or jumping on a high box or hitting that wall in a high intensity workout.
Is it possible to develop strategies to break your mental barrier? Absolutely. There are a couple of ways you can control this;
One more rep.
When that voice inside your head is screaming at you to “put down the barbell” or “get off the bar,” you fight back with one more rep. Completing just one more rep when everything inside of you is telling you to stop is a sure way to grow your mental muscles, and the next time you might do two more reps. Over time, this builds and you begin to control that voice.
When you are in the middle of a workout, you always should have small goals in your head. Small goals add up to big goals. For example, if your workout calls for 30 heavy thrusters, your first goal might just be to get to 5 thrusters. When you get to 5 and still feel good, you start thinking, “good, I’ll do 5 more without rest,” and when you get to 10 and start to feel fatigued I might just talk myself into “two more.” But at 12, you might use the “one more rep,” and then do it again. After a few “one more rep” goals, I am at 16 or 20 . . . and all of a sudden you might be close enough to 30 to either take a quick break and knock out the rest in one set, or even finish it off by chipping away on more rep at a time.
Break through that wall.
Some coaches can shout at you when they see you struggle; “Break through that wall, it’s the only way to get strong.” As soon as you hear your coach use this words you know you need to hit that wall and do that one more rep. Often the walls are easier to break then you might realise, you just need to try.
Your body can handle more than your mind thinks it can. Don’t let that little boss in your head beat you; go out there and show it that you are the boss!