We can appreciate that confidence is good and hesitation is bad, but how can we get ourselves in the proper frame of mind? This is where the use of visualization devices comes into play. This is simply any mental image or motivational thought that you can use to maximize your focus.
In the case of meditation, one hopes to clear the mind of active thought. Without thought of any kind, there can be no self doubt and, therefore, nothing between you and the task at hand. This is one approach.
Another is to actively think of something which positively motivates you to action. When in danger, your body reacts with the ‘fight or flight’ response to give you the extra adrenaline for increased strength and speed. Here, you focus on a thought to artificially create this response and momentarily afford you berzerker rage.
Exactly what you think of can be very personal. It can be anything that gets you riled up, or calmed down, depending on which state is most conducive to your performance. For instance, you can imagine you will win a million dollars for making the break, or that your house will be blown up if you fail. Use whatever it takes to motivate you to try as though your life depends on it.
If the break genuinely requires more than your full effort, then it is beyond your capability and no visualization technique can help you. There is nothing to do but train more and try again when you have sufficiently increased your power and conditioning. Have patience.