I do believe in willpower, determination and perseverance. Athletes who are mentally strong achieve that because they work to strengthen their willpower muscles with consistent steady effort. They use failures as stepping-stones to success. They will take risks but above that, they are consistent and steady in their approach. All the best athletes that I have been around have those qualities. I don't believe you can teach mental toughness by doing mindless workouts that make the athletes tired. The willpower and determination that builds mental strength comes from consistent mindful effort day in and day out, exercise-to-exercise, set-to-set throughout the workout each day. There are no magic workouts to develop this. It is a mindset; it is a willingness to put yourself in positions that test your concentration, your determination and your ability to execute in stressful situations. You are what you train to be, if you go through the motions and just do the work you are not building the mental strength necessary to excel in the competitive cauldron. Bring your mind to the workout, be fully engaged and build mental strength to parallel the physical strength, speed and endurance necessary to give yourself a chance to succeed.
Eat for growth, train for strength, live for the MOMENT.