This is a paper that emphasizes mindfulness especially in competition. This study took BMX athletes, and scanned their brains with an fMRI, before giving them a mindful performance enhancement, awareness and knowledge (mPEAK) intervention. Then they scanned their brains again after the intervention to find differences. The study found this program increased the regulation of psychological stress as well as an increased feeling of comfort in their bodies and being able to sense changes that could lead to this stress quicker.
Lori Haase, April C May, Maryam Falahpour, Sara Isakovic, Alan N Simmons, Steve Hickman, Tom Liu, & Martin P Paulus. (2015). A pilot study investigating changes in neural processing after mindfulness training in elite athletes. Frontiers in Behavioral Neuroscience, 9.