Myself and collaborators Donald Reid, Stefano Marras, and Paolo Domenici just published a new paper in Frontiers in Physiology, showing that individual fish that respond soonest to a simulated predator attack also take the longest to recover after exercise. This is important because prey fish will often use intense bursts of exercise to escape predators and their normal behaviour could be compromised during the recovery from this activity. This work was done using juvenile mullet:

Why do these faster responding fish take longer to recover? It seems that, after being startled, these particular fish spend more energy on being vigilant (perhaps looking out for another attack), and that this extra energy expenditure reduces resources available to fuel recovery. 

This work was done at the Institute for the Coastal Marine Environment in beautiful Oristano, Sardinia, Italy, with funds from COST Action  FA1004 Conservation Physiology of Marine Fishes.