Rapid Loading Nitric Oxide. Pre-Training Fuel. Prolab Quick Fire is a powerful pre-training formula that drives explosive training performance to push your workout to the next level. Its quick loading effects fire up a full range of both mind and muscle energy systems. Each dose helps launce Nitric Oxide fueled blood blow and supplies nutrients to fuel muscle contractions, feed prolonged endurance and heighten mental focus. Super-Charged Energy, Intensity & Focus. Promotes Muscle Pumping Vascularity. Fuels the Body to Train Longer & Harder.