DXM is also used recreationally. When exceeding label-specified maximum dosages, dextromethorphan acts as a dissociative anesthetic. Its mechanism of action is via multiple effects, including actions as a nonselective serotonin reuptake inhibitor and a sigma-1 receptor agonist.
Aroldis Chapman has thrown the fastest pitch ever recorded, but he has challengers for baseball's hottest heater in 2017. Ever since Aroldis Chapman delivered a 105 mph fastball to Tony Gwynn Jr., Chapman's name has been synonymous with velocity.
The four-seam fastball is the most common variant of the fastball. The pitch is used often by the pitcher to get ahead in the count or when he needs to throw a strike. This type of fastball is intended to have minimal lateral movement, relying more on its velocity. It is often perceived as the fastest pitch a pitcher throws, with recorded top speeds above 100 mph. The fastest pitch recognized by MLB was on September 25, 2010, at Petco Park in San Diego by then Cincinnati Reds left-handed relief pitcher Aroldis Chapman. It was clocked at 105.1 miles per hour.