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.
There is a strong belief that throwing a baseball repeatedly at high rates of speed can help lead to arm injuries, yet the average velocity of pitches in baseball keeps rising every year. In 2008, the average four-seam fastball in Major League Baseball was 90.9 miles per hour, according to data on Fangraphs.com.