For military snipers, a muscle spasm at the wrong time could prove to be a problem. In a combat situation, the typical sniper would be in a concealed position prior to firing. However, the slightest miscalculation could result in a miss, revealing the sniper's location and forcing him to abandon his position to await another opportunity. Since the rifle's tripod, generally used by police snipers to keep their rifles steady to avoid a miss, may not be usable in a combat environment, military snipers are sometimes supplied with muscle relaxants or tranquilizers to help keep the arms steady while aiming and firing. This is meant to supplement the intensive training regimen of snipers, who need to be able to take precise aim, as well as keep their bodies as steady as possible when the rifle's recoil kicks in.
Police snipers, given the nature of the urban environment, have less of a need for muscle relaxants, though knee pain and lower back pain may prove to be issues when forced to snipe from unusual positions. The tight confines and corridors of an urban environment can occasionally make police sniper's jobs insanely difficult on a physical level, though typical police procedure is to put the sniper on level surface with a overview of the situation area which allows for a clear shot of the target. There is also a level of stress and anxiety associated with police sniping, as they are typically employed in highly sensitive hostage situations. Clearly, there has to be a degree of anxiety associated with the chances of missing a shot, and hitting a hostage in the process instead of the designated target.
Surgeons also require pinpoint precision, with even the slightest twitch in their arms would have potentially disastrous consequences on the patient's body. While surgeons who take muscle relaxants are not all that common, some have found that type of medication to be useful preparation before a surgery. This is particularly true when the surgery is deeply invasive, with the slightest error in the use of the scalpel usually within range to cut some of the body's major internal organs. While this is an assumed risk when performing a surgery, most doctors would prefer to take muscle relaxants to avoid an untimely muscle spasm rather than make a gross error and face a malpractice suit when he accidentally cuts a patient's right lung while operating on the heart.
Certain sports, notably basketball and baseball, also require a high degree of precision. While anabolic steroids and performance enhancers are often associated with scandals about doping in sports, some athletes are said to use muscle relaxants to help improve the precision of their movements. Due to the constant physical exertion and muscle stress that these athletes endure, it may not be entirely unusual for a few of these athletes to use pain killers as well.