CHANDLER, JOE V. and STEVEN N. BLAIR. The effect of amphetamines on selected physiological components related to athletic success. Med. Sci. Sports Exercise, Vol. 12, No. 1, pp. 65–69, 1980. Six male college students were tested under two experimental conditions; amphetamine and no amphetamine. Each subject was tested three times under each condition. A double-blind placebo-controlled approach was employed and on six consecutive Fridays the subjects received either a placebo or 15 mg of Dexedrine per 70 kg of body weight 2 hours prior to testing. The physiological components tested were strength, muscular power, running speed, acceleration, aerobic power, and anaerobic capacity. Other variables evaluated were pre-exercise and maximum heart rates, respiratory exchange ratio and time to exhaustion. Data analysis revealed significant increases in knee extension strength, acceleration, anaerobic capacity, time to exhaustion, and pre-exercise and maximum heart rates. The most revealing results were in the area of increased time to exhaustion during the Vo2max test presumably due to higher lactic acid tolerance, thus a possible rationale to substantiate the theory that this drug has the ability to mask fatigue. It may also be possible that the biochemical actions of the drug alter fatigue processes directly. The results demonstrate that amphetamines have no effect on aerobic power, but further research will be necessary to clarify the drug's influence on muscular power-dominated movements.