Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
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PMID:The effect of amphetamines on selected physiological components related to athletic success. 739 5

Six men and 3 women on each of 4 days received 10 mg of methylphenidate or placebo (2 times a day) at 0800 and 1200 after 8 hr or 0 hr of sleep. Sleep latency was measured by the Multiple Sleep Latency Test (MSLT) at 0930, 1130, 1330, 1530, and 1730. Participants also completed divided-attention and auditory vigilance tasks at 1000 and 1400 and the Profile of Mood States (POMS) and the Addiction Research Center Inventory (ARCI) after the 0930 and 1330 latency tests. The drug increased mean latency on the MSLT in both sleep conditions. Performance only showed drug effects after prior sleep deprivation. On the POMS, the drug increased Vigor and reduced Fatigue and Depression scale scores, primarily after sleep deprivation. The drug increased the ARCI Amphetamine and Morphine-Benzedrine scores only in the basal state. The ARCI Pentobarbital score was increased by sleep deprivation and decreased by the drug.
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PMID:Alerting effects of methylphenidate under basal and sleep-deprived conditions. 938 61

A promising countermeasure for fatigue in sustained aviation operations is stimulant administration. However, well-controlled, aviation-relevant studies of the efficacy of medications such as Dexedrine are virtually nonexistent. In this investigation, flight performance, mood, and alertness were evaluated in 10 UH-60 pilots during sleep deprivation periods under Dexedrine or placebo. Relative to placebo, Dexedrine improved flight performance during straight-and-levels, climbs, descents, right turns, and a left-descending turn, with tendencies toward better performance during the left turns and the instrument landing system approach. Dexedrine markedly reduced subjective feelings of fatigue, confusion, and depression while increasing feelings of vigor. Central nervous system arousal was enhanced by Dexedrine relative to placebo. No significant side effects occurred, although Dexedrine was associated with mild asymptomatic increases in heart rate and BP. Thus, Dexedrine appears effective for the short-term sustainment of aviator performance during sustained operations. However, future work should investigate the efficacy of stimulants for longer-term use (e.g., more than 40 h of continuous wakefulness).
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PMID:An in-flight investigation of the efficacy of dextroamphetamine for sustaining helicopter pilot performance. 940 55