What are some generalizations about caffeine’s effect on performance? What effect might caffeine have during pregnancy? Describe caffeine withdrawal.

Caffeine is known to improve and enhance performance, as it reduces fatigue and anxiety and even has a positive effect on basic cognitive functions. Consuming high doses of caffeine, however, can actually have a negative effect on both exercise and cognitive performance.

Expert Answers

An illustration of the letter 'A' in a speech bubbles

Generally, caffeine, as a stimulating drug, has several positive and beneficial effects on the body, as well as some negative effects; once consumed, caffeine affects the central and peripheral nervous systems, enhancing the activity of dopamine (the "feel good" hormone and neurotransmitter), which reduces stress, anxiety, and fatigue, improves concentration and focus, and increases alertness, motivation, and cognitive and emotional response; according to some studies, caffeine can even increase muscular strength and endurance, as well as speed. Thus, it is often taken by athletes as a safe performance enhancer.

It is notable to mention, however, that caffeine is most effective when taken in moderate doses, as consumption of higher dosages (more than 400 or 600 mg of caffeine a day) can actually increase anxiety and nervousness and may result in abnormal heart rate, increased blood pressure, gastrointestinal problems, headaches, dehydration, and insomnia. Caffeine is not known to cause addiction as some other stimulating drugs do; however, some people may develop a tolerance to its effects; the brain and the body might also become so used to caffeine that not consuming it may cause headaches and nausea.

It takes ten hours for caffeine to completely leave the body. Those who consume it regularly and then abruptly stop may experience caffeine withdrawal, which lasts from two to nine days and is accompanied by symptoms commonly associated with the flu, such as: headache, nausea and vomiting, fatigue, drowsiness, and even muscle pain; it can also cause nervousness, irritability, sleep irregularities, and mood fluctuations.

Last Updated by eNotes Editorial on

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial