Caffeine found in coffee leads to an increased production of adrenaline which stimulates energy production and improves blood flow to the muscles and the heart, says an expert.

According to John Stanley, lecturer in biochemistry, Trinity College, caffeine could modulate fatigue and influence ratings of exertion, perceived pain and energy levels, all of which are likely to lead to improvement in performance.

"The ability of caffeine in coffee to improve physical performance during aerobic exercise and to restore mental performance when it has been impaired by fatigue deserves wider recognition,” femalefirst.co.uk quoted Stanley as saying.

Drinking a cup of coffee about 20-30 minutes before you exercise can allow you to exercise for up to 30 percent longer. The most notable impact of caffeine on performance is in sports such as swimming, cycling and tennis.

Moderate coffee intake can also help improve alertness and concentration due to its caffeine content. 

Caffeine is well known for its stimulating effects which have proven benefits for mental performance. In fact, the European Food Safety Authority (EFSA) has concluded that there is sufficient evidence to support a cause and effect relationship for the effect of caffeine on alertness and attention.