[Jarod Connell graduated from NC State University with a degree in Human Biology and a minor in Sports Science. He is certified as a NASM-CPT and is taking part in the Athletic Lab Coaching Mentorship program.] Caffeine has long been used as an ergogenic aid in sports. How much do we really know about it or how much it helps us? Caffeine has been used in sports since the early 1900s due to its perceived ability to stimulate muscle and overcome mental fatigue (17). However, it wasn’t until the 1940s that notable research began to appear (17). In this blog, we’ll explore what caffeine does within our bodies and how it impacts sports performance. What does caffeine do in our body? Caffeine is shown to inhibit adenosine receptors and mostly targets the A1 and A2 adenosine receptors. This leads to increases in pain suppression, firing rates of motor units, and neurotransmitter release (1). Adenosine is shown to decrease some Central Nervous System (CNS) neurotransmitters, including dopamine, serotonin, acetylcholine, glutamate, and norepinephrine. This means adenosine slows down our neural activity and makes us sleepy (22). Because caffeine’s chemical structure resembles adenosine it inhibits adenosine from binding and binds to the receptors itself, increasing the concentration of these neurotransmitters, and thereby actually increasing neural activity and alertness (1). Caffeine was previously believed to increase lipolysis, the breakdown of fats for energy, saving our muscle glycogen from being used, and release of calcium from our intracellular stores. However, a study in 2010 by Davis and Green reported that a standard dose of caffeine doesn’t indicate that these mechanisms play a large role (14). This lines up with what was found in the Institute of Medicine article which reports [...]