Which chemical is released by exercise?

• A. Dopamine
• B. Serotonin
• C. Endorphins
• D. Norepinephrine

Answer: (B)

Exercise triggers the release of several brain chemicals that influence mood, energy, and pain. Serotonin rises with physical activity, helping to elevate mood, promote a sense of well-being, and regulate sleep and appetite after a workout. This serotonergic boost contributes to the mood-enhancing effects many people notice with regular exercise. While other chemistries like endorphins also play a role in pain reduction and expression of the exercise experience, and norepinephrine and dopamine increase arousal and motivation, serotonin’s involvement in mood regulation makes it the best-supported answer for what is released by exercise in this context.