What is a potential side effect of taking diet pills prior to an exercise session?

Stimulant-based diet pills increase central nervous system arousal and sympathomimetic activity, producing increased alertness and elevated cardiovascular response - the opposite of fatigue.

Delayed-onset muscle soreness results from mechanical microtrauma to muscle fibers during eccentric loading, not from the pharmacological stimulant effects of diet pills.

Stimulant-containing diet pills have well-documented cardiovascular effects that measurably alter exercise hemodynamic responses, making the claim of no side effect factually incorrect.

Most diet pills contain stimulant compounds such as caffeine, sympathomimetic amines, or ephedrine-like substances that activate the sympathetic nervous system via adrenergic receptor stimulation. This produces chronotropic effects that raise heart rate and vasoconstrictive and inotropic effects that elevate blood pressure, compounding the normal cardiovascular demands of exercise and creating potential safety risks.