You may get sick if you cool down too quickly after exercise.

The claim that you may get sick if you cool down too quickly after exercise primarily refers to the physiological effects of abruptly stopping physical activity. The core factual assertion is that a sudden stop can cause adverse symptoms such as dizziness, lightheadedness, or fainting. Multiple reputable sources explain that during exercise, the heart rate is elevated and blood vessels are dilated to supply muscles with oxygen.

If exercise stops suddenly, blood pressure can drop while vessels remain dilated, leading to insufficient blood flow to the brain and resulting in feeling sick or fainting.nytimes.comnytimes.comThe Truth About Cooling Down After Exercisefocusphysiotherapy.comfocusphysiotherapy.comHow to cool down after a workouttempo.fittempo.fitWhy You Should Always Cool Down After a Workout This is a well-documented cardiovascular response rather than an illness per se. The term "get sick" in the claim is somewhat ambiguous; it does not mean contracting an infection but rather experiencing acute symptoms related to circulatory adjustments.

There is no credible evidence that cooling down too quickly causes infections or long-term illness. Instead, the risk is immediate transient symptoms due to rapid physiological changes.

Additionally, a gradual cool-down helps the body recover more effectively and reduces muscle soreness.heart.orgheart.orgWarm Up, Cool Down Therefore, while the claim is broadly accurate in warning about potential negative effects of stopping exercise abruptly, it should be understood in the context of circulatory and neurological symptoms rather than illness in the infectious or chronic sense.