What does radiation mean?

A radiation is a emission of energy as electromagnetic waves or as moving subatomic particles, , especially high-energy particles that cause ionization

Ra·di·a·tion
ˌrādēˈāSH(ə)n/
noun
1.
PHYSICS
the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization.
the energy transmitted by radiation, as heat, light, electricity, etc.
plural noun: radiations
2.
BIOLOGY
divergence out from a central point, in particular evolution from an ancestral animal or plant group into a variety of new forms.

It’s a because it says during exercise so they are doing a athletic activity

You should try to limit foods that are high in carbs and trans fats