“CEP should always be worn next to skin,” Furgerson said. “We size using circumferential measurement, so wearing CEP socks or sleeves over the tights doesn’t really work. We want to make sure we are applying the right level of compression to the body, not the body and a pair of tights.
“If the tights are compression tights, we do not recommend wearing two compression garments that have an equal level of pressure. This could cause a doubling of compression in overlapping areas.“If they are standard running tights that make no specific claim on compression, they probably aren’t tight enough to cause a problem. That being the case, we still recommend wearing them under your tights. Golden rule: next to skin.”
Tip: On colder runs, compression socks under tights provide a second layer of warmth. Just make sure those tights aren’t compressing at any point below the knee.