So I have been working out a little (jk I was just running a mile) and I noticed that every time I work out, I get red and it stays like that for a while! Why does that happen?

Investigator a has biological specimens that are coded and linked to identifiers of the source individuals. investigator a provides the specimens to investigator b but does not provide the individual identifiers. investigator b agrees not to re-identify the source individuals. is investigator b's research using the biospecimens human subjects research according to the definition of human subjects research in the federal regulations?