Cynthia Erivo wore her fitness watch underneath her Elphaba costume on the set of 'Wicked' to ensure she got her daily steps in.The 37-year-old actress plays the Wicked Witch of the West alongside Ariana Grande's Glinda The Good Witch in the two-part big-screen adaptation of the Broadway classic and the self-professed "fitness freak" admits nothing was going to stop her achieving her daily step count whilst filming the fantasy film.Speaking on 'Wtf With Marc Maron', she was asked if she had her Fitbit on underneath her witch ensemble and she replied: "Yes."Asked if she checked it, she said: "I did. I am not even joking. I am being so serious."I had it on me all day. I can either put it in my boot by my ankle, because that is where my pulse is, or I put it on my hip.