Since she has signed up for two action movies (Avengers Assemble and Luc Besson film Lucy), Scarlett Johansson needs to stay in shape and she does it by training martial arts and having a special diet.
A source told OK! magazine: ”Scarlett really got into martial arts. She has also logged a lot of time toning her muscles in the gym. She likes to mix up her workouts with circuits and resistance training.” As for her diet, the insider said: ”She’s a grazer. She will have between six and eight small meals a day.”