A study in Canada says growing numbers of young people are becoming obsessed with their muscle size. This obsession is a mental health condition known as "bigorexia". Kara Becker, an eating disorder therapist, spoke to the HuffPost about the condition. She said: "Bigorexia is a psychological condition…which involves a distorted self-image that focuses specifically on muscle size and physical appearance." Sufferers can get very distressed over their lack of muscularity. Bigorexia can affect even those who work out regularly and have the physique of a bodybuilder.

Researchers said bigorexia was rising in teenagers and people in their twenties. A quarter of men and 10 per cent of women in their research could suffer from it. Ms Becker said many factors cause young people to worry about their body shape. She said: "People with low self-esteem, perfectionism, or obsessive-compulsive tendencies are more vulnerable." Social media may add to this problem. Youngsters can be flooded with images of people with the "perfect" body. Another cause may be the marketing of muscle-building supplements and anabolic steroids.