I weigh 14 stone but In my head I’m a 7-stone weakling

Showing unnerving insight, their director invited me to give a workshop on the subject to the young actors. I mention his apparent insight, as body dysmorphia is a condition from which, unbeknown to him, I suffer.

I am happy to admit I am gym obsessed and weight-lift at least five times a week, but it's not pure vanity. Behind it is insecurity about my appearance and a mismatch between my internal image of myself and actuality. On a bad day I see myself as a weak, skinny figure (a flashback to my teenage years) when the reality is, at 90kg (just over 14 stone), I can no longer fit into my favourite jackets.

Body image is a term that has come to mean our "mind's eye" image of our physical appearance, in contrast with the "outer" image as rated by an unbiased observer. Most would think these two correlate substantially, but studies have shown the overlap to be astonishingly low at five per cent. It's this body image that is closely related to psychological factors and clinical conditions like eating disorders, depression and low self-esteem.

My problem, muscle dysmorphia or bigorexia, appears to be a new form of body image disturbance in men that has received little investigation. The ideal male image in adverts and the press is one of a lean, muscular, fit man. As with women, it's the increase in these images and the pressures of sports that have been proposed as causes of male image disorders.

One of the few studies assessed the changes made to male action toys over a 30-year period. Such toys included GI Joe, Luke Skywalker and Han Solo, Iron Man, Batman and Wolverine.

Researchers measured the waist, chest and biceps of the figures and scaled the results up to the dimensions of an average-height male. They found huge increases in chest and bicep measurements over the 30 years, until, extrapolated to an average-height male, GI Joe's biceps would be larger than any bodybuilder in history.

While there is no evidence that exposure to male action figures leads boys to develop a negative body image, or pursue bodybuilding, if women have been so negatively influenced by imagery it's not such a stab in the dark to suggest that men might be too.

Conditions like anorexia and bigorexia are rare in developing countries which do not give their children action figures as toys or have the relentless flow of images of airbrushed perfection in their media.

So I look forward to the Youth Theatre's production and finding out the views of a younger generation that is being hardest hit by these issues.