Sylvester Stallone has warned that being too fit can be bad for your health.
The 69-year-old actor has had to be in top shape for his various action film roles from the 80s onwards but when he has reduced his body fat too drastically to look as ripped as possible on screen it has made him ill.
The first time he felt the effects of over-training was when he transformed his body shape to play boxer Rocky Balboa in 'Rocky III'.
In an interview with Deadline, he said: "With the third one, which dealt with Rocky losing of the 'Eye of the Tiger' ... it took about a year to get into that shape. I wouldn't recommend it because maintaining that for so long actually can do physical harm to the kidneys. It causes anxiety because you're not getting enough nutrients. You are actually depleting yourself. The look was required for that movie, and that's when the action film thing took off."
Although the incredible physique he achieved for the sequel earned him a string of top action roles in movies such as 'First Blood', 'Cobra' and 'Demolition Man', by the mid-90s Stallone developed an "erratic heartbeat" due to his fitness regime.
The Hollywood icon - who is married to Jennifer Flavin, with whom he has three daughters; Sophia, Sistene and Scarlet - then decided to take on a role in 1997's 'Cop Land' which meant he could let the regime slip and gain some weight in order to correct the medical condition.
He said: "I got into this physical acting, and then it became ingrained in me, a lifestyle. Constantly working out and increasing your goals, physically, so you can do 'Cliffhanger' and 'Demolition Man'.
"Right before 'Cop Land' I had pushed a little too far and had an erratic heartbeat. So I said, maybe I should do a film that I can have pancakes every morning and not stay on a treadmill for hours a day. That was 'Cop Land'. I had such a great time."