When Ronaldo was 15 years old, he was diagnosed with tachycardia – a racing heart condition, which meant his heart rate was higher than normal even while resting. The condition might have forced him to give up playing football but fortunately, it was diagnosed and treated before it became a serious problem. He had an operation in which a laser was used to cauterize the area of his heart that was causing the problem. The surgery took place and he was released the same day. Ronaldo was back in training just a few days later.