How has Moustafa Ismail increased his arms?

Moustafa Ismail, an Egyptian bodybuilder, has the largest arms in the world. He was recorded in the Guinness book of the world records. This person claims that his large biceps are natural. The bodybuilder says that he has the largest biceps in the world because he has very strict nutrition and workouts. He eats chickens, almonds and fish each day. The Egyptian bodybuilder also consumes much water and protein shakes.
However it is obvious that nutrition and trainings play great role, many people doubt about natural arms of Moustafa Ismail. It is difficult to believe that suitable workouts and diets can lead to such increase in arms. Which conditions are responsible for the large arms of the Egyptian bodybuilder?
When it was announced that Moustafa Ismail’s arms were 32 inches, accusations related to administration of steroids appeared soon. Several individuals suggest that steroids are responsible for the large arms of this person. What did the Egyptian bodybuilder claim about application administration of steroids? He affirmed that he had used steroids while living in Egypt. Purchase and application of these preparations are legal under laws of this country. These preparations are sold at any drug store in Egypt. Moreover, steroids are cheap there. But Moustafa Ismail noted that he had to stop administering these preparations, when he moved to the USA. It is know that purchase and administration of these drugs without a prescription are claimed to be criminal under laws of the US. These preparations are bought on the black market by those that apply them in the US illegally. Thus, Moustafa Ismail stopped taking these medications after he moved to the USA.
But if even the Egyptian bodybuilder uses anabolic steroids, it doesn’t matter because these products don’t enhance arms. They are not responsible for Moustafa Ismail’s large arms.
There are other remedies which can enhance arms. They are named “site enhancement oils” (SEO). Synthol is one of the most frequently used SEO. This preparation is applied by bodybuilders. It is administered in order to enhance muscles in circumference. Thus, it is supposed that the Egyptian bodybuilder takes Synthol. However, the Egyptian bodybuilder affirms that he doesn’t use this product.
The Egyptian bodybuilder affirms that he is hurt by accusations linked with anabolic steroids and Synthol. He has submitted to examination conducted by an independent doctor that hasn’t found  any abnormality in the arms of this guy. Thus, it is unclear whether the bodybuilder’s arms are natural or not.