The professional bodybuilder Rich Piana, who built an army of one million followers on Instagram, died on August 25 after spending two weeks in a coma. And while the world still waits to hear what killed the athlete, people are weighing in with their own opinions.

In an interview with UK paper the Daily Star, an expert in fitness and marital arts Matt Fiddes claims it was most likely insulin that killed Rich Piana. He believes Piana might not have eaten enough sugars to balance insulin he may have taken before a photo-shoot.

“If the photo-shoot dragged on a little bit he may not have eaten enough sugars to balance what insulin he would have taken? In my view, he took a pre workout substance, too much to create this pump and his heart’s gone crazy.

He’s effectively had a workout by getting a pump for the photoshoot and he’s on insulin so he’s not taken the right sugars. He’s got home, he’x exhausted and he just simply fell into a diabetic coma which is extremely common in athletes.”

Fiddes believes it would have also contained ECA, a pre-workout drug cocktail that may also have endangered his health:

“It will give a crazy rush of energy, an insane amount of power and it will make the workout 20 to 30 times more powerful.”

This is combined with caffeine and aspirin, which allows the blood to absorb the substances quickly and numbs workout pain.

As previously reported, His girlfriend Chanel Jansen spoke out after his death to slam critics who suggested steroids and class A drugs were behind his death. She denied he took illegal drugs and said he hadn’t been “overly juicing” before he died. Chantel was forced to deny a bag of white powder found at his home was cocaine.

Mystery still surrounds what exactly killed the 22-stone muscle man, who built up a huge fan-base across the world thanks to his intense workout regime.

See also: Rich Piana Tribute