Lou Ferrigno was training Michael Jackson to get in shape for his upcoming 50-concert stint in London, and the former "The Incredible Hulk" star and body builder tells ET that he was shocked to hear the news of the pop star's death, given his knowledge of Jackson's physical condition.

"It was a shock to me because when I was with him he was in the best shape of his life," Ferrigno tells ET's Thea Andrews.

Ferrigno and Jackson had developed a special bond and friendship over the last 15 years, which was when Ferrigno had started training him for a concert tour. As for any indication of a heart condition, Ferrigno says, "There was no discussion about medication, about medical problems; the guy seemed like he was great. Michael looked just as good as I saw him 15 years ago; he was strong."

As for Jackson's reported weight loss, Ferrigno says, "I think because there was so much stress, and he was seeing a voice teacher, he was seeing me, and then he was rehearsing downtown -- he was doing, like, seven to eight things a day, so I think that contributed to his weight loss."

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