India, Oct. 4 -- We often marvel at how actors look perfectly toned and fit, even with gruelling shoot schedules and long hours on set. Celebrity fitness trainer Vinod Channa, who has guided stars like Anant Ambani and Nita Ambani on their fitness journeys, breaks down the secret behind their on-screen physiques in his September 16 Instagram post. (Also read: Ranbir Kapoor's fitness trainer shares 5 reasons why many people fail to lose weight: 'The key is to keep challenging.' )

"Celebrities stay fit during film shoots because they work really hard, consistently, over the years," Channa explains. "This isn't something that happens in a day. They work out throughout the year, which is why they look so fit for a specific movie."

He adds, ...