India, Sept. 10 -- Losing weight feels like a big win, but what happens when the kilos creep back just as quickly? It's a frustrating cycle many people struggle with, no matter how disciplined they are. Celebrity fitness trainer Siddhartha Singh, who has trained stars like Tamannaah Bhatia, shares in his August 30 Instagram post a surprising reason why so many people lose weight but fail to maintain it, and shares what it really takes to keep the results long-term. (Also read: Fitness coach shares 'Japanese eating rule' Hara Hachi Bu to stay lean and shredded without ever dieting )

Siddhartha explains in his post, "You lost a lot of weight and then you gained it back. I'll tell you three reasons why this is happening again and again."

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