He is currently weighing 90 kgs for his next film Dangal where he plays a wrestler.
For this role he has gained 22 kilos from his last film PK where he weighed 68 kgs.
In Ghajini, Aamir had an extremely muscular body with 8 pack abs.
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While Aamir became extremely lean for 3 Idiots where he played a student.
Aamir has constantly been moulding his body as per his role for his films.