What do Madonna, Dara Torres and Michelle Obama have in common? Aside from being achievers in their respective field, they are physically fit as can be seen from their beautiful well-toned bodies and muscular arms. Dara and Michelle O are both in their 40's while Madge is turning 52. Yet, look at these hot mommas. They can put some younger women to shame with their well-defined muscles in those toned and lean bodies. I wonder what their secret muscle builder is.