Celebrity Central / Top 25 Celebs
Credit: Isaac V./Broadimage
Published: Wednesday December 21, 2011 15:00 PM EST
More from PEOPLE
See More News
110 of 286
While others track intervals with a stopwatch, the model mom likes to count down with a $4,100 Cartier "Tank Francaise" sterling silver timepiece.
Copyright © 2014 Time Inc. All rights reserved. Reproduction in whole or in part without permission is prohibited.
In partnership with AOL