Heidi is back with more fitness tips! I've attached a guide for proper posture when using the elliptical as well as a video for the squat walk that Heidi mentions. Now go get that supermodel body! 1. Stick your butt out on the elliptical machine. This shifts the focus to your butt, hamstrings, outer thighs, and quadriceps. (If you stand up too straight--a common mistake--you work only your quads.) 2. When you're doing any kind of athletic movement--jumping, lunging, lifting weights--never lock your elbows or knees. Keep them slightly "soft" (but not floppy) to prevent joint injury. 3.MUST-DO MOVE: Platypus walk TARGETS: Butt HOW TO DO IT: Firmly grasp a seven- to 10-pound medicine ball--or a dumbbell that weighs between four and 10 pounds--overhead with both hands (keeping arms straight). Squat as low as you can go, toes pointing out. Remaining in the squat, walk slowly forward for eight steps, then slowly backward for another eight. Repeat the sequence.