Q: I do yoga twice a week. Can I skip my weight training routines?
A: No! Don't let all those toned bodies in the studio fool you. "Yoga increases flexibility and strength, but it doesn't replace resistance training," says Leigh Crews, a trainer and yoga instructor in Rome, Ga. To continue to build muscle and increase bone density you need to progressively use more weight, upping your weight training program whenever your muscles get used to the workload. You can't do that with yoga, unless you're using free weights during your asanas (which isn't safe if you're barefoot!). While you can continually try more challenging yoga poses -- like handstands -- most yogis lead you through a set series of moves that you'll eventually master. Plus, the point of many yoga classes is not to build muscle, but to calm and focus the mind.
The good news is you don't have to choose between yoga poses and a weight training program.
Just add some iron to your schedule. Twice a week, on nonconsecutive days, do a total-body strength workout. Include at least one exercise for every major muscle group -- biceps, triceps, shoulders, back, chest, abs, butt and legs -- and do 2 or 3 sets of 8-12 reps of each move. You'll be ready to tackle heavier weights (and even tougher poses) in four to six weeks. Not only will strength training stave off osteoporosis and keep your metabolism revved, it helps you look slimmer too. For the best results, be sure to integrate weights into your routine.