When I started working out seriously a few months ago, I couldn't do three push ups without pulling something—in fact, the first two times my trainer had me do modified (girl) push-ups, I pulled muscles in separate areas both times. Not fun.
After recuperating from those minor injuries, we kept at the push-ups, but in creative ways: push-ups with one hand on a medicine ball, then rolling it to the other hand; push-ups on risers, moving hands on and off the riser while in plank position, then lowering; push-ups on benches, yada, yada, yada. Along the way, I've made some strides in the push up department. And it has had a very positive impact on my Chaturanga Dandasanas.
Weight-Lifting and Yoga: Yin and Yang
While the hand placement for traditional push-ups and Chaturangas are different, the need for upper body and abdominal strength is common to both. Although many forms of yoga provide a serious workout, I firmly believe that weight-lifting has enabled me to fast-forward through months or even years of building upper body strength through yoga alone—I'm able to hold plank pretty well, and lower in Chaturanga with integrity. Knowing how challenging push-ups were for me just a few months ago, if I hadn't been hitting the gym and gradually increasing the amoung of weight I lift, I seriously doubt I'd be where I am in my practice today. And push-ups are just one aspect that has translated beautifully—all the weighted lunges and wall sits my trainer has me do have also helped me develop key leg muscles I need to go deep in Warrior stances and lunges, and hold them.
Alternating between lifting and yoga—weights Monday, Wednesday, Friday and yoga Tuesday, Thursday, and Saturday—helps me feel extraordinarily balanced. Plus, the cardio I also do virtually everyday has been helpful in giving me the stamina I need to make it through 90-minute and two-hour Power Vinyasa classes that take you to the brink in terms of muscle fatigue, cardio, balance, and focus. I know some hardcore yogis are not a fan of lifting because it shortens the muscles, and fatigues them (definitely not good to lift and do "power" yoga the same day). But I think they really go well together and help tone and sculpt the body in a very pleasant way.