When doing downward dog, don't rest your weight on the heel area of your hands. Even at human weights, it puts strain on your wrists. This is the graphic that taught me what to do: https://s-media-cache-ak0.pinimg.com/736x/72/ed/64/72ed648c08b32c52e67ab85fef162959.jpg source: Do yoga frequently but not regularly, was having sore wrists, googled.