The short answer: No. But it also depends on the style. Most forms of yoga involve "static stretching," or holds in poses/stretches that last 30 seconds or longer. Multiple studies show that static stretching prior to lifting negatively affects strength. The reasoning: static stretching temporarily decreases the muscle's elasticity and ability to recoil. Think of your muscles as being a bit like resistance bands -- everyone knows which bands in the gym are new and which ones are old simply based on how elastic they feel. An older band no longer maintains its original stretchy elasticity yet the new band has a snappy recoil and provides much greater resistance in its fully stretched position. Your static stretching turns your muscles into the aged resistance band -- too stretched to maintain a good recoil, and a decrease in recoil = a decrease in strength. That being said, a vinyasa-style "flow" may be a safer option due to its dynamic and constantly moving structure but it is still not a substitute for intentional mobilization and prehab drills.