I find myself always asking clients if they stretch knowing what the answer generally is. No. There are so many stretches that can prevent injuries, but...
Here are three stretches you can do anytime:
Hip flexors. Lower yourself onto one knee, as if you're going to propose. Lean slightly forward onto the front leg as you tighten your stomach and buttock muscles and tuck your hips under. You should feel the stretch along the top of the thigh in back. Switch legs and repeat.
Chest muscles (pectorals). Stand in a doorway with one arm up, your elbow at shoulder height and your hand at head height. Rest your forearm on the door frame and rotate away from the door. You'll feel a stretch across your chest and shoulder. Switch arms.
Back (latissimus dorsi). Kneel in front of a chair. Extend your arms to the sides of the chair and pull back gently without moving your arms. You'll feel the stretch across your back.