Stress can leave you tight. Challenging workouts can leave you tight. Long, hard runs can leave you tight. Heck, just sitting at your desk or driving for a long time can leave you tight! Since so many activities can leave your muscles tight, you need to give them a little extra TLC and stretch. But you don’t just want to stretch a cold muscle! Save these muscle-lengthening moves for when your body is warmed up, like after a walk, hike, bike ride, run, or these cardio moves you can do at home. We’ve organized them by body part so you can easily find the stretch your body needs.