Spray slow cooker with cooking spray. Place sweet potatoes, celery, onions, and mushrooms in the bottom of the slow cooker.
Season the chuck roast with salt and pepper. Heat olive oil in a pan over medium heat. Brown roast on all sides, about 30 seconds per side. Place on top of the veggies.
Mix together beef broth, rosemary, and Worcestershire in a small bowl. Pour the mixture over the top of the beef and veggies.
Cook on low for 10 hours.
Remove the lid and shred beef and mix well. Serve immediately and enjoy!