Because its considered "surgery" and if you put strain on yourself, you could very well cause excess bleeding and other problems. You have to give yourself time for your body to heal. Wisdom teeth extraction is like any other surgery, it takes time. I do believeif it were me, I would not lift anything over 20 pounds. One of our cats weighs almost 20lbs, so thats my limit! Why push it if you don't have too. I am also sure your dentist would write you a presc. for work informing you should not lift for a certain amount of time. My dentist would do this for me. Hope I've helped!