Can you do serious weight lifting while taking warfarin/coumadin?

U can but? Warfarin is a blood thinner. If one is weight lifting and "seriously" doing this, one runs the risk of tearing muscles and having bleeding occur in that area of the body. This could be minimal or significant. I would recommend you discuss this thoroughly with your physician and with your trainer and with the health club where you work out. You are on serious medicine and i would take the conse.
Depends. Depends on what condition you are taking it for. Usually yes as long as you avoid serious trauma and don't drop the weights on yourself, and as long as weight lifting is not contraindicated with health condition for which you are taking coumadin (warfarin). Your best bet is to ask doctor who monitors your coumadin (warfarin).