Exercise and IUD/IUS

Hey so I just had the Mirena inserted, not feeling any worse than I usually do on my period but just wondered if there's any advice on when you can do vigorous exercise again. I know it's not going to come out easily but just wanted to see if anyone had any experience of running/weights at the gym pretty soon after having it inserted and did it feel alright? I am training for a triathlon and don't want it to cause any problems 😋