Factor V Leiden and physical activity

Dear Ask The Doctor: I am a 20 year old male and first experienced a blood clot at the age of 17, 3 years ago, I was in the hospital and was administered a PIC line into my right arm. And through that PIC line I acquired a large blood clot in my right arm. My father had recently had an incident with blood clots in his legs requiring him to be tested for Factor V Leiden, and was positive. So in turn they tested me after the incident and confirmed that I as well was positive for Factor V Leiden. I was put on blood thinners for 6months and with everything clearing up taken off of the medication. Ever since I have not had any blood clots. Before the incident which landed me in the hospital I was an active young teen, football, basketball, etc. Ever since my whole family has been living in fear and my active life style is long since gone. I have gained almost 30 pounds since then through various medications and inactivity. Recently in college I have picked up on the sport of jiu jitsu, I have been exercising with many jiu jitsu fighters and wanting to get into the sport. Through the sort time of me exercising I have felt a drastic change in my previous condition and physical stamina. Once my parents heard of my activities they put a stop to it. They are fearful that I will acquire another blood clot through the grappling that we are doing. I really don't want to stop this activity because of the fact of the drastic change it has made. I was wanting to know am in any danger continuing exercising with these jiu jitsu fighters.

Dear Christopher: If you have currently stopped all blood thinners and medications, I see no reason why you cannot partake in any sporting activities. The presence of a genetic variant such as Factor V Leiden alone is often insufficient to produce venous thromboembolism, but combined with a transient, acquired risk factor, the mutation becomes a pathologic substrate. Acquired risk factors may include age, obesity, oral contraceptives, hormone replacement therapy, smoking, and immobility. Therefore I think you would be more at risk of thromboembolism if inactive or obese. I recommend discussing this with your haematologist for further advice.