Out of curiosity - does anyone have a rough idea how many calories they burn doing BJJ. Our gym normally do a 30 - 45 minute sparring session and I find it really hard to judge how much I am actually burning. Sometimes I feel absolutely exhausted but I don't know if that is down to the lack of air in our gym and then some nights I feel like I have just had a light run. I suppose it all depends on your opponent and how hard they are working you. I'm trying to cut some weight but have found I've lost about as much as I can just from BJJ. I think since the 1st day I've trained I've lost about 10 - 14 lbs but I don't see my weight going down any lower. Probably have to start ditching the burgers and booze . Thanks in advance.