I'm pretty lean, and until recently had a very low body fat %. When I workout after being lazy for while my weight will usually drop, then I'll maintain for awhile, add 5-10lbs and the more maintaining. My question is how much does cardio really affect weight training? I love mountain biking and have had people tell me that if I want to put on weight I've gotta stop the heavy cardio. When I weight train I'll try to eat 2/3 of my body weight or more in grams of protien. I'm currently living on a lake and today ended with swimming across it and back with a neighbor. He said it was a 1/4 mile across, but I believe that is on the high side. We swam across, took a break while the other two that were with us caught up, then started again after they had a short break, Wasn't hard swimming by any means, bud cardio none the less. I'm going to try to go back to grilled chicken, salmon and sirloin for a high protein meal. Another question is how good or bad is peanut butter as a source of protien? I figure its a quick easy way to get in an extra 8-10 grams of protein throughout the day.