I've been trying to do the same thing as you for about six months. It's been amazingly tough. Here's what I've learned so far. I personally cannot play tennis after lifting. I find that it throws my muscle control off so bad that it isn't worth playing at any point in the same day. As long as I lift after my playing/hitting sessions everything tends to be ok. The distance running is another story. I'm up to 5 miles every other day. The trick here is to not lift my legs or lower back on those running days. When I don't have a distance running day, then I do sprints. It's like a giant puzzle of activities that requires large amounts of planning in order to stabilize a routine. I've put on 7 lbs. of muscle over the last six months but with great sacrifices. Plus now after reading my post I feel like a huge looser, but what the hell. Later...