Some workout/running advice?!

Some workout/running advice?

I love running, but i dont want to lose any weight i am just getting to were i want to be as far as weight goes. 5'9 150 lbs. Now also i want to stay and even get stronger, but i dont want a lot of muscle mass. I like being extremely strong for my size. I live in florida so no hills or mountains. Can i incorperate something into a run that will also help me gain more strength and endurance? climb trees or something lol. something without using weights. i just dont really like lifting weights but i love to push my body to the limits. wierd i know. any advice?

If you want to be stronger then you need more muscle. Doesn't mean you have to bulk up though - less weight (eg a weight you can comfortably do sets of 20 at) more repetitions (and faster - but still controlled) builds up your strength and stamina without bulk - without all that grunting and going red in the face too! Doesn't have to be gym weights you can use things on your run even litre bottle of water - I'm sure you can also get weights to strap to your wrists/ankles to run with too.