Supplements to Keep Muscle??

Right now I am taking Nitro-Tech and will probably keep taking b/c I like what I see so far. My question is. In about a month I am going to start taking xenadrine to try and get more muscle definition. I am going to be working about 5 days a week and doing cardio 2 days a week and running stadiums 2 days a week accompanied by sprints. Should I take something else along with Nitro-Tech and Xenadrine so that I do not loose muscle, are as long as I take in a good amount of protein and eat right I should keep muscle??
Any suggestions will help..Thanks

lots of protein low carbs, low calories,

get some Glutamine too

Thats what I was wondering about....Is there any certain kind to get, or is it all the same??

This should help

http://www.anabolicreview.com//vbull...mine+Confusion


there a couple threads on glutamine and glutamine peptides
and whats better