Marathon/Upper body strenght

Question
Hi, I am a 17 year old looking into running a marathon late this summer.  Over the past few years I have enjoyed running recreationally in the summers, but have never competed in a race over 5 miles long.  I only run during the summer, but weight lift year round.  I had my first run of the year last week, and went 6 miles.  It felt good, so now I'm considering a marathon.  I have good endurance, so I know I could do it (with plenty of training).  Here's my main concern: I'm naturally skinny, but I have gained some upper body strength (I weigh 167 lbs).  I'm worried that if I do train for a marathon, I will lose a lot of weight and all my upper body strength, then have to start over from zero when I am able to focus on lifting after the marathon.  Would it be possible to not lose too much weight during the 4 months I would train for the marathon, or would I need to devote myself almost exclusively to running?
Thanks for your help,
Mac

Answer
Hi Mac
If your focus is just to finish the marathon with out any major time goals i see no reason why you can't maintain your present situation.The key to make this happen will be your ability to manage your diet with the appropriate balance of carbs,proteins,and good fats along with the vegies in direct relation to the increase in your mileage.The other thing that will be a key is the deciding on how much recovery time between workouts you program into your schedule so as not to break down musculature,but to increase and maintain tissue.The one phrase you have to learn and practice and implement is WITHOUT REST AND RECOVERY THERE IS NO GROWTH.Rest in a training model can be active rest at very low level of running or some cross training or just take a day off etc.That is for you to decide based on how your feeling.It will be a balancing act, but you can make it happen if you know what your doing and can properly implement the proper macro nutrients and sort out the necessary recovery to enhance and maintain your present situation.Any other questions just get in touch Mac.

All the very best

John