Will half marathons make my muscles small?

[Combray]

I presently run (40 minutes) and lift weights (30 minutes) on alternate days. I'd like to train for a couple of half marathons that are coming up. I'm just wondering if that's the wrong thing to do if I want to maintain my muscle mass. I'm an endomorph (stocky), so I wouldn't mind decreasing my body fat percentage, but I also want to maintain my muscle mass which is pretty decent. What advice can you give me?

 

[Habib]

I presently run (40 minutes) and lift weights (30 minutes) on alternate days. I'd like to train for a couple of half marathons that are coming up. I'm just wondering if that's the wrong thing to do if I want to maintain my muscle mass. I'm an endomorph (stocky), so I wouldn't mind decreasing my body fat percentage, but I also want to maintain my muscle mass which is pretty decent. What advice can you give me?

Eat right

 

[Goldfish]

Make sure you eat right (as Habib said) and maintain the resistance training, and you should maintain muscle mass. Endurance training is very unlikely to make you lose muscle mass, but failure to maintain strength training may indeed lead to atrophy.