Calling all experienced runners!!

Hey guys!!

I am jessica,.. I am a clean eater..have been on this journey for alittle more than 100 days..and I love it.. Have been focused on toning.. but I have been put up to the test to run a 1/2 marathon. So training started TODAY.. and I want to make sure I can hopefully retain my lean muscle while training for this marathon. Any ideas on diet? Increase calories? What should be carbs and protein be at?... I am at 1490calories now.. I have a HRM i burn on avg per workout 500-700 calories with strength and cardio...but now that i will be running I am sure it will be more..Would love to hear feedback thank you. I will also post this on the food/nutrition.

The Inexperienced Runner...

Jessica