What I meant to post yesterday (but kept getting an error message)
degregorius - friend, that gelatto-like desert has some serious chemistry lab ingredients in it. Can you run a route that takes you past Whole Foods? Michael Pollan's Food Rules changed my life.
Melodylea - I spent 2 day's pay at age 18 on my first Gore-Tex. Well worth it.
jmsab - I held 9.2 MPH for about 1/2 mile yesterday...downhill.
snerb - Good on you for not devoting the dark months to bowling and beer. 15 days until the days get longer!
oshcat - See above, and thanks for the good word.
Jeff - 10:45 is a respectable pace for a 13+ mile training run. My first half marathon was a 10:13 pace.
As far as food on the road, recent research shows that endurance cyclists get peak performance when consuming 90 grams of carbs per hour, in a 2:1 glucose:fructose ratio. Powerbar products have this ratio, Gatorade is 50/50. You'd have to drink 3 pints of gatorade per hour to get the carbs you can use, or 3 packages of Power Bar Energy Blasts, or two packs and 12 oz of Gatorade, which is more reasonable.
I do most of my runs without nutrition. If you can get into the 60-75 minute range, you'll train your body to burn fat instead of glycogen (stored sugars). But I wanted to also train myself for ultra distances, so I started eating real food - PBJs, bananas, oranges - on my LSD days. I ran a series of out and backs and left a cooler in my car. I'd eat 100 calories or so and get back to running, then use GU or gels as a supplement on the trail. I believe my strategy was successful, as I never hit the wall in my marathon, fueling similarly.
EPA estimate only, your mileage may vary. The constant jogging of a runner's digestive tract can add a certain delicacy to the fueling process, but with practice you can figure it out.
On yesterday's run you probably were dehydrated. I try to ingest 2 oz of water per 10 minutes on runs longer than an hour or so. As far as coughing, I used to have that problem, too. In fact, I popped out a hernia while coughing after a run. (Had surgery, I'm in great shape, thanks!). It went away. I'm not sure how much is based on core strength, but I suspect that a stable core supports the diaphragm, easing breathing.
I looked up the marathon you're talking about. http://www.memorialdaymarathon.com/ I doubt it's the toughest in the East, but the elevation profile looks challenging. It's never flat - you are always on a hill, including 2 miles at a 3% grade (downhill at mile 3-4, uphill at 22-23). That uphill is at a Very Dangerous Point in the Marathon, and could break a few spirits if they haven't trained for it. Do some hill work as part of your training, and you'll be OK. And it looks absolutely beautiful.