Truth Tuesday: January 19th, 2010

Exercise: What your workout plan does to your brain. From the wiring in your brain to the blood rushing through your veins, Women's Health explains its effects

Dimity McDowell

Ready? Set! Know! Putting your body through its paces is like driving a stick: It's much easier to master if you understand exactly how a car zips from zero to 60. I know how my body feels when I'm gunning hard during a workout plan or a race (can you say "Shoot me now!"?), but I have no clue what's really making it go. So I dialed up the nation's leading fitness experts to find out, blow by painful blow, exactly what was happening to my body during my most recent race, the Boulder Peak Triathlon, this past July.

Apply their tips to your next workout, whether it's a killer strength training session, a spin class, or a day on the slopes, and you'll get a new appreciation for what your hardworking body can do--and a killer performance boost to go with it. And find out what to eat before your day's biggest tasks in WH's "Your Secret Power Foods."

Fueling Up

4:45 a.m. It's two hours before the race starts. I force down two slices of whole-wheat toast with a thin layer of peanut butter and a sliced banana on top. What's going onEating is the last thing I want to do, but I have to nosh now because my stomach needs time--two hours, to be exact--to digest complex carbs. Once I'm in motion, digestion will all but stop, so my belly will get no love from my body's oxygen-rich blood, which it needs for digestion.

"The nervous system directs blood to where it's needed most," says Carol L. Otis, M.D., co-author of The Athletic Woman's Survival Guide. During a hard physical effort, the muscles that move my body crave oxygen and demand nearly 85 percent of my blood flow. The O2 combines with glycogen (a byproduct of carbs) to produce adenosine triphosphate, aka ATP. That's the fuel that makes the body go. Knowledge is power At least 80 percent of your pre-workout meal should be carbs. Try cereal with milk and a banana, or an English muffin with almond butter and honey.

Prone to stomach issues? "Drink a carb-rich sports drink like Gatorade or a smoothie made with fruit and low-fat yogurt--they're easier to digest," says Ilana Katz, M.S., R.D., a sports nutritionist in Atlanta.