With two halfs on my race calendar, and my tubes of nuun in hand, I'm set. I'm finding that it isn't always what I eat that affects me (don't get me wrong, it does), but how I'm hydrating myself that really plays out in my workouts. After running around 5J or sitting by a patient's bed for 8 hours and then working out OR working out and then working the evening shift, my body tells me how much it loves me according to its hydration status. Nuun is a lifesaver. Nuun was a "sponsor" for the crew team freshmen year. It was addicting, pure hydration, sugar-free, full of electrolytes, and free. I think it goes for around $12 per tube. Therefore, free is good. Tubes and tubes of nuun. I would drink nuun ALL THE TIME. My nuun of choice is tri-berry. Nuun is not an "energy drink." It is purely electrolytes; which equals maximum hydration without drinking litres and litres of water (which is perfect for rowers [especially lt. weights]).
Check nuun out . . . http://www.nuun.com/index.php
The only downside. Each time I reach a running high, my what used to be a seemingly neverending nuun supply . . . is no longer neverending.