AAAAAH! 700 calories? That's barely what I eat for breakfast.

In 2 hours of riding I would eat the equivalent of 4 gels. (3 clif bloks every half hour) Plus about 2 big bottles of clif shot electrolyte/carb. That's about 600 calories just during my ride. (I tend to ride hard and sweat like mad.)

Managed to lose 50 lbs by eating LOTS and exercising JOYFULLY. What works for you will probably be different, but I really don't think 700 calories is enough to run a body on without it going into crisis-metabolism mode. Let alone trying to exercise on top of that.

I'd recommend eating a nice healthy LARGE dinner, even if it's late. Lots of veges and lean protiens. maybe a nice square of really good dark chocolate with an apple for dessert. mmmmm, chocolate...