hattrick

Hello, I know a lot of people who post on these forums are very knowledgeable, so I was hoping that someone could help me with my training schedule. To cut to the chase, I race collegiate mtb xc races every Sat/Sun and I need help making a weekly training schedule that will improve my performance; the only thing I'm worried about is training too hard and thus being tired for the races. The Saturday race is XC which is usually 15-20 miles and the Sunday race is short track for about 40 minutes. My main weakness is coming out too hard early and staying with the leaders and then bonking halfway through - in both events. I have both a road and mountain bike so equipment shouldn't be a problem. I've read some of "The Mountain Biker's Training Bible" which is very enlightening on planning for a season, but for starting the year beforehand and not during! A tentative schedule looks like this:

Monday - MTB 1-2 hours at medium intensity
Tuesday - Hill intervals for 1 hour on the road bike
Wednesday - rest
Thursday - Road or Mountain? I have really no idea here
Friday - light, 1 hour or so MTB ride
Saturday - race
Sunday - race

I guess if I’m having trouble bonking halfway through, I need to work on my base/endurance? Pretty much I'm just looking for all-around improvement and I know that will only come with experience but I'm trying to quicken that process. Any help is greatly appreciated. I'm pretty much lost on whether it is good or not to even train on the road bike at all for mtb and on what lengths/intensity levels I should be aiming for in each workout. I know that this one of those dreaded "help me!" posts and as such, any help is greatly appreciated.