Low-end Tempo Run

Yesterday was my first tempo run in a 3 week cycle.  In an effort to increase my endurance and stamina I am going off "track" and hitting the road for some real race training.  Instead of intervals at the track I am focusing on tempo runs and road endurance.  This was inspired by an article in Running Times the Full Spectrum of Lactate Threshold Training.  The basic idea of the program is that doing three different styles of LT training will help to boost overall performance.  I decided to do a 3 week cycle incorporating each cycle and keep repeating to building up my LT endurance.
So yesterday was week 1 - Low-end Tempo Run.  This is a slower pace - closer to a marathon goal pace.  This seemed so easy to me.  I've never run races of this distance so I felt like I was crawling. This is the pace that I normally do my long runs, not a 45 minute tempo run.  Yep - that is exactly what I thought.  Well apparently all the breaks and slow downs I take in my long runs makes me soft because the 45 minutes was tough.  I do need to blame the weather and my low calorie intake a bit for this, but by the end of the 45 minutes my legs were struggling.  I was holding my pace about 10 seconds per mile faster then intended (9:50), but it was still a slower pace as I'm concerned for a tempo.
Over the weeks my goal will be to add to the distance of the pace.  Even when I'm into my 1/2 training I want to keep this on my schedule to keep me going at a steady hard pace with no breaks.  Every week I will add approximately 10 minutes to the previous week total.  probably when I get to 65 minutes I will hold for a week and decrease pace some, not sure on that.
I'm interested to see how this will affect my ultimate training goal of the marathon next Winter, as I will need to be able to hold this pace for a good 4 hours, not the 2 hours I am use to on weekends.  Only time will tell how effect this will be.

To round out my week I will pair this tempo run with a progressive long run.  My goal is to train my body to run negative splits better on race day.  My horrible habit of going out to fast has got to go. This week will be an 8 miler with pace ranging from 10:30 for the first two miles to 9:30 by the end.  The slower tempo run mid week should keep my legs fresh enough to hit this easily.