What does it all mean?

I am starting week 7 of the Breast Cancer Beta Fitness Study and I am not sure what all this means however I am following along on what they have asked me to do. Here is what I have done so far:

Week 1 - Exercise 3 days per week - Heart Rate 111 - 114 for 10 - 15 minutes
Week 2 - Exercise 3 days per week - Heart Rate 111 - 117 for 10 - 15 minutes
Week 3 - Exercise 3 days per week - Heart Rate 114 - 122 for 15 - 20 minutes
Week 4 - Exercise 3 days per week - Heart Rate 117 - 126 for 15 - 20 minutes
Week 5 - Exercise 4 days per week - Heart Rate 117 - 126 for 15 - 20 minutes
Week 6 - Exercise 4 days per week - Heart Rate 124 - 131 for 20 - 25 minutes
My last workout on Week 6 my average heart rate was 129 and I worked out 25 minutes

I am starting today:
Week 7 - Exercise 4 days per week - Heart Rate 124 - 131 for 20 - 25 minutes

In depth information about this study is listed below. Click on the words below to go to the link:

Beta Breast Cancer Study Information

I really have no idea what changes this is making on my body so I am finding that although I am going through the motions that it is not very motivating since I do not see any results other than I am working harder and longer. I am feeling a bit nervous about not seeing any results. I am concerned that I am going to loose my momentum because like most people I equate hard work with results. I am doing the hard work (for me anyhow) however there is no real way to judge any results and after doing 7 weeks of this work out one would assume that there must be some results but how can I measure them?

You say, check the scales. Not that is not a real indication of results because the sad part is that if you burn fat and build muscle that muscle weighs more than fat so I am afraid to weigh myself in case I weigh the same or more after all this hard work. I could actually weigh the same more and that would be devastating.

Oh well, I have to realize that this study is about breast cancer and that it is proven from the beta study that doing 30 minutes of aerobic exercise a day reduces the factors by 30 or 40%. There is a benefit but I can't see it.

Latest number of women participating in this study are that there are 180 ladies with 147 in Calgary and 33 in Edmonton so far. The numbers are slowly going up.