I have begun doing all of my quality work on roads. I do this because I am mainly a road racer and because access to the tracks near where I live is restricted and often not available when I have a workout planned.
I have found a nice long straightaway road in which I can do my 1k repeats (or shorter, although I rarely do shorter than 1k repeats). The road has a little wave to it but nothing I would call an actual hill, but standing at one end and looking down toward the other you can tell there is a little elevation change. Typically I have noticed that its about 4-5 seconds faster one way than the other on an even effort. Today I looked it up on mapmyrun.com and it says there is a 15 meter (52 ft) evelation difference betwwen one end and the other making for a grade of about 1.5% (am I calculating that correctly - rise/run). Is this type of small grade big enough to change the effectiveness (for the better or worse) of the workout for me or the systems I'm working.
I also do my longer repeats (1 mile - 5 mile) on different road loops which are rolling in nature with a few decent but not huge hills in them. Most of the race I run where I live are rolling courses so I always assumed doing my workouts on similar terrain was advantagous. Are there any drawbacks to doing things this way? For example because of the hills my heart rate is not as steady througout the repeats as it would be on a track, so may rise above or drop below the desired work zone briefly a couple of times during my repeats.
Any thoughts on this.