I'm still planning to run intervals at the high school track on Saturday. However, I will reduce the intensity of the intervals to give my body more time to adjust to the stress of the speed workout. Last fall I ran just as fast as I did on Saturday and didn't have any problems. Apparently, my winter of LSD reduced the ability of my body to handle the stress of faster running.
On Saturday I will do the following.
1. Do my warm-up and warm-down jogs for one mile instead of the half-mile that I used on Saturday.
2. Only do three or four splits. I didn't count them, but I think I did 6 or 7 splits last Saturday.
3. Reduce each split from a half-mile to a quarter-mile.
4. Keep my recovery jog/walk at a half mile.
5. If I feel that my body isn't handling the splits very well, I will increase the recovery.
6. Use my wife's HR monitor to insure that my interval-pace doesn't cause my HR to exceed 80% and my recovery exceed 70%.
Hopefully, I won't have more problems with tight muscles.