A.M. 20 x (300 on/100 off) + 1 x 400.
Another middle distance runners theshold workout. 300s were at 6 min/mi pace (68) and 100 jog recoveries were in 40 secs (7:12/mi overall)--40 secs is about the perfect length for the recovery 100 because the average HR almost always ends up identical to that of the reps. The 400 was also at 6 min/mi and was added to total 6400 meters of intervals for the workout.
Average HR for both the reps and jogs were in the mid/upper 170s (LT HRs) for the duration of the workout. Thus, in addition to accumulating 4 miles of training at 6 min/mi, I spent ~38 continuous minutes at LT HRs, which is great for cardiovascular development.
This workout was very comfortable. At rep 17 or 18 my legs just started to feel drained and I had to focus a little more to hold rhythm and good form.
6 days ago I ran 2 x 8 x 300 at a slightly slower average pace but HRs were much higher. My body does well with these workouts and is clearly adapting. | 