How do you decide paces for workouts? Although it’s convenient to use workout pace tables, you need to understand what’s behind the numbers before blindly following what they say.
For example, the VDOT tables of Jack Daniels and his former athlete and computer programmer Jimmy Gilbert are popular among coaches and runners. Those numbers are computer-generated based on regression equations. To come up with the workout paces, it’s assumed that every runner has the same running economy (which is not true) and that every runner is equally as good at all racing distances (also not true). I have found the paces to be more accurate for very good and elite runners than for recreational runners.
Let’s look at an example: For a runner who runs a half-marathon in 1:00:54 (4:38/mile pace), that equals a VDOT of 80 and a corresponding pace of 4:41/mile for threshold (tempo) workouts. For a runner who runs a half-marathon in 1:50:59 (8:28/mile pace), that equals a VDOT of 40 and a corresponding pace of 8:12/mile for threshold workouts.
For the runner who runs 4:38/mile pace for a half-marathon, I agree that threshold pace is 4:41/mile because threshold pace will be very close to or right at half-marathon pace for someone who runs a half-marathon in 1 hour. From my own lab research, I have seen that very good runners can maintain threshold pace for about 1 hour. However, the runner who runs 8:28/mile pace for a half-marathon will not likely have a threshold pace of 8:12/mile because that means he/she will be running for 1 hour and 51 minutes at a pace that’s only 16 seconds per mile slower than threshold. It’s difficult to imagine that someone who runs a half-marathon in 1:51 runs only 16 seconds/mile slower than threshold for 1 hour and 51 minutes, especially when someone who runs a half-marathon in 1:01 runs 3 seconds/mile faster than threshold (a 19-second/mile difference relative to threshold—16 seconds slower vs. 3 seconds faster).
Bottom line? Don’t just blindly follow a pace table. Acquire expertise about training and you can design workouts to fit your abilities and needs. Where can you acquire that expertise? I’m glad you asked. revo2lutionrunning.com