What it takes
A sub 1:45 half marathon means holding 4:58 per km (8:00 per mile) from start to finish. In Jack Daniels' VDOT model, that is a fitness score of about 42.6.
The half marathon pace chart has the splits for it. It also covers every other time from 1:05 to 3:00.
One consistent block of training usually moves a runner a couple of points. So this plan suits someone who runs the half marathon in about 1:49:24 today.
Easy, threshold and interval paces come from that starting point, not from the goal, so you train at the fitness you have.
Sub 1:45 on four days
Sub 1:45 needs 4:58 per km (8:00 per mile). This sample does it on four days, about 43 km at its biggest week. Hill repeats come first, then threshold and short reps, and the race pace work comes last.
In one peak week the long run is 19 km with 5.5 km at half marathon pace at the end. Treat it as a test. If holding 4:58 there feels very hard, you will learn more from that than from any calculator.
On race day, pass 5 km in about 24:50 and 10 km in about 49:40. If you are well ahead of that, ease off: the last 5 km is where an early rush costs most.
Your training paces
Set from a 1:49:24 half marathon, the fitness this plan starts from.
| Pace | What it is for | Per km |
|---|---|---|
| Easy and long | Most of your running. | 6:02-6:19 |
| Threshold | Tempo runs. Comfortably hard. | 5:02 |
| Intervals | Hard repeats with recovery. | 4:37 |
The VDOT chart has the full set, repetition pace included.
The plan, week by week
4 running days a week, peaking at about 43 km. Every fourth week is easier, and a taper leads into race day.
Long runs are on Sunday. Hard sessions are on Tuesday.