By Gerard Donnelly, head coach at TriVelo Coaching and 1988 Australian Ironman Champion, and coach Jordan Donnelly. From the Get Fast Podcast.
A half marathon is 21.1 km. For most of the runners we coach, a good half marathon training plan is built on two key sessions: a long, easy endurance run, with elevation if you have hills where you train, and a midweek hill repeat session. Around those you add easy runs, and later some running at your half marathon pace. Most of the running is easy. What changes from week to week is how long you run, and it goes up slowly. For a beginner, 16 to 20 weeks is still a big task, so give yourself more time if you can. On race day, plan for the first half to feel comfortable.
We don't hand out one fixed half marathon training plan. Our runners are on very similar key sessions, but the volume, the amount of intensity and the starting point depend on the runner. An experienced runner gets some intensity. A newer runner usually starts with none. What follows is how we build a half marathon program for the athletes we coach, so you can build yours the same way.
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It depends on the runner you are today. Our view is that a half marathon 16 to 20 weeks away is still a big task for a beginner runner.
If you already run regularly, a shorter block can work. If you are a beginner, usually not.
Here is one real 20 week example. It is one build for one athlete, and yours depends on where you start. Grant is an athlete Gerard has coached for years as a cyclist. He is a national level time trial rider. He wanted to become a runner and chose a marathon about 16 weeks away. Gerard talked him down to the half marathon. Grant was very fit, but he had done very little running, and a fit person who goes straight into a full running program is likely to get very sore.
| When | What Grant did |
|---|---|
| Start, about 20 weeks out | Some walk running, then easy runs of 20, 30 and 40 minutes once he could run 20 minutes without stopping |
| First 8 to 10 weeks | Kept his cycling for intensity, endurance and leg strength. No endurance running yet, because his body wasn't ready for it |
| When he could run 50 to 60 minutes without getting sore | Less riding, more running. The runs got longer. None of them were hard |
| After that | Hills: hill repeats midweek, and elevation in the weekend endurance run |
| Later in the build | Long runs of 2 hours and 2 hours 30, some tempo runs at half marathon pace, and a practice half marathon that he ran in 1:45, not all out |
| Race day | 1:35, on a windy course that finished with hills |
"At no point were we trying to run hard," Gerard says of Grant's running. "We were just trying to run longer."
Jordan's summary: the result came from being patient at the start.
A 12 week build can suit someone who is already running. Our guest on Ep 307, the elite runner Jimmy Whelan, did a 12 week build for his 61:37 half marathon, after two months of easy jogging first.
For most of our runners we build the week around key sessions. Which ones you do, and how many, depends on you.
Some of our runners want only three to four sessions a week. We give them three to four key sessions, and they run half marathon PBs, some on only 30 to 40 km a week. This works for a period of time. Over six to twelve months you need to bring the endurance and volume back.
Very few of our athletes do interval training on the track. We still see half marathon PBs, for example of four and six minutes, from runners whose training is all strength and endurance. Gerard's view is that hard track sessions such as six by 400 m are mainly for pure runners with 10 to 20 years of conditioning.
The endurance run is the session that stops you fading.
Tom is a TriVelo athlete who shows what this does over time. Three years ago he could not run two hours. We built him up from an 80 minute long run to runs of 2 hours 10 to 2 hours 30, with no real change to his intensity. His half marathon time trials in training over three years went 1:20, 1:18, 1:16, 1:17, 1:17, 1:16, 1:16, 1:17, 1:14 and then 1:13:31. "There is no fast track method," Gerard says. "You have to do the work over a period of time as a runner."
Tom's long runs now have 600 to 850 m of climbing. Don't copy that. He is conditioned to it after years on the same route.
This is one session we use a lot. The numbers below are how we set it up for Grant, as a starting example.
On the first day, pick a marker where the 2 minutes ends. After six or seven weeks you may reach it sooner, for example in 1:52. That shows you are fitter. If your last repeat takes much longer to reach the marker, for example 2:12, you started too hard.
One example of the build: go from four repeats to five to six over three weeks. Have a recovery period with some testing. Then build again to six, seven and eight. The repeats can also be one and a half, two and a half or three minutes.
Your race pace comes from what you have done in training. We are not interested in what you hope to do.
Without data, a casual runner could finish anywhere between 1:40 and 2:20. When we have tested an athlete and have weeks of data, we can predict the time within a couple of minutes, for example between 1:46 and 1:48. That is the value of testing.
Step 1: run a fresh 10 km time trial. As a general guide, double the time, then add minutes for the kind of runner you are. "You just can't double it," Gerard says. A run time trial does not have to be all out unless you are in form and injury free.
| Runner | Add to double your 10 km time |
|---|---|
| Experienced runner, many years of training and many half marathons | 10 to 14 minutes |
| New to running, but with a strong background in another sport | 10 to 14 minutes |
| Mid pack runner | About 14 to 18 minutes |
| New to running, no sporting background | About 22 minutes |
For example, a 40 minute 10 km runner doubles to 80 minutes, and an experienced runner adds 10 to 14 minutes for a half marathon of 1:30 to 1:34. From a 5 km, one example of our formula is that 21 minutes equates to a 44 minute 10 km and a 1:40 half marathon. These are generic equations. They fit the average runner, so some runners will do better and some worse. They only work if you have done the endurance runs. If you have a 10 km time and no endurance training, they do not apply to you.
Step 2: do race predictor sessions. These are not sessions for every week. One way we use them is one a week in a block of about three weeks, then a recovery period, then a repeat with longer efforts.
Step 3: practise in races and over the full distance. We deliberately put Beth into 5 km parkruns, 10 km races and half marathons in the middle of her training block so she could practise execution. Another runner's lead up had a parkrun, a parkrun followed by another 5 km, a 16 km progressive fast run and a 21 km run. That gave her evidence of her pace. A couple of weeks out, many of our runners do a progressive half marathon in training at 95 to 98 percent of race pace, getting quicker as they go. The purpose is to practise execution without a maximum effort.
Then we write the race plan. We ask if you have run this pace in training for a full half marathon, or near to it.
Lucas came to TriVelo after he followed an online half marathon program and got injured in the build up. His PB was about 1:46 or 1:47. After 14 weeks with us he ran a progressive half marathon in training in 1:44. It was a PB, but his first 5 km was far too fast. Two weeks later he raced conservatively early, felt strong in the last 5 km and ran about 1:34.
Grant ran his race the same way. He started at about 4:45 per km and finished at about 4:05 per km.
Sub 2 hours. Beth's goal was to break two hours. Her PB was 2:11. In about four months, with no intense running, she ran 2:00:30. As a guide, we equate a 51 to 52 minute 10 km to about 1:56 to 2:00 for a fresh, well trained runner.
Sub 90 minutes. Gerard's guide is that you need to be a 40 minute 10 km runner to run 90 minutes. If your best 10 km is over 45 minutes, 1:30 is not possible yet. Going from 1:40 to 1:30 is much more achievable than going from two hours to 1:30, which takes longer.
Runners who are close to 1:30 are often running hard all the time and running every run the same. What we change for most of them:
The fitness is built in the months before. If you try to rush the work in the last two, three or four weeks, you are not coming from a good place.
Something we say often: things don't have to go perfectly in the last weeks for you to run well. Jordan's own example is a Gold Coast half marathon. He travelled a lot and barely ran in the last 10 days. He still ran his goal of 1:12, down from 1:14, because the work was already done and he started conservatively.
Our position is that carbohydrate intake is individual. There is no rule such as 90 grams that suits everyone, and you need to experiment.
Our guest Jimmy Whelan shared what worked for him: fuel the night before and have a light breakfast, try a chew if gels don't sit well in your stomach, and eat low fibre food in race week.
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