Running Plan Review Hal Koerner Ultra: 100 Miles

Does it build you up smartly?

In week 1 the long run is a single 17-miler. By week 17 it's a 35 with a 20 behind it the next day. Between them the weekends grow steadily, from one long run to pairs of 15s, then 25s, and finally the 35. Four lighter weeks break up the climb, and the plan eases off for its last 3 weeks. Those lighter weeks matter more than they feel like they do, because a cutback every few weeks is when the training before it turns into fitness.

The foundation is right for the distance, too. Easy running is the base everything else stands on, and in a 100, nearly every step of the race draws on it.

But the plan has no chapters. Week 3 and week 17 differ in size, not in kind: easy weekday miles and long weekends, from start to finish. Research on training in blocks finds that shifting the emphasis from one block to the next beats holding one kind of training the whole way. For a race this long, much of the work really is aerobic, so a single kind of training costs less here than it would in a shorter race. But over 20 weeks, the plan changes how much it asks of you, never what.

Does it protect you from injury?

Partly. The plan builds its mileage carefully, but it leaves strength work off the schedule.

The build is the good part. Injury risk climbs when a week's running jumps far above what you've been doing, especially past about one and a half times your recent average. This plan never comes close to that, and the lighter weeks keep the load from stacking up. Built gradually like this, more running isn't the risk it looks.

But the miles on the grid don't tell the whole story. A weekend of 25 and 25 is a lot of pounding, and mileage alone misses what terrain, climbing and surface add. If you train on steep trails, a 25-mile run costs your legs far more than 25 flat miles, and the schedule has no way to show that.

The book's training chapter covers strength and core work, but it gives no program and puts none of it on the schedule. How often, what to do, and where it fits around two long days each weekend are up to you. That leaves out one of the better-studied ways to lower injury risk in sport.

The book is strongest on what to do when something starts to hurt. A whole chapter covers self-care and first aid, from blisters and rolled ankles to the serious muscle breakdown that can follow very long efforts. That knowledge helps most on the Monday after a 25-and-25 weekend, when a sore spot could be ordinary tiredness or the start of something. A niggle that lingers between runs often comes before an injury that stops you, and spotting it early lets you back off before the next long weekend makes it worse.

What happens when you miss a day?

In this plan's biggest weeks, a lost weekend isn't a missed run or two. It's 45 to 55 miles, more than half the week's running, gone in two days. What matters then is what you do next.

The book has a clear method for coming back after a setback: run each day's miles in proportion to how recovered you feel, keep an eye on your resting heart rate, and remember that fitness holds for about 2 weeks, so a few missed days cost less than you fear. It also lets you split a day's miles into two shorter runs, and it teaches you to run by feel, with a talk test instead of paces. With no paces to fall behind, a slower week back is still a week on plan.

But the schedule doesn't say which runs to protect when time is short. Most runners will guess the weekend, and they'll be right. It also doesn't say what to do with a long weekend you miss. Squeezing a 25-and-20 into the next weekend, on top of what's already there, is exactly the kind of jump the plan otherwise avoids. Whether to skip it, shrink it or move it is left to you.

Will it get you ready for race day?

Only partly. The plan gets the distance right, but the rest of what a 100 asks is left to you.

The long runs are the plan's strength here. A 35-mile run 3 weeks out, followed by 20 the next day, is serious preparation, and 55 miles in a weekend teaches your body to keep moving on legs that are already worn. For the marathon, long runs that grow over the weeks are something shorter, faster sessions can't replace, and a 100 only raises the stakes. In runners who are already fit, extra mileage pays off mainly in durability and resistance to fatigue, which is exactly what the last third of a 100 demands.

The first gap is rehearsal. The book tells you to practice your race's climbs and night running, and it urges adding training races, but none of that is on the schedule. If your race climbs thousands of feet or runs through the night, the plan doesn't say when to practice either. For a runner eyeing a 100 and wondering whether this plan will get them through a night and a day, that's a lot to work out alone. In many 100s, the climbing and the dark decide the day as much as the miles do.

The second gap is the taper. The running drops from 76 miles to 50, then 47, so the 2 weeks before race week both stay near 50. The bigger drop waits until race week itself, and even that opens with 7 miles on both Monday and Tuesday. A taper of 1 to 3 weeks reliably makes runners faster on race day, but this one cuts only part of the load. You start the race still carrying some of the build's tiredness.

Are the workouts varied enough?

No. Every run in the plan is easy, the 35-miler included.

For 100 miles, that's a more defensible choice than it sounds. A 100 is run far below the efforts that faster training sharpens. Even race-pace practice pays off mainly when race pace sits near one of the body's thresholds, and 100-mile pace sits well below them. Speed isn't what decides a 100.

But how much energy each stride costs you still matters, maybe more than in any shorter race, because you'll take it so many more times. That cost can be trained, and in runners who are already fit, it's one of the most trainable parts of performance. Short, quick efforts like strides and hill sprints help runners use less energy at the same pace, and so does strength training. This plan has none of them. Koerner's plans for shorter ultras use hill repeats, and the book mentions downhill sprints, but the 100-mile schedule leaves them all out.

What variety there is comes from the weekends: single long runs early on, then pairs, then the 30s and the 35. If you train on trails, the terrain adds more. On the page, though, it's easy miles in different amounts, week after week.