Sub-4-hour marathon training plan: 16 weeks at 9:09 a mile

A sub-4-hour marathon comes down to one number: 9:09 per mile. This 16-week sub-4-hour marathon training plan is built around that pace. Every workout pace in it is derived from the goal, so you know exactly what each session asks and why.

Who this plan is for

This plan assumes you already have marathon-ready fitness and want to aim it at a time:

• You run about 25 to 30 miles a week and can do five runs a week. Week 1 is 29 miles.
• Your long run is already about 10 miles.
• You have finished a marathon, or at least a half marathon, so you know what long racing feels like.
• A recent race says four hours is realistic. The readiness check below shows how to tell.

If you are running less than that, start with the 16-week marathon training plan, which begins at 20 miles a week and doesn't depend on a time. If this would be your first marathon, a finish-first plan is the better choice. If you have a health condition or haven't had a check-up in a while, see your doctor before starting harder training. Rush University's sports medicine guidance lists chest pain, unexplained fainting, a heart murmur, high blood pressure, a close relative with heart disease before 50, and coronary artery disease over age 35 as reasons to see a doctor first.

The math of four hours

A marathon is 26.2 miles (42.195 km). Four hours is 14,400 seconds:

• Per mile: 14,400 ÷ 26.2188 = 549.2 seconds = 9:09.2 per mile
• Per kilometer: 14,400 ÷ 42.195 = 341.3 seconds = 5:41.3 per km
• Halfway: 2:00:00 at 13.1 miles for an even split

Run 9:09 every mile and you finish in 3:59:54, which is no margin at all. In a real race you weave around other runners and lose seconds at aid stations, so aim to run your marathon-pace work at 9:00 to 9:09 rather than slower. For mile-by-mile and 5K splits, use the marathon splits calculator, or the marathon pace chart for other goal times.

Is sub-4 realistic for you? A race-equivalence check

The most widely used way to compare race times across distances is Peter Riegel's formula:

T₂ = T₁ × (D₂ ÷ D₁)^k

where T is time, D is distance and k is a "fatigue factor". A 2016 study by Vickers and Vertosick in BMC Sports Science, Medicine and Rehabilitation notes that Riegel cited k values of 1.05 to 1.06 for male recreational runners aged 40 to 70 (and 1.08 for elite runners), and that most race-time predictors are built on this formula. Working backward from 4:00:00 with k = 1.06 gives the equivalent times below. The right-hand column does the same for 3:50:00. (Vickers and Vertosick used 1.07 as a middle value in their own tests. It changes little: with 1.07, a 4:00 marathon equals a 1:54:19 half.)

Why the safer column? The same study tested Riegel against the real race times of 2,303 recreational runners and found it was well calibrated up to the half marathon but dramatically underestimated marathon times: for about half of runners, the predicted marathon was 10 minutes or more too fast. Its better-performing models added typical weekly mileage, which was associated with race times at every distance.

So a 1:55 half means sub-4 is possible, especially if your training is consistent. A half around 1:50 means it is likely. If your recent times are slower than the left-hand column, train for a finish or a slower goal this time and come back to sub-4 in the next block.

Your training paces

Every pace in the plan comes from the goal:

The easy and long-run range follows a University of Utah Health physical therapist's advice to run long runs one to two minutes per mile slower than your anticipated race pace, because running them too fast leaves you without enough recovery. Rush suggests at least 30 seconds to a minute slower. On a hot or hilly day, slow down further. The easy pace is a ceiling, not a target.

The 16-week sub-4 plan

Distances are in miles. Monday and Friday are rest days. "10: last 4 @ MP" means a 10-mile run with the final 4 miles at 9:09. Workout totals include an easy warm-up and cool-down. Jog 2 to 3 minutes between repeats.

Week 8 checkpoint. The 9 miles on Sunday include a 10K race or solo time trial with warm-up and cool-down. Compare it with the race-equivalence table: about 52:10 is on track for four hours, 50:00 or faster gives you a margin, and much slower than 52:10 is a reason to rethink the goal before the long runs get serious.

Why it is built this way

Mostly easy, with one workout. A 2024 analysis of 92 published 12-week marathon plans found that they put about 77 to 82% of their distance in the two lowest of five intensity zones, most of it in zone 2, the steady aerobic zone of long runs, and only about 4 to 8% in the two hardest zones. Here, the only hard day is Wednesday, plus marathon-pace finishes on some long runs.

A careful build. The long run rises by 1 to 2 miles at a time, matching the Utah guidance. In a study of 874 novice runners, those who increased weekly distance by more than 30% over two weeks appeared more vulnerable to distance-related injuries than those who added under 10%. The difference was not statistically significant, and the study was exploratory and in newer runners, but the slow build costs nothing. Weeks 4, 8 and 12 are cutback weeks, the reduced-mileage weeks Rush says nearly all plans include.

A 20-miler, not more. In the 92-plan analysis, plans peaking at 65 to 90 km (about 40 to 56 miles) a week had a longest run of 32.5 km (about 20.2 miles) on average. This plan peaks at 45 miles, so a 20-miler is typical. It is run easy in week 13. The marathon-pace practice comes in the shorter long runs around it.

A strict three-week taper. Mileage falls 45, 36, 26, then 12 plus the race. Cleveland Clinic recommends cutting mileage two weeks out by 25 to 50% versus the previous week and roughly halving it again in race week. In a study of 158,117 recreational marathoners, a strict three-week taper, with mileage dropping every week, was associated with a median finish about 5.5 minutes (2.6%) faster than a minimal one-week taper. For a runner on the edge of four hours, that can be the whole difference.

Fuel at marathon pace

A four-hour marathon means about four hours of eating and drinking on the move. A review in Sports Medicine found that 30 to 50% of athletes regularly have gut problems, argues that the gut can be trained, and recommends practicing your race nutrition strategy in training. For exercise beyond about two hours, it suggests up to about 90 grams of carbohydrate per hour from a mix of carbohydrate types, and warns that more than 60 grams an hour from a single sugar source is likely to cause gut trouble.

The marathon-pace long runs in weeks 6, 9, 11 and 14 are your rehearsals: same gels or drink, same timing, at 9:09 pace. Work up toward the amount your stomach handles gradually rather than starting at the top of the range. Our guide to carb loading for a marathon covers the final days. If you have diabetes or another condition that affects how you handle carbohydrate, plan this with your doctor or a registered dietitian.

Race-day pacing for sub-4

• First 5K: settle at 9:09 to 9:15 and let the crowd thin. Don't try to bank time.
• Halfway: about 2:00:00. A minute or two behind is recoverable. Several minutes ahead usually means the first half was too fast.
• Miles 20 to 26.2: this is where the taper and the fueling pay off. Hold the effort, keep eating to schedule.

Adapting it for a sub-3:30 marathon

The same structure works for a 3:30 goal with faster paces. 3:30 is 12,600 seconds, so marathon pace is 12,600 ÷ 26.2188 = 8:00.6 per mile (4:59 per km), and halfway is 1:45:00. Riegel with k = 1.06 puts a 3:30 marathon level with a 1:40:43 half and a 45:39 10K, which gives the workout paces:

The Vickers and Vertosick caution applies here too: Riegel's marathon prediction is often 10 minutes or more too fast, so a half closer to 1:36 gives you a margin (the k = 1.06 equivalent of 3:20 is 1:35:56). The same study linked higher weekly mileage with faster marathons: its model put the difference between training 50 and 30 miles a week at about 25.5 minutes for men and 31.7 minutes for women. If you are chasing 3:30, adding easy miles over several training blocks is a safer lever than making the workouts harder. If 3:30 would get you close to a Boston qualifier, check the current standards on our Boston qualifying times page.