How to Train for a Half Marathon By Running 3 Days a Week

Key runs for half marathon training

Verywell / Theresa Chiechi

Do you want to run a half marathon but don’t have enough time to train? It’s possible to be ready for the 13.1-mile race with just three targeted runs a week. If you stick to this training schedule, it’s also possible you could run your fastest half marathon time.

This 16-week half marathon training plan is based on three specific runs: a tempo run, an interval run, and a long run. You can do the three runs in any order during the week, but the program produces the best results if you allow at least one day in between the key runs. On the other days, you’re encouraged to either cross train, have a complete rest day, or do easy runs.

This program is geared toward runners who’ve run at least one half marathon, have a base mileage of at least 15 miles a week, and can comfortably run up to 8 miles at a time. If you aren’t quite at that level, you may want to try a beginner half marathon schedule. Or, get even more half marathon training plans for different levels and shorter training periods.

You’ll need to have estimates for a couple of key paces in order to do these workouts effectively. The interval and tempo runs are based off your 10K pace, so it’s helpful to have completed a 10K in the past couple of months. You can also use that race time to estimate your target half marathon pace (THMP), or your goal pace. You’ll need the THMP for some of your long runs.

Three Key Runs Per Week for a Half Marathon

These are the three types of runs you’ll need to do each week. The details on exactly how much to run and at what pace for each of those runs are included in the weekly schedule below.

Tempo Run (TR)

Tempo runs help you develop your anaerobic threshold, which is critical for faster racing. For most tempo runs, you’ll start and finish with some miles at an easy, comfortable pace. For the short tempo runs (3 miles or under), you should run at your 10K race pace.

If you’re not sure of your 10K race pace, you should run at a pace that feels comfortably hard. For longer tempo runs (more than three miles), you should run the tempo run portion at your 10K pace plus 15 seconds/mile.

If the 10K pace feels too challenging, another option is to run at a pace between your half marathon pace and 10K pace, ideally starting on the slower end and working your way to the faster end of the pace range.

Long Run (LR)

Some long runs will be done at a comfortable, conversational pace for the designated mileage. Others will be done at a targeted pace, based on your targeted half marathon pace (THMP).

Each long run builds on the next, so it’s important that you get in your long runs each week. If you make big jumps in mileage, you risk getting injured.

Interval Run (IR)

Interval runs are repeats of a certain distance (400m) at your 10K pace and then recovery periods after each interval. For example, 8 x 400m at 10K pace with 90-second recovery in between, would mean running a total of eight 400m repeats with 90 seconds running at easy, recovery pace in between repeats.

Interval runs can be done anywhere, but it’s easier to do them on a track. If you like treadmill running, it’s also convenient to measure your distance and pace on the treadmill.

You should first warm up at an easy pace before starting the intervals. Then, do the intervals/recoveries for the set number of repeats. Finish your intervals with a 10-minute cool-down.

Cross-Training

Cross-training or easy runs can be included in your training as your schedule permits. Cross-training can be any activity other than running that you enjoy, such as cycling, rowing, swimming, yoga, or strength-training. You should do the activity at a moderate intensity.

Strength training has many benefits for runners and is an excellent cross-training option. Aim to do at least one day of strength training per week; two days per week is even better. Your strengthening workout doesn’t have to be too long or intense and can be done without weights or machines, as in this sample workout.

Easy Runs

You can swap out a tempo run or interval day with an easy run from time to time as needed to keep your body feeling strong. Easy runs should be done at a comfortable, conversational pace. You should be able to breathe easily and not be struggling through your run.

Three Days a Week Half Marathon Training Plan

Warm-ups and cool-downs should be done at easy pace. Take at least one complete rest day per week.

Week 1

  • Tempo run (TR): 2 miles easy pace for warm-up; 2 miles at short tempo pace; 2-mile cool down
  • Interval run (IR): 10-minute warm-up; 8 x 400m at 10K pace with 90-second recovery (easy pace) in between; 10-minute cool down
  • Long run (LR): 8 miles at easy, comfortable pace

Week 2

  • TR: 2 miles easy pace for warm-up; 2 miles at short tempo pace; 2-mile cool down
  • IR: 10-minute warm-up; 5 x 800m at 10K pace with 90-second recovery in between; 10-minute cool down.
  • LR: 9 miles at THMP (target half marathon pace) + 30 seconds/mile

Week 3

  • TR: 2 miles easy pace for warm-up; 2 miles at short tempo pace; 2-mile cool down
  • IR: 10 minute warm-up; 4 x 800m at 10K pace + 4 x 400m, all with 90 second recovery in between; 10 minute cool down.
  • LR: 10 miles at easy, comfortable pace

Week 4

  • TR: 2 miles easy pace for warm-up; 1 mile at short tempo pace; 1 mile easy; 1 mile at short tempo pace; 1-mile cool down
  • IR: 10-minute warm-up; 4 x 1200m at 10K pace, with 400m recovery in between; 10-minute cool down.
  • LR: 11 miles at THMP + 30 seconds/mile

Week 5

  • TR: 2 miles easy pace for warm-up; 3 miles at short tempo pace; 1-mile cool down
  • IR: 10-minute warm-up; 6 x 800m at 10K pace, with 90-second recovery in between; 10-minute cool down.
  • LR: 10 miles at easy, comfortable pace, then finish with 2 miles at THMP

Week 6

  • TR: 1-mile easy pace for warm-up; 4 miles at long tempo pace; 1-mile cool down
  • IR: 10-minute warm-up; 10 x 400m at 10K pace with 90-second recovery in between; 10-minute cool down
  • LR: 13 miles at easy, comfortable pace

Week 7

  • TR: 1-mile easy pace for warm-up; 4 miles at long tempo pace; 1-mile cool down
  • IR: 10 minute warm-up; 400m, 800m, 1200m, 1600m, 1200m, 800m, 400m at 10K pace, with 400m recovery in between; 10 minute cool down
  • LR: 11 miles at THMP + 30 seconds/mile

Week 8

  • TR: 1-mile easy pace for warm-up; 3 miles at short tempo pace; 1-mile cool down
  • IR: 10-minute warm-up; 3 x 1600m at 10K pace, with 400m recovery in between; 10-minute cool down
  • LR: 11 miles at easy, comfortable pace

Week 9

  • TR: 1-mile easy pace for warm-up; 5 miles at long tempo pace; 5-minute cool down
  • IR: 10-minute warm-up; 6 x 800m at 10K pace, with 90-second recovery in between; 10-minute cool down
  • LR: 12 miles at THMP + 30 seconds/mile

Week 10

  • TR: 1-mile easy pace for warm-up; 4 miles at long tempo pace; 5-minute cool down
  • IR: 10 minute warm-up; 200m, 400m, 800m, 1200m, 1600m, 1200m, 800m, 400m, 200m at 10K pace, with 400m recovery in between; 10 minute cool down
  • LR: 10 miles at easy, comfortable pace, then finish with 2 miles at THMP

Week 11

  • TR: 1-mile easy pace for warm-up; 4 miles at long tempo pace; 5-minute cooldown
  • IR: 10 minute warm-up; 200m; 400m, 800m, 1200m, 1600m, 1200m, 800m, 400m; 200m at 10K pace, with 400m recovery in between; 10 minute cooldown
  • LR: 10 miles at THMP + 30 seconds/mile

Week 12

  • TR: 2-mile easy pace for warm-up; 3 miles at short tempo pace; 1-mile cooldown
  • IR: 10-minute warm-up; 4 x 1600m at 10K pace, with 400m recovery in between; 10-minute cooldown
  • LR: 14 miles at easy, comfortable pace

Week 13

  • TR: 2-mile easy pace for warm-up; 3 miles at short tempo pace; 2-mile cooldown
  • IR: 10 minute warm-up; 200m; 400m, 800m, 1200m, 1600m, 1200m, 800m, 400m; 200m at 10K pace, with 400m recovery in between; 10 minute cooldown
  • LR: 10 miles at easy, comfortable pace, then finish with 2 miles at THMP

Week 14

  • TR: 1-mile easy pace for warm-up; 4 miles at long tempo pace; 5-minute cool down
  • IR: 10-minute warm-up; 6 x 800m at 10K pace, with 400m recovery in between; 10-minute cool down
  • LR: 12 miles at THMP + 30 seconds/mile

Week 15

  • TR: 1-mile easy pace for warm-up; 4 miles at long tempo pace; 5-minute cool down
  • IR: 10-minute warm-up; 4 x 1600m at 10K pace, with 400m recovery in between; 10-minute cool down
  • LR: 6 miles at easy, comfortable pace

Week 16

  • IR: 10-minute warm-up; 6 x 400, with 400m recovery in between; 10-minute cool down
  • Run 2: 3 miles easy pace
  • Race Day! 13.1 miles at THMP

Half Marathon Racing Tips

To run your best half marathon, you'll also need to be mentally prepared to race 13.1 miles. Get tips on how to win the mental battles during your half marathon. You should also be prepared for some discomfort, especially in the final miles of the race. Here are some tips for dealing with discomfort while racing and for finishing strong.

By Christine Luff, ACE-CPT
Christine Many Luff is a personal trainer, fitness nutrition specialist, and Road Runners Club of America Certified Coach.