18-Week Half Marathon Training Schedule

Designed for beginners, injury-prone runners, or people with a busy schedule, this 18-week training plan allows you to run four days per week and build up to 13.1 miles in a more gradual manner.

This plan is much like our 16-week training plan – in fact, it’s virtually the same plan, with two extra weeks added in, as well as some slight changes to the long runs. You’ll alternate between adding a mile each week to your long runs, and repeating it the next week.

Keep in mind if you’re already running consistently and want to move your body five days per week, you can make Wednesdays an easy-run day or use that day to crosstrain (more on that later), says Becky Wade Firth, a pro-marathoner, cross-country running coach, and HMG writer.

With 18 weeks of training, it’s important to stay consistent, injury-free, and motivated. Follow this guide for distances, but if you’re looking for more personal coaching, we recommend Runna. Runna is as good as having a coach in your pocket. Use code HALF for 2-weeks free.

18-Week Half Marathon Training Plan

For a Saturday Race

Week	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
1	Off	3 miles	Off	3 miles	Off	3 miles	3 miles
2	Off	3 miles	Off	3 miles	Off	4 miles	3 miles
3	Off	4 miles	Off	4 miles	Off	5 miles	3 miles
4	Off	4 miles	Off	4 miles	Off	5 miles	3 miles
5	Off	5 miles	Off	5 miles	Off	6 miles	2-3 miles
6	Off	5 miles	Off	5 miles	Off	6 miles	2-3 miles
7	Off	6 miles	Off	4 miles	Off	7 miles	2-3 miles
8	Off	6 miles	Off	4 miles	Off	7 miles	2-3 miles
9	Off	5-6 miles	Off	4-5 miles	Off	8 miles	2-3 miles
10	Off	5-6 miles	Off	4-5 miles	Off	8 miles	2-3 miles
11	Off	6 miles	Off	5 miles	Off	9 miles	2 miles
12	Off	6 miles	Off	5 miles	Off	9 miles	2 miles
13	Off	5-6 miles	Off	4-5 miles	Off	10 miles	2 miles
14	Off	5-6 miles	Off	4-5 miles	Off	10 miles	2 miles
15	Off	5-6 miles	Off	4-5 miles	Off	11 miles	3 miles
16	Off	5-6 miles	Off	4-5 miles	Off	12 miles	2 miles
17	Off	5-6 miles	Off	4-5 miles	Off	6 miles	3 miles
18	Off	4-5 miles	Off	4-5 miles	Off	13.1 miles	Off

For a Sunday Race

Week	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
1	Off	3 miles	Off	3 miles	Off	3 miles	3 miles
2	Off	3 miles	Off	3 miles	Off	3 miles	4 miles
3	Off	4 miles	Off	4 miles	Off	3 miles	5 miles
4	Off	4 miles	Off	4 miles	Off	3 miles	5 miles
5	Off	5 miles	Off	5 miles	Off	2-3 miles	6 miles
6	Off	5 miles	Off	5 miles	Off	2-3 miles	6 miles
7	Off	6 miles	Off	4 miles	Off	2-3 miles	7 miles
8	Off	6 miles	Off	4 miles	Off	2-3 miles	7 miles
9	Off	5-6 miles	Off	4-5 miles	Off	2-3 miles	8 miles
10	Off	5-6 miles	Off	4-5 miles	Off	2-3 miles	8 miles
11	Off	6 miles	Off	5 miles	Off	2 miles	9 miles
12	Off	6 miles	Off	5 miles	Off	2 miles	9 miles
13	Off	5-6 miles	Off	4-5 miles	Off	2 miles	10 miles
14	Off	5-6 miles	Off	4-5 miles	Off	2 miles	10 miles
15	Off	5-6 miles	Off	4-5 miles	Off	3 miles	11 miles
16	Off	5-6 miles	Off	4-5 miles	Off	2 miles	12 miles
17	Off	5-6 miles	Off	4-5 miles	Off	3 miles	6 miles
18	Off	4-5 miles	Off	4-5 miles	Off	Off	13.1 miles

About This Training Schedule

Who It’s for

This training plan is for beginner to intermediate runners who have a long lead time (at least 18 weeks) till their target half marathon or who want to minimize their injury risk with a gradual build. You should already be running a few miles a few days per week, which will have laid a strong foundation you can build on in this plan. 

Injury Prevention

An 18-week training plan allows for a gradual build-up of mileage, which is great for reducing your risk of overuse injuries like shin splints and plantar fasciitis. With this longer timeframe, you have a great opportunity to focus on injury-prevention strategies from the start, ensuring your tendons, ligaments, and muscles are well-prepared for the demands of half marathon training. 

That said, injuries can happen to any level of runner, and we’re here to minimize the risk and maximize training. Try these tactics:

1. Incorporate regular cross-training. On at least one non-running day per week (Wednesdays, in this plan), try cycling or swimming or another low-impact activity to maintain cardiovascular fitness while giving your body a break from repetitive impact. Cross-training can also improve overall strength and reduce imbalances.
2. Respect rest days. With an 18-week plan, rest days are essential for preventing burn-out and keeping your body in one piece. Proper rest allows your muscles to recover and helps prevent overuse injuries. For active recovery, try light walks, stretching, or gentle yoga to stay loose without overstressing your body.
3. Make strength training a priority. An 18-week build-up allows plenty of time to establish a consistent strength routine, if you don’t have one already. Try to get in one to two 30-minute sessions per week with dumbbells or kettlebells. Focus on exercises that build power and stability, particularly in the glutes, core, and lower legs. This not only boosts running performance but also fortifies muscles and joints against injury.

What to Eat

Proper half marathon nutrition is what fuels your runs. What you eat helps to maintain energy, enhance performance, and promote recovery. 

• 50% carb for primary fuel
• 25% protein for muscle repair
• 25% fat to sustain longer efforts.

Daily meals should feature whole grains, fruits, lean proteins, and healthy fats. For shorter runs (under an hour), your regular diet should suffice, but for longer runs (over an hour), increase carbs the day before to ensure glycogen reserves.

For runs longer than an hour, take in mid-run carbs (30-60 grams per hour) from gels, chews, or sports drinks. After running, a 4:1 carb-to-protein recovery meal like a smoothie with protein powder will help you recover faster and prep for your next run.

More Half Marathon Training Plans

8 Weeks • 9 Weeks • 10 Weeks • 12 Weeks • 14 Weeks • 16 Weeks • 20 Weeks

–

We independently produce all the content associated with training plans we feature on HalfMarathons.net. If you buy or sign up for services through the links on our site, we may receive an affiliate commission – which in turn supports our work.