Congratulations on signing up! Twelve weeks is a solid amount of time to prepare for a first half marathon, especially if you can already run comfortably for 20–30 minutes without stopping. The main goals are to gradually build endurance, improve running efficiency, and arrive at race day healthy.
A simple structure that works well for many first-time runners is four runs per week:
| Day | Run | Purpose |
|---|
| Monday | Rest or easy cross-training | Recovery |
| Tuesday | Easy run | Build aerobic fitness |
| Wednesday | Strength training or cross-training | Injury prevention |
| Thursday | Quality workout (tempo, intervals, or hills) | Improve speed and endurance |
| Friday | Rest | Recovery |
| Saturday | Easy run | Add mileage without much fatigue |
| Sunday | Long run | Build race endurance |
Weekly mileage progression
Your long run is the most important workout. Increase it gradually, with a lighter "cutback" week every few weeks.
| Week | Long Run |
|---|
| 1 | 5 miles (8 km) |
| 2 | 6 miles |
| 3 | 7 miles |
| 4 | 5 miles (cutback) |
| 5 | 8 miles |
| 6 | 9 miles |
| 7 | 10 miles |
| 8 | 7 miles (cutback) |
| 9 | 11 miles |
| 10 | 12 miles |
| 11 | 8 miles (start taper) |
| 12 | Race: 13.1 miles |
Easy runs
These should make up most of your training. Run at a pace where you can comfortably hold a conversation. Many new runners make the mistake of running these too fast.
Aim for:
- One easy run of 3–5 miles
- One easy run of 4–6 miles
Increase these gradually as your fitness improves.
Quality workout ideas
Alternate between different workouts:
Tempo run
- 1 mile easy warm-up
- 20–30 minutes at a "comfortably hard" pace
- 1 mile cool-down
Intervals
- Warm up
- 5–8 × 400–800 meters at roughly 5K effort
- Easy jog between repeats
- Cool down
Hill repeats
- Warm up
- 6–10 × 45–90 seconds uphill
- Walk or jog down
- Cool down
You only need one harder workout per week.
Strength training
Two 20–30 minute sessions each week can make a noticeable difference. Focus on:
- Squats
- Lunges
- Deadlifts (or Romanian deadlifts)
- Calf raises
- Glute bridges
- Planks and side planks
Taper
During the final two weeks:
- Reduce your total mileage by about 20–40%.
- Keep a little speed work, but shorten it.
- Don't try to gain fitness—you already have it.
Race pace
For your first half marathon, a smart strategy is:
- Start slightly slower than your goal pace for the first 2–3 miles.
- Settle into your target pace through the middle.
- If you're feeling strong after mile 10, gradually increase your effort.
Fueling
Practice during your long runs:
- Drink water according to thirst.
- For runs longer than about 75–90 minutes, consume 30–60 grams of carbohydrates per hour (such as sports gels or chews).
- Never try new nutrition on race day.
If you tell me:
- your current weekly mileage,
- your longest recent run,
- whether your goal is simply to finish or to hit a specific time,
I can build a personalized 12-week training plan with exact daily distances and workouts.
