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Training plansRunning, explained

21.1 km

Half marathon, second time round.

For anyone who has finished a half and wants the next one to be quicker. More sessions than the beginners’ plans and a longer run at the end of each week, all led by heart rate.

If this is your first, start with the twelve-week plan — this one assumes the miles are already in your legs.

Each run is broken into its parts: the quiet ends are the warm-up and cool-down, the shaded middle is the work. Treat the targets as a guide rather than a rule — they were written for a generic runner, and you are not one.

Week 0

4.8 km10m1 run

  1. 3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

Week 1

17.7 km40m4 runs

  1. Monday

    2 mile zone 13.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  2. Wednesday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  3. Thursday

    2 mile zone 13.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  4. Saturday

    4 mile zone 16.44 km · 10m

    1. Warm Up5 min
    2. Training6.44 km131–150 bpm
    3. Cool Down5 min

Week 2

24.1 km53m5 runs

  1. Monday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  2. Tuesday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  3. Thursday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  4. Friday

    2 mile z1, focus on cadence3.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  5. Saturday

    4.5 mile zone 17.24 km · 10m

    1. Warm Up5 min
    2. Training7.24 km131–150 bpm
    3. Cool Down5 min

Week 3

25.8 km50m5 runs

  1. Monday

    3x 1/2 mile z1, 1/2 mile z24.83 km · 10m

    1. Warm Up5 min
    2. 3 ×
    3. Training0.8 km131–150 bpm
    4. Training0.8 km151–163 bpm
    5. Cool Down5 min

  2. Tuesday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  3. Thursday

    2x1 mile z24.83 km · 10m

    1. Warm Up5 min
    2. Training1.61 km151–163 bpm
    3. Training1.61 km131–150 bpm
    4. Training1.61 km151–163 bpm
    5. Cool Down5 min

  4. Friday

    2 mile z1, focus on cadence3.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  5. Saturday

    5 mile z18.05 km · 10m

    1. Warm Up5 min
    2. Training8.05 km131–150 bpm
    3. Cool Down5 min

Week 4

23.3 km53m5 runs

  1. Monday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  2. Tuesday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  3. Thursday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  4. Friday

    2 mile z1, focus on cadence3.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  5. Saturday

    4 mile zone 16.44 km · 10m

    1. Warm Up5 min
    2. Training6.44 km131–150 bpm
    3. Cool Down5 min

Week 5

29 km50m5 runs

  1. Monday

    3x 3/4 mile z1, 1/4 mile z34.83 km · 10m

    1. Warm Up5 min
    2. 3 ×
    3. Training1.21 km131–150 bpm
    4. Training0.4 km164–169 bpm
    5. Cool Down5 min

  2. Tuesday

    2 mile z1, focus on cadence3.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  3. Wednesday

    2 mile z1, 2 mile z26.44 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Training3.22 km151–163 bpm
    4. Cool Down5 min

  4. Friday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  5. Saturday

    6 mile zone 19.66 km · 10m

    1. Warm Up5 min
    2. Training9.66 km131–150 bpm
    3. Cool Down5 min

Week 6

31.4 km53m5 runs

  1. Monday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  2. Tuesday

    4x 1/2 mile z1, 1/2 mile z36.44 km · 10m

    1. Warm Up5 min
    2. 4 ×
    3. Training0.8 km131–150 bpm
    4. Training0.8 km164–169 bpm
    5. Cool Down5 min

  3. Thursday

    4 mile zone 16.44 km · 10m

    1. Warm Up5 min
    2. Training6.44 km131–150 bpm
    3. Cool Down5 min

  4. Friday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  5. Saturday

    3 mile z1, 3 mile zone 29.66 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Training4.83 km151–163 bpm
    4. Cool Down5 min

Week 7

33.8 km50m5 runs

  1. Monday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  2. Tuesday

    1 mile z1, 3 miles z26.44 km · 10m

    1. Warm Up5 min
    2. Training1.61 km131–150 bpm
    3. Training4.83 km151–163 bpm
    4. Cool Down5 min

  3. Thursday

    5 miler with strides8.05 km · 10m

    1. Warm Up5 min
    2. 5 ×
    3. Training1.45 km131–150 bpm
    4. Training0.16 km170–178 bpm
    5. Cool Down5 min

  4. Friday

    2 mile z1, focus on cadence3.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  5. Saturday

    7 mile z111.27 km · 10m

    1. Warm Up5 min
    2. Training11.27 km131–150 bpm
    3. Cool Down5 min

Week 8

29 km56m5 runs

  1. Monday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  2. Tuesday

    4 mile zone 26.44 km · 10m

    1. Warm Up5 min
    2. Training6.44 km151–163 bpm
    3. Cool Down5 min

  3. Thursday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  4. Friday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  5. Saturday

    6 mile zone 19.66 km · 10m

    1. Warm Up5 min
    2. Training9.66 km131–150 bpm
    3. Cool Down5 min

Week 9

38.6 km50m5 runs

  1. Monday

    2x1 mile z1, 1 mile z36.44 km · 10m

    1. Warm Up5 min
    2. 2 ×
    3. Training1.61 km131–150 bpm
    4. Training1.61 km164–169 bpm
    5. Cool Down5 min

  2. Tuesday

    4 miler with strides6.44 km · 10m

    1. Warm Up5 min
    2. 4 ×
    3. Training1.45 km131–150 bpm
    4. Training0.16 km170–178 bpm
    5. Cool Down5 min

  3. Thursday

    5 mile z28.05 km · 10m

    1. Warm Up5 min
    2. Training8.05 km151–163 bpm
    3. Cool Down5 min

  4. Friday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  5. Saturday

    6 mile z1, 2 mile z212.87 km · 10m

    1. Warm Up5 min
    2. Training9.66 km131–150 bpm
    3. Training3.22 km151–163 bpm
    4. Cool Down5 min

Week 10

43.5 km50m5 runs

  1. Monday

    4 mile zone 16.44 km · 10m

    1. Warm Up5 min
    2. Training6.44 km131–150 bpm
    3. Cool Down5 min

  2. Tuesday

    4x1 mile z3, 1/2 mile z19.66 km · 10m

    1. Warm Up5 min
    2. 4 ×
    3. Training1.61 km164–169 bpm
    4. Training0.8 km131–150 bpm
    5. Cool Down5 min

  3. Thursday

    5 mile z28.05 km · 10m

    1. Warm Up5 min
    2. Training8.05 km151–163 bpm
    3. Cool Down5 min

  4. Friday

    3 miler with strides4.83 km · 10m

    1. Warm Up5 min
    2. 6 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km170–178 bpm
    5. Cool Down5 min

  5. Saturday

    9 mile z114.48 km · 10m

    1. Warm Up5 min
    2. Training14.48 km131–150 bpm
    3. Cool Down5 min

Week 11

48.3 km1h 0m6 runs

  1. Monday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  2. Tuesday

    6 mile z29.66 km · 10m

    1. Warm Up5 min
    2. Training9.66 km151–163 bpm
    3. Cool Down5 min

  3. Wednesday

    2 mile zone 13.22 km · 10m

    1. Warm Up5 min
    2. Training3.22 km131–150 bpm
    3. Cool Down5 min

  4. Thursday

    6 mile zone 19.66 km · 10m

    1. Warm Up5 min
    2. Training9.66 km131–150 bpm
    3. Cool Down5 min

  5. Friday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  6. Saturday

    5x 1 mile z1, 1 mile z216.09 km · 10m

    1. Warm Up5 min
    2. 5 ×
    3. Training1.61 km131–150 bpm
    4. Training1.61 km151–163 bpm
    5. Cool Down5 min

Week 12

34 km41m4 runs

  1. Monday

    3 mile zone 14.83 km · 10m

    1. Warm Up5 min
    2. Training4.83 km131–150 bpm
    3. Cool Down5 min

  2. Wednesday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  3. Friday

    2.5 miler with strides4.02 km · 13m

    1. Warm Up5 min
    2. 5 ×
    3. Training0.64 km131–150 bpm
    4. Training0.16 km4:01–4:01 /km
    5. Cool Down5 min

  4. Saturday

    Half Marathon Day!21.1 km · 5m

    1. Training21.1 km151–163 bpm
    2. Cool Down5 min

Plan by COROS, set out here so it can be read without an account. The wording around it is ours.