Sub-1:45 Half Marathon — Training Paces and Fitness Profile
Sub-1:45 half marathon is a natural stepping stone for runners who have mastered the sub-2:00 milestone. It requires extending threshold capacity and adding long-run volume — achievable with 3–6 months of structured training for runners who already run consistently.
Quick answer: To break Sub-1:45:00 in the Half Marathon (RPI 42.6), your training paces are: easy 9:27/mi, threshold 7:29/mi, interval 6:33/mi. Equivalent fitness: Marathon 3:37:56, 10K 47:24.
Training paces for Sub-1:45:00 Half Marathon
RPI 42.6 · Goal: 1:44:59 · All paces in min/mile
Calculated from Daniels/Gilbert oxygen cost equations. Easy pace means "this pace or slower."
Equivalent race fitness
These are the predicted equivalent times at other distances for a runner with RPI 42.6 — assuming comparable training for each distance.
Marathon
3:37:56
8:19/mi
10K
47:24
7:38/mi
5K
22:51
7:21/mi
Training approach for Sub-1:45:00 Half Marathon
For sub-1:45 half marathon, threshold training and long runs are the two highest-leverage tools. One threshold session per week (15–20 minutes at threshold pace) and weekly long runs building to 12–14 miles produce the adaptations this standard requires. Easy volume of 25–40 miles per week with genuinely easy recovery days allows the quality sessions to generate improvement.
Calculate your current training paces
The table above shows paces for Sub-1:45:00 Half Marathon fitness. Enter your current race time to see where you are now and how far from the goal you sit.
Training Pace Calculator
These paces are based on your race time — not your body
The Daniels/Gilbert formula predicts training zones from a single race result. StrideIQ goes further: it tracks how your body specifically responds to threshold and interval work — which sessions produce your biggest gains, how quickly you recover, and when your fitness is peaking. Population formulas start the conversation. Your individual response data finishes it.
Common questions
What training paces are needed for sub-1:45 in the half marathon?
For sub-1:45:00 (1:44:59): Easy 9:27/mi, Threshold 7:29/mi, Interval 6:33/mi. RPI 42.6. Threshold at 7:29/mi for 15–20 minutes drives the metabolic adaptation that sub-1:45 racing requires.
Is sub-1:45 realistic for a runner who has done a 2:00 half marathon?
Yes — most runners who have broken 2:00 in the half can reach 1:45 within 12–18 months of structured training. The gap between 2:00 and 1:45 is substantial but bridges consistently with one quality session per week and building long-run volume to 12–14 miles. Patience with adaptation is the primary requirement.
What 10K does sub-1:45 half marathon fitness predict?
Sub-1:45 half fitness (RPI 42.6) projects to approximately 47:24 10K potential. This equivalency check helps confirm whether your aerobic base is tracking toward sub-1:45.
Other goal pace guides
Paces calculated using the Daniels/Gilbert oxygen cost equations (1979). All values derived from the same formula used by the StrideIQ training pace calculator. Goal times use the target-minus-one-second convention (e.g., sub-20 = 19:59 input).