Half Marathon Time Trial. CIM Prep: 1:08:44 - Seth James DeMoor

Aug 13, 2025

Intro: This is a quick summary of Half Marathon Time Trial. CIM Prep: 1:08:44 from Seth James DeMoor. It’s a great watch — we’re breaking it down so you can try the workout today. Be sure to check out the full video for all the details.

Key Points:

Use a time‑trial or tune‑up race before your main event to test nutrition, gear, and course feel. A formal 10K can be a perfect dress rehearsal, and for those targeting that distance, Mastering the 10K: Proven Training Plans, Pace Strategies, and How a Smart App Can Elevate Your Performance offers excellent guidance on race-day execution.
Simulate race‑day conditions: same breakfast, same clothing, same hydration plan, even the same headband to keep sweat out of eyes.
The CIM course is mostly downhill with about 100 ft of total elevation gain, so expect faster paces on descents.
Track heart rate and power (he averaged 165 bpm, max 173 bpm, power ~328 W) to gauge effort. This data-driven approach is crucial not just for time trials but for all high-intensity sessions. Understanding how to use these metrics is a key part of Mastering Interval Training: Science-Backed Workouts and How a Smart App Can Personalize Them.

Workout Example:

Goal: Run a 13.1 mi (21.1 km) half‑marathon time trial on a downhill‑friendly route.
Target Pace: ~5:00 min/mi (≈3:05 min/km) – the video’s result was 1:08:44 (≈5:13 /mi). Hitting paces this fast requires dedicated speed work. If you’re looking to build your top-end speed, incorporating workouts from our guide on Mastering 5K Speed: Proven Interval Strategies to Cut Minutes off Your Time can be a game-changer.
Structure:
1. Warm‑up 10‑15 min easy jog.
2. Start the 13.1 mi run, keeping nutrition/hydration identical to race day (e.g., carry a drop bag, sip at regular intervals).
3. Finish strong, noting average heart rate and perceived effort.
4. Cool‑down 10 min easy jog/walk.

Practical Tips:

Pack the same breakfast you’ll eat on race day and practice eating it before the run.
Use a hidden drop bag for your phone or valuables, then arrange transport back to the start (as the creator did with an Uber).
Wear a headband or similar gear to manage sweat.
Record heart‑rate and power data to compare with future races.

Closing Note: Try this half‑marathon time trial on a similar course and tweak the paces to fit your current fitness using the Pacing app. It’s a solid way to fine‑tune your race‑day strategy—go for it and enjoy the run