Seth's Half-Marathon Threshold

Workout - Seth's Half-Marathon Threshold

• 0.0mi @ 12'00''/mi
• 0.0mi @ 8'00''/mi
• 0.0mi @ 13'00''/mi

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A quick summary of “Naples Half Marathon Training Block FULL Analysis” from Seth James DeMoor.

Seth’s breakdown covers his training approach for the half marathon. Here’s what made the biggest impact, plus a workout you can run today. The full video has more technical detail.

Key training concepts and practical tips

• Volume: Seth ran up to 130 mi/week for three weeks. For racing half-marathon distance, he points to 110 mi/week as the sustainable sweet spot.
• Altitude and vertical gain: mountain runs (Colorado winter) boost red-blood-cell recruitment. Keep high-vertical sessions to 2 per month rather than weekly.
• Speed-ladder/threshold runs: Seth built lactate tolerance with 13–16 mi efforts at 5:20–5:30/mi (at altitude). Early-mid block, he’d break these into 7–9 mi repeats to refine cadence.
• Doubling: back-to-back runs (10 + 10 mi, or 13 + 7 mi) 4–5 days weekly sharpen aerobic capacity and mental grit.
• Long-run pacing: drop by 5–10 % (say, to 6:20–6:25/mi from 6:45/mi) to stay fresh.
• Gym and strength: leg strength declines once you exceed 110 mi/week. Add hip-flexor plyometrics and overall strength work, especially after threshold sessions.
• Race-day listening: watch how competitors are breathing. If your own breathing feels easier, you’ve got better aerobic fitness.

Example workout

Altitude-threshold speed ladder (works on any terrain):

1. Warm-up: 1 mi easy.
2. Threshold run, 7 mi at around 5:20/mi (or 10% slower than your goal half-marathon pace). Stay steady and focus on cadence.
3. Cool-down: 1 mi easy.

If hills or elevation are nearby, run the same effort there.

How to customize

• Use the Pacing app to set the right paces for your current fitness.
• If 110 mi/week is too ambitious, build toward 90–100 mi/week but keep at least one double-run day each week.
• Short on time? Swap the 7–9 mi threshold for a 5 mi speed ladder.

Try the 7–9 mi threshold ladder (or the full 13–16 mi if you’re feeling strong) and work in a couple of double-run days this week. Adjust paces and volume in the Pacing app.

Watch the full video for the complete training block breakdown.

References

• Naples Half Marathon Training Block FULL Analysis: What worked? What would I change? - YouTube (YouTube Video)