The Yigri guidebook
Understand what your running is telling you.
Clear, source-backed answers and comparisons for the moments when pace, heart rate, weather, training, or equipment make a run harder to read.
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Guides for better comparisons
Start with the question that showed up in your last run.
answer · training
A beginner half-marathon plan for runners with a base
A 12-week first-half-marathon framework with clear starting requirements, recovery weeks, and changes to make when training does not go to plan.
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answer · training
COROS Running Fitness vs Base Fitness: why the scores can move differently
Understand COROS load and running estimates, activity eligibility and post-test zone changes without chasing a preferred score.
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answer · training
Garmin says unproductive, but my running is improving: what should I check?
Make sense of Garmin's Unproductive label by checking its inputs, eligible runs and your measured performance, with a simple 5 km example.
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answer · shoes
How carbon-plated shoes change workout comparisons
Why pace and heart-rate trends can shift after a shoe change, and how to compare workouts without crediting every difference to fitness.
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answer · weather
How heat affects running pace
Why the same effort can produce a slower pace in warm conditions, and how to compare hot-weather runs without mistaking weather strain for lost fitness.
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answer · performance
Marathon and half-marathon pace calculator
Convert a finish-time goal into kilometer or mile pace and checkpoint times, with the exact finish distance and clear rounding.
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answer · training
What happens to fitness during a marathon taper
What a marathon taper changes, how two and three weeks compare, and how to read the final runs without turning them into a fitness test.
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answer · performance
How to run a negative split
What a negative split means, how to calculate it, and when even effort is more useful than faster second-half pace.
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comparison · training
Treadmill vs outdoor running pace
What treadmill pace and outdoor pace have in common, where they differ, and why one conversion rule cannot settle the comparison.
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answer · performance
Why heart rate is higher at the same running pace
How to interpret a higher heart rate at a familiar pace using weather, hydration, route, fatigue, and comparable runs.
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answer · performance
Why running pace slows on hills
Why uphill pace can drop at the same effort, and how to compare hilly runs without treating every slow split as lost fitness.
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