Invariant of the Week

Every week, one principle.

One mechanical invariant each week, paired with the techniques that express it and the beliefs it corrects. Browse the archive, subscribe to the RSS feed, or read this week's feature in full.

This week

Week 24, 2026 · Jun 8, 2026

Force Angle Determines Leverage, Not Size

Universal

Force angle — not strength — determines submission leverage. The mechanical foundation of why smaller practitioners can submit larger opponents when the…

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Archive 6

Coming up 47

Scheduled features for upcoming weeks. Each will go live on the Monday of its ISO week.