Calyber is a periodization engine, not a fitness app. It logs your sets, detects performance drift, and recalibrates the next session, with every number traceable to the math it was computed from.
For intermediate lifters who already understand MEV / MAV / MRV, RIR-based progression, and the autoregulation literature, the tooling has been a choice between consumer fitness apps and personal spreadsheets. The first hides the math. The second leaves you doing it by hand. Neither is built for a practitioner who already knows what to measure.
Calyber is the third option: a precision periodization engine with the algorithm in the open. Every prescription shows the basis it was computed from. Every adjustment shows the inputs that triggered it. It works the way an analytical lifter would want a methods section to read.
The autoregulation logic, fatigue indices, and progression model are documented and open to inspection. Every prescription on Calyber surfaces the basis it was computed from. There is no proprietary black box, no AI overlay, no "trust us" layer between the inputs you log and the targets you receive.
The data below is from a real 13-week mesocycle run on Calyber. Not a mockup. 1,068 sets logged across 26 exercises. The algorithm adjusted volume 34 times based on session feedback.
E1RM TRAJECTORY · BENCH PRESS
Upper Body - 2026 · 11 weeks logged
Baseline W3: 95 lbs · Peak W12: 125 lbs · Δ +32%
AUTOREGULATION EVENT LOG · SAMPLE
Showing 5 of 34 algorithm interventions
Each row is an algorithmic adjustment to the next week's volume target, computed from the prior week's soreness, pump, workload, and performance signals.
Athlete identity redacted. Data point counts and volume deltas are unmodified. Source: data/meso-snapshot.json.
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