QT2 Systems QT2 Systems
QT2 Systems Training Calculators
Training Calculators

Science-based tools to help you train smarter.

Critical Power, VO₂ intervals, training zones, CHO burn, swim pacing and more — for bike, run and swim. Pick any calculator, or let our AI coach assistant choose the right one for your question.

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Planning · External
Block Prescription Tool
Threshold-state driven training-block selection with lactate curve modeling and block simulation — see projected adaptation before you prescribe. Exports to PDF.
Run · External
Heat & Humidity Adjuster — Run
Adjust your target running pace, power and heart rate for conditions warmer or more humid than you've acclimated to — so your session intensity stays true in the heat.

Bike

Bike
Critical Power (Bike)
Enter a 3-minute and a 12-minute effort and get your Critical Power, W', pVO₂max, fiber-type mix and full bike power zones — the foundation of every bike prescription.
Bike
Best Effort Wattage Intervals
Given your CP and W', predict the maximum wattage your athlete can sustain over 3, 5, 10, 20, 30, 60-minute (or custom) intervals — for prescriptions and race pacing.
Bike
VO₂ Max Intervals — Bike
Prescribe VO₂ max intervals on the bike with exact target watts, work/rest ratios and session totals — built from Critical Power and W' inputs.
Bike
Bike Power Zones — Expanded
A full breakdown of bike power zones with sub-zones (Sweet Spot, Z2 high/low, anaerobic tiers) — from one CP input, ready to drop into your training plan.
Bike
Low Cadence Calculator
Build strength-endurance prescriptions at low cadence — target watts and cadence windows adjusted from your Critical Power for a purposeful high-torque session.

Run

Run
Critical Speed (Run)
Enter a 3-minute and a 12-minute run effort and get your Critical Speed, D', vVO₂max and full run pace zones — the run equivalent of Critical Power.
Run
Best Effort Pace Intervals
Given Critical Speed and D', predict the best pace your athlete can sustain over standard or custom interval durations — essential for track sessions and race pacing.
Run
VO₂ Max Intervals — Run
Prescribe VO₂ max run intervals with exact target paces, work/rest ratios and session totals — built from Critical Speed and D' inputs.

Swim

Swim
Critical Speed (Swim)
Enter two swim time-trials (e.g. 400m and 200m) and get your swim Critical Speed, D' and full swim pace zones — anchor every pool set in real thresholds.
Swim
Swim Interval Pacing
Plan swim sets with target split times per 50m / 100m across different zones — converted directly from your swim Critical Speed.

Nutrition

Nutrition · Bike
CHO Burn — Bike
Estimate carbohydrate burn rate (g/hr) for a bike session by duration and intensity factor — the starting point for in-session fueling strategy.
Nutrition · Run
CHO Burn — Run
Estimate carbohydrate burn rate (g/hr) for a run session by duration and intensity — essential for long-run and race-day fuel plans.
Nutrition · Swim
CHO Burn — Swim
Estimate carbohydrate burn rate (g/hr) for a swim session by duration and intensity — useful for long open-water sets and triathlon fueling plans.

Zones & Reference

All sports
Training Zones (Bike · Run · Swim · HR)
One-stop reference: enter CP, CS or LTHR and get a clean zone chart for bike power, run pace, swim pace and heart rate — plus HR calibration to Critical Power.