Threshold Lab

Athlete setup

Locked during the run — press Reset to edit.

Profile

Engine (trainable)

VO₂max 55 ml/kg/min

Aerobic engine size — trained by intervals + volume

VLaMax 0.56 mmol/L/s

Glycolytic engine — sprint/anaerobic phenotype; how training moves it is still debated

Aerobic base 60 / 100

Training-status index, sedentary → elite — years of easy volume + threshold work

Resulting profile i

LT1 (2 mmol/L)– W

LT2 (4 mmol/L)– W

Pace at LT2–

MLSS (modeled)– W

CP · W′ (modeled)– W

VO₂max power– W

Steady-state lactate vs power. Above LT2 it climbs steeply and runs off the top of the chart at 10 mmol/L.

Modeled power–duration curve i

Highest constant power this athlete holds for each duration, from a fresh start at 12 °C with a full tank and no food or drink. Dashed: CP + W′/duration. Click a point to set it up as a workout.

Muscle fibers

I slow IIa fast-ox IIx fast-gly

Type I (oxidative) 50 %

Type IIa 35 %

Type IIx (glycolytic) 15 %

Fibers set the suggested VLaMax and shift fat-vs-carb use; adjust VLaMax freely after.

Fueling

Glycogen reserve 85 %

Gut absorption 90 g/h

Ceiling on fuel delivery while carbs are in the gut — built by practicing carb intake, not by fitness; delays the wall and raises late-session sustainable pace, never the thresholds

Advanced

Body

Sex

Body fat %

Fuel bias %

Body weight kg

Economy W·min/L

Sweat rate L/h

Max heart rate bpm

Resting heart rate bpm

Conditions

Temperature °C

Humidity %

Altitude m

Aero drag (CdA) m²

Rolling resist. (Crr)

Runner

Pace–

Speed–

Distance0.00 km

Target power

Sprint range 150 W

Below LT1

Heart rate i

48bpm

resting

Blood lactate i

0.9mmol/L

baseline

Perceived effort · Borg i

6/ 20

rest

Energy burn i

              1.4 kcal/min

Carbs –Fat –

Fuel tanks

85%

Glycogen i

340 g · 1394 kcal

−0.0 g/min

100%

Fat i

−0.0 g/min

100%

W′ battery i

full

Gut empty · absorbs ≤ 1.5 g/min (90 g/h)

Burned so far: 0 kcal carbs · 0 kcal fat

Telemetry

simulated — not measured

About the model — what is simplified, and what it can still teach