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Session assumptions

Steady-state ACSM walking or running equation.

Designed for steady treadmill-like movement without handrail support. Outdoor terrain, wind, gait, fitness, and machine calibration can change actual energy use.

GROSS VS NET

Two legitimate numbers answer different questions.

Gross energy includes the energy you would have used at rest during the session. Net activity energy subtracts that resting component.

Do not automatically “eat back” the result

The daily-needs calculator already incorporates typical training, steps, and work through its activity factor. Adding the entire session estimate to that TDEE can double count activity. Keep the session estimate separate and evaluate intake against a multi-week trend.

Why treadmill readouts differ

Machines may use a different equation, may not know body mass accurately, and cannot fully account for handrail support, calibration, gait, or individual efficiency. Outdoors adds terrain, surface, turns, wind, and changing speed.

Calories to steps is an inverse estimate

Calories and steps are not interchangeable units. This mode first estimates gross energy per minute from speed, grade, and weight, then divides the calorie target by that rate and multiplies by the cadence you entered.

Exercise safety: This calculator does not determine whether an intensity is appropriate. Stop for concerning symptoms and seek qualified guidance when health conditions, medication, pregnancy, disability, or recent inactivity affect exercise decisions.

TRANSPARENT FORMULA

From oxygen cost to kilocalories

walking VO₂ = 3.5 + 0.1 × speed + 1.8 × speed × graderunning VO₂ = 3.5 + 0.2 × speed + 0.9 × speed × gradegross kcal/min = VO₂ × body mass kg ÷ 200

Speed is metres per minute and grade is a decimal. The equations are intended for steady-state conditions. Published evaluations report meaningful prediction error, which is why the output is an estimate rather than a measurement.

Sources and limitations

The calculation uses standard ACSM metabolic equations. The Adult Compendium and independent equation research provide context about activity intensity and prediction limitations.

ACSM Guidelines — equation lineage

Ludlow & Weyand — walking prediction comparison

2024 Adult Compendium — MET context