Muscle Percent - Tracker

Muscle Percentage Tracker

Muscle percentage decides your relative strength. It is the G-factor of athletic ability.

But it’s not just about muscle vs. fat. Much of your body – bones, organs, connective tissue – does not change, and that fixed mass skews the muscle percentage in counterintuitive ways. That’s why “leaner” or “stronger” doesn’t always mean better athletic performance.

Use the tool below to translate changes in weight and waist into three metrics – Health, Athleticism, and Absolute Strength – and see which are improving, stable, or declining.

Inputs

Initial body fat %

Initial muscle %

Weekly measurements of body weight and waist circumference

Advanced settings

Fat (kg) per 1 cm waist change

Default is 1.0 kg ↔ 1.0 cm. Adjust if your waist responds differently.

Weekly Results

X-axis = week. Y-axis = % and kg.

Fat % Muscle % Muscle (kg) Weight (kg)

Notes. These are simplified estimates.

Measurement best practices

Same schedule: Weigh yourself and measure the waist at the same time of day, on the same weekday, each week.
Waist point: Measure at navel level. But if you are fit, you may prefer measuring 1–2 cm below the navel where subcutaneous fat changes are most visible.
Technique: Normal exhale, don’t suck in, keep the tape snug but not compressing the skin.
Scale: After bathroom, before breakfast, minimal clothing.

Deep dive

LÄNGRE TEXT HÄR

Do you improve your body by losing more fat than muscle?