The Measurement Guide

The measurement guide

How to measure your body for real progress.

The part nobody else gives you. Do this right and your numbers become proof — comparable week to week, month to month, no guesswork.

The one golden rule

Measure the same spot the same way, every time.

Accuracy isn't the tape's job — consistency is. As long as you measure the same site, at the same tension, under the same conditions, the trend is what tells the truth. That's what makes your data trustworthy.

Before you start: set your conditions once.

  • Use a non-stretch tape. A stretchy tailor tape reads differently at every tension.
  • Snug, not compressing. Flat on the skin without digging in.
  • Keep it parallel to the floor. An angled tape reads long.
  • Read at the end of a normal exhale. Don't suck in or puff out.
  • Take two readings per site. Re-measure if they differ by more than ~1 cm.
  • Measure cold & consistent. Morning, before food and training, relaxed (or flexed — always the same).
The six sites at a glance
02Chest01Arm03Waist04Hips / Glutes05Thigh06Calf
Same spot, same way, every time.

The six sites: where to wrap, exactly.

Measuring the upper arm with the GAINSTAPE tape
SITE 01

Arm (biceps)

Thickest part of the upper arm, roughly midway between shoulder and elbow.

TipPick flexed or relaxed and always repeat the same one. Measure cold, never pumped.
Measuring the chest with the GAINSTAPE tape
SITE 02

Chest

Horizontal around the fullest part at the nipple line, level across the shoulder blades in back, arms relaxed.

TipRead at the end of a relaxed exhale so lung volume doesn't skew it.
Measuring the waist with the GAINSTAPE tape
SITE 03

Waist

Around the midpoint between your lowest rib and the top of your hip bone, parallel to the floor.

TipTwo common standards exist — pick one and never switch.
Measuring the hips and glutes with the GAINSTAPE tape
SITE 04

Hips / Glutes

Around the widest part of the buttocks, tape parallel to the floor all the way around.

TipHardest to keep level solo — the auto-lock lets you set it, check the back in a mirror, then read hands-free.
Measuring the thigh with the GAINSTAPE tape
SITE 05

Thigh

Max circumference of the upper thigh, or a fixed point like halfway between hip and knee.

TipA fixed point is easier to repeat than “the widest part,” which drifts as you change.
Measuring the calf with the GAINSTAPE tape
SITE 06

Calf

Widest circumference of the calf, standing relaxed with weight even on both feet.

TipSame side every time — most people have a slightly dominant leg.

How often: measure on a schedule.

Every 2–4 weeks for circumference — the sweet spot for changes to show up. Take two readings per site each session. Keep one set of conditions forever: same time of day, same side, same flexed-or-relaxed choice.

A quick, honest note on “accuracy.”

Different clinical standards place some sites slightly differently, and no home tape is a lab caliper. That's fine — the value here is internal consistency, not clinical precision. As long as you follow one fixed method every time, your numbers are directly comparable to your own past numbers, which is exactly what you need to see progress.

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