What does my InBody data look like?

• Question Verbatim from You: “What does my InBody data look like?”
• Interpretation of the Question (an attempt to make the question slightly more precise, computable and scientific): What your InBody printout contains: the tests it records and when, what each one measured, and anything in it that looks wrong.

• Time range: 8 InBody tests in 40 days, 2026-09-07 to 2026-10-16, between 06:10 and 09:45.
• Frequency: 1.0 to 11.0 days apart; the closest two, 09-21 and 09-22, are 25 hours apart.
• Quantities: every test records weight, skeletal muscle mass and body fat %; only the last (10-16) is on file in full — 32 figures: body composition, lean mass by segment and impedance. It reads weight 189.5 lb, muscle 101.6 lb, body fat 7.7%.
• Two tests a day apart: 09-21 and 09-22 differ by +2.6 points of body fat, -1.7 lb of muscle and +0.9 lb of weight. Shown as a sense of how far two readings can sit apart, not as a measure of the machine's error.
• Not recorded: what you had eaten, drunk or done before each test.
• Problems found: 3 — 2 medium, 1 low; 3 actions recommended by PerSci. Both are listed at the foot of the page.

• Data sources:
  • InBody270 printout of the 2026-10-16 test, sent as four photos of one sheet. Every figure was typed from the photos by hand, 2026-10-28; the member ID on the sheet was left out.
• Dates: 2026-09-07 to 2026-10-16
• Every value on this page is in tidy.csv beside it.

The three numbers every test on the sheet records, on the same days as the chart above.

The two tests a day apart

Two tests, Monday 09-21 09:09 and Tuesday 09-22 09:45:

+2.6 points of body fat would be about 5 lb of fat in a day. That is not what happened: this is what the same machine reads on the same body a day later, under conditions the sheet does not record. One pair says readings can sit at least this far apart; it does not say how far they usually do.

Test of Friday 2026-10-16 at 06:39, on an InBody270. The machine was told: male, 36, 6 ft 0 in.

Lean mass by segment

The percentage is InBody's: the segment's lean mass against its own standard for your height, which the sheet describes as “compares muscle mass to the ideal”.

Impedance (Ω)

The raw electrical readings every figure above is computed from; kept for comparison with a later test on the same model.

The sheet also recommends a change of +0.0 lb fat and +0.0 lb lean: none.

Every InBody test

• medium — Read by hand from photos of a printout. The composition rows are checked against their own sums below; the history panel has no such check.
  Action 1: Ask the gym whether its InBody account can export every test in full. (see this in ‘Actions Recommended by PerSci’)
• medium — Only the 10-16 test is on file in full; the 7 before it are three numbers each.
  Action 2: Photograph or export each printout when it is made. (see this in ‘Actions Recommended by PerSci’)
• low — Tests at different times of day, 06:58, 08:00, 09:03, 09:09, 09:45, 06:59, 06:10, 06:39.
  Action 3: Test at one time, before food and training. (see this in ‘Actions Recommended by PerSci’)

• ✓ water + dry lean mass + fat mass = weight: 128.3 + 46.5 + 14.7 = 189.5, sheet says 189.5
• ✓ weight − fat mass = lean body mass: 174.8, sheet says 174.8
• ✓ fat mass ÷ weight = body fat %: 7.76, sheet says 7.7 (the sheet's inputs are themselves rounded to 0.1 lb)
• ✓ BMI from weight and the 6 ft 0 in entered: 25.70, sheet says 25.7
• ✓ the history panel's last test is the full test: weight, muscle and fat % all match
• ✓ all 4 time charts on this page share one axis, 2026-09-07 to 2026-10-16