Your measurements, trended over time
Log a weigh-in, sync a smart scale or enter tape measurements, and MuscleBuddy trends them and shows where each number goes. It leaves the question of what a number says about you to you.
Informational only, not medical advice. Consult a qualified clinician before changing medication, hormones, or supplements.
A rolling average under the daily readings
Day to day, water, sodium and digestion move the scale more than fat or muscle do. MuscleBuddy logs each entry and shows a rolling 7-day average, so you can see the direction under the daily swings.
Weight comes in by manual entry or smart-scale sync, and each row is tagged with its source (manual, synced, estimated or imported). Nutrition reads the same weigh-ins, comparing your last seven with the ones before them, to decide when your calorie and macro targets move.
Body fat: measured, synced, or estimated
Body fat percentage can come from a smart scale, from a DEXA or InBody-style scan (weight, body fat, skeletal muscle mass, fat-free mass, visceral fat level, body water percentage, bone mass, metabolic age, BMR, and bone density T- and Z-scores where your scan reports them), or from one of two estimators in the app: the Navy method (waist, neck and hip circumference) and Jackson-Pollock skinfolds. Estimator results are labelled as estimates.
Each metric gets its own trend line on the body composition page, so you can watch one value move over months.
Tape measurements and bilateral symmetry
Waist, hips, chest, neck, and left and right arms, quads and calves each log as their own entries. The left-right pairs feed a symmetry score: the percentage difference between your sides and which side is larger. A gap under half a centimeter counts as even, since a tape measure can't reliably detect less.
Symmetry sits on your progress page beside your training data, so you can see an imbalance next to the work that might address it.
A visual timeline, mapped to your numbers
Progress photos log against a pose (front, back, side and the rest of the catalog), a date and optional notes. A new photo can overlay the previous one in the same pose at adjustable opacity, so you can compare two shots directly. Photos sit on the same timeline as your weight and body fat entries.
How it reads the rest of the system
Your weigh-in trend drives Nutrition's calorie and macro targets. Training does not read your weight; it works from your logged sessions and volume. Health context (recovery, sleep and check-ins) sits beside the same trend when you are looking for the reason behind a plateau, and Upkeep's medication and condition records can explain a weight or measurement shift that training and nutrition data would not.
Frequently asked
- Do I need a smart scale to track body composition?
No. Manual weigh-ins, tape measurements, and the built-in Navy or Jackson-Pollock estimators work without any hardware. Withings scales sync automatically if you have one; InBody, DEXA, and other scan results are entered by hand. Every entry is tagged with where it came from.
- How accurate is the body fat estimator?
Navy and Jackson-Pollock estimate body fat from circumference or skinfold measurements, and MuscleBuddy labels them as estimates. A single reading can be several percentage points off; measured the same way each time, they are more useful for tracking a trend than for one number. This isn't medical advice; for a clinical body composition assessment, talk to a professional.
- What does the symmetry score compare?
Your logged left and right measurements for arms, quads and calves, as a percentage difference and which side reads larger. It updates when you log a new paired measurement.
- Does my weigh-in trend affect my training program?
It affects Nutrition: your calorie and macro targets move off your weigh-in trend. Training reads your logged sets and sessions, not your weight.
- Are my progress photos private?
Yes, by default. Health and body-composition data, progress photos included, is not shared anywhere unless you choose to. Sharing to the social feed is opt-in per post.
Start trending your own numbers
Log a weigh-in, a measurement or a photo and the trend starts from your first entry. Free: weigh-ins, measurements and the body-fat trend.