I live and die by the numbers. They keep me honest about my progress and provide me with the knowledge I need to course correct as I tackle my strength and body composition goals. Here are the things I track on a regular basis:

  • Body composition
    • Bodyweight
    • Body fat percentage
    • Body fat (lbs) - Derived from above
    • Lean mass (lbs) - Derived from above
  • Macronutrient intake
  • Strength - Using Gravitus

In this post I'm going to focus on three tools I use to track body composition.

Omron HBF-306 Fat Loss Monitor

Omron HBF-306 Fat Loss Monitor

I've had this bad boy for 9 years and it's still going strong. Of the at-home tools I have, this one is the most accurate for assessing body fat percentage, although it's still off by a factor. Good enough for weekly use to monitor trends though.

For consistency of reading, it's best to measure first thing in the morning before you eat or drink anything.

Withings WS-50 Smart Body Analyzer

Withings WS-50 Smart Body Analyzer

This scale gets high props for ease of use and accuracy with measuring bodyweight. I got this particular model because I wanted a device that would send its data back to my phone wirelessly. It's a small nuance but it makes regularly weighing in and logging the result a more fun and painless process.

This device also measures body fat percentage. However, its readouts, while consistent, don't come close to being accurate. Thus, it's a useful second tool to monitor trends in body fat rather than exact measurements.



A DEXA scan provides a highly accurate assessment of your overall body composition, and even breaks that down for you for each region of your body. If you want to know your exact body fat percentage, a DEXA scan will give that to you.

I got mine at a local clinic for $40 out of pocket. The procedure is very simple: you lie down on the scanner bed and wait about 8 minutes while the arm above you scans your body from head to toe.

Given the cost and the fact that you have to make an appointment at a clinic, it probably makes sense to save the DEXA scans for larger milestones. I chose to do mine at the end of a 2 month cut.


Keep an eye on your body composition using these three tools, and monitor your strength using Gravitus. I like to use the Omron and Withings at least once a week (values fluctuate a bit, so daily seems excessive).

Numbers in hand, you'll be able to tweak your diet to maximize your gains and stay on the fast path to success.

Photo of Eric Wagner

Eric Wagner

- Gravitus profile

Eric is the Co-Founder & CEO of Gravitus. His passion for design, tech and setting PRs at the gym led him to start the company and create the app that we know and love.