Why Body Composition?
Most of our BODYSIM clients want to reduce their body fat percentage, either through increasing lean mass, losing fat, or a combination of both. However, a lot of us wonder what our ideal body fat percentage should be. Of course, it depends on whether your goals are focused more on long-term health, longevity, and/or aesthetics. A “healthy” body fat %, depending on age, would range somewhere between 14%-30% for women and 8-25% for men. A common–though stretch–aesthetic goal for men is 12-14% body fat, and a similar goal for women would be 20-23% body fat.
Many of our users have found that their best approach to a body fat percentage change is actually through a focus on building lean mass through diet and resistance training. It’s incredible the changes many body types can see just in adding total weight and lean mass without adding fat (reducing their body fat % as a result!)
Understanding Where You Are
We recommend starting by building an assessment of current state and thinking about what is attainable, given your gender and frame size.
Unless they’re already using DEXA to follow body composition, our users are unequivocally surprised by their DEXA-measured body fat. Some studies have shown the offset between DEXA body fat and BIA body fat to be approximately 3.1-7.5 percentage points, but in practice, we’ve found that difference to be as much as 10 percentage points for both lean men and women, and this Spanish study of professional soccer players mirrors what we have seen1.
Once you know where your lean mass and body fat is based on DEXA, BODYSIM creates a personalized simulation to estimate your daily values. Your quarterly DEXA measurements will keep this correction up to date, and you can track the contribution of muscle hydration, GI contents, and glycogen stores to your scale weight. In the screenshot below, you can see this user’s measured and simulated body fat over time, along with corrections to values from two different brands of BIA scale.
The next two screenshots show how the model takes hydration error and glycogen into account when calculating body composition. The chart called “Body Composition Change Breakdown” will show the additional scale weight, for example, from eating additional carbs that will be stored as glycogen.
Tracking Daily Data
We’ve chosen to work with the Withings Body Scan scale because it’s the best available scale on the market that will give you a daily body fat measurement. It’s the only home scale that is octopolar, which means it assesses both sides of the body with bioelectrical impedance. While the daily values might not track with your true values (you can see how this looks over time in the screenshots above), we have found it to be directionally informative to an extent that we can use for triangulation of your metabolism.
Once you’ve been tracking macros, exercise, and body comp with the scale for about a week, you’ll be able to assess where you can go with lean mass. You’ll get a score for Training Age, which is a metric of where you are on a personal scale of muscle mass potential. In addition to your baseline body composition from DEXA and the daily values from the BIA scale, we’ve integrated with Prism Labs 3D2 body scanner to get automatic measurements by muscle group, so you can choose areas that might be underdeveloped to focus on.
So What? Take Control of Your Body Comp
The real power of your BODYSIM digital twin is how you can start to leverage it to forecast forward, with questions like:
- What will happen if I step up my protein consumption?
- What will happen if I add a few hundred calories per day for the next month?
Let your BODYSIM tell you what is possible with your body composition and make change happen!