BODYSIM is an app-based system that learns your unique metabolism and physiology, and continues to reveal your body composition by fusing a variety of data and sensors using a scientific model of metabolism and hypertrophy. The BODYSIM system covers every major element that supports your physical health and progress.

BODYSIM translates the best academic research into software and a system you can use to achieve your goals. The heart of that software is a scientific simulation model of human metabolism and physiology. Building this model was no easy task—we believe it to be the first time all the pieces of the diet, nutrition, exercise, physiology and metabolism puzzle have been integrated into a cohesive whole.

The creators of BODYSIM have been translating academic research into software for decades. Our team of biologists, mathematicians and computer scientists are experts in the kind of translational research it takes to collect, piece together, synthesize and extend academic research in complex domains. We’ve successfully translated models into software for the Human Genome, cancer genetics, molecular plant breeding, high-frequency trading, consumer buying behavior, battery electrochemistry and more.

The BODYSIM subscription service is uniquely powered by a mathematical model of human metabolism and physiology, combined with sensor fusion, to help you achieve your body composition goals. This subscription includes:

• A comprehensive starter package that includes:
  • BIA body composition scale (Withings® Body Scan)
  • Kitchen food scale (Escali®)
  • Baseline DEXA scan (at a DEXAFit® location near you)
  • Stainless steel insulated BlenderBottle® Strada™ Sleek
• Food logging iOS phone application
• Interactive composition goal and diet and exercise plan builder
• Continuous progress monitoring and estimation of your metabolism, physiology and sensor biases
• Sophisticated body composition forecasting and what-if diet and exercise scenario planning toward your goal
• Monthly at-home blood testing of select diet and exercise biomarkers
• Follow-up DEXA scans every 3 months
• White-glove community and email support

At this time, there is no free version of BODYSIM.

Some future BODYSIM features, such as AR portion size estimation, may require rear-facing LiDAR, such as those currently only available on the Pro and Pro Max models of iPhone 12 and newer.

BODYSIM is available only on Apple iOS devices. There are currently no plans for an Android version.

For BODYSIM to work as designed, you need to feed the model with specific measurements and data points. To get the full BODYSIM experience, you will need to:

• Describe your frame with initial measurements, like height and wrist circumference.
• Get a DEXA scan at a DEXAFit location to baseline your starting muscle, bone and fat composition.
• Complete our baseline at-home blood test to ensure select hormones, diet markers and vitamins/minerals aren’t holding you back.
• Track your daily macros in the BODYSIM app’s food journal.
• Weigh yourself most days on the provided WiFi body composition scale.
• Let the BODYSIM team help you set a body composition goal, such as to lose 5 pounds of fat and gain 10 pounds of muscle over 4 months.
• Let us help you define a diet and exercise plan describing your daily calories, macros, resistance training and cardio.
• Wear a fitness tracker.

An excellent starting benchmark is the foundation to monitoring progress. DEXA scans are the gold standard method to assess body composition by partitioning muscle, bone and fat mass.

Other methods do not work. Even the best “calculators” (we call them anthropometric estimations) can be hugely off for some people—enough to imply a difference in estimated BMR greater than the entire caloric deficit or surplus necessary to reach their goal. Machine learning methods based solely on vision, such as those that take 3D scans of your body in an office, on your phone or even in a special suit, claim accuracy on par with DEXA but do not in fact deliver.

We have seen body fat percentage errors of 50%(!) versus DEXA from even the leading machine learning vision-based app. BIA or body composition scales, home versions and more sophisticated scales you might find at the gym or your doctor’s office similarly may report correct trends but are notoriously inaccurate; we’ve seen consistent, repeated body fat percentage errors of 75%(!!) versus DEXA even on the best home octopolar, multifrequency BIA scale.

Our blood panel includes unique “off-label” measures of your hormonal sufficiency, key vitamin and mineral sufficiency, a marker of sufficient resistance training and supplementation, markers for sufficient/excess macro consumption, and liver and kidney controls; along with our custom fitness focused reference ranges and literature links {Free Testosterone, Total Testosterone, Albumin, SHBG, E2, Free T3, Creatinine, Cystatin C, AST, GGT, 25-(OH) Vitamin D, Ferritin, Prolactin, HOMO-IR, Insulin, Glucose, BUN, A1C, Total Cholesterol. Tests in the State of New York may differ due to regulations.}

Setting a realistic goal can be hard for two major reasons. First, it’s difficult to set a goal that’s personalized to all the factors of your physiology and metabolism–what’s right for someone else might not be right for your body. Second, there are many different paths to achieving that realistic goal with different levels of pain. Sure, you could lift for 4 hours a day or go on a 1,000-calorie crash diet to get there fast. But is it worth it for you? How high a price are you willing to pay?

BODYSIM learns your unique metabolism and physiology so you can set goals that are realistic for your body. It allows you to simulate how different diet and exercise plans would allow you to reach your goals, so you can pick and dial in a plan that works for your body and your life.

Your body composition—and improving it—is at the heart of BODYSIM. When we refer to body composition, we mean the percentage of muscle, fat and bone that makes up your body weight.

BODYSIM implements the most sophisticated energy balance estimation of any app on the market. BODYSIM’s estimate of your energy balance accounts for large and important sources of information and error, including:

• Scale weight, including their bias and noise
• Scale body fat, including their bias and noise
• Fitness trackers, including their bias and noise
• Your anthropometrics (frame size, etc.)
• Your food logging data
• Your DEXA scans

Because BODYSIM implements a detailed scientific model of human metabolism and physiology, it can triangulate the truth about your basal metabolic rate (BMR) and energy balance by considering how all of these noisy observations must come together and evolve in your body through time. Building muscle requires a certain amount of protein, extra energy and resistance training.

Follow your tracker manufacturer’s instructions to sync with Apple Health:

• Instructions for Garmin
• Instructions for Whoop
• Instructions for Oura
• Instructions for Withings

BODYSIM integrates with any fitness tracker that supports Apple Health. This includes Apple Watch, Garmin watches (Venu, Forerunner, Instinct, Epix and Fenix) and trackers (including Vivosmart), Whoop, Oura and Withings watches.

Some BODYSIM users have had difficulty getting Oura rings to track workout heart rates, presumably due to the lack of half ring sizes. We do not recommend purchasing a new Oura ring for BODYSIM unless you already know it is capable of tracking workout heart rates on you. If your Oura ring does track your workout heart rate, it will work with BODYSIM.

BODYSIM does NOT support Fitbit or Google Pixel trackers or watches, as these devices do not integrate with Apple Health.

Strive for food logging accuracy by following these strategies:

• Use the label scanner. To achieve the highest accuracy, always include the big 4: calories, protein, fat and carbs.
• Think big. You don’t need to log items with little nutritional value, like water, spices and supplements. Always log high-calorie items, like oil, butter and sugar, no matter the amount.
• Log by weight, not volume. Use your included smart-scale to accurately log meals by weight. Logging by volume isn’t ideal, but it’s better than guessing; you can also select a close substitute/proxy food.
• Use group and recipe functions. Unlike other apps, BODYSIM “groups” can be used like repeated meals or recipes containing other foods and can be nested: a supper group of a steak, a slice of a cornbread recipe-group, and a tablespoon of a pan sauce recipe -group.
• Do your best with the unknown. Especially at smaller restaurants, you’ll have to make two big guesses: portions in volume units and components of recipes. Use our guide for portions and remember to include butter, nuts, cheese and sugary ingredients.
• Find online sources. Many chain restaurants, grocery stores and food manufacturers put nutritional info on their website.

We recommend that you track your macros every day. With a stretch goal in mind, it can be difficult to stay on plan without a comprehensive support system like our app’s food journal. However, sometimes it’s just not practical. When you cannot complete a log, we encourage you to remember these tips:

• Don’t skip logging on exceptional or outlier days. BODYSIM will fill in your skipped days with your typical habits. If you tend to not log on days that are much higher or lower in calories, protein, fat or carbs than usual, you will create a bias BODYSIM cannot remove. Always log exceptional days unless they are very infrequent, like a holiday potluck.
• Never log a partial day. BODYSIM will assume that your partial day was actually a full day and you ate very little. If you cannot log a full day, delete all foods from that day entirely.
• Keep your missed days sporadic. It’s OK to not log a typical day here and there, but avoid runs of successive days without logging. If you have a weeklong work trip or a vacation, try to log at least a few of those days.

BODYSIM is constantly learning where you are and what must be true about your unique metabolism, physiology and habits to have gotten you here. If you don’t hit your goals on schedule, BODYSIM learns what portion of that gap was related to your diet or exercise gap to plan and what portion represents a new understanding of your potential metabolism. BODYSIM then uses this understanding to help you get a new, more accurate plan tailored to you.

As a member of the BODYSIM community and part of your subscription, we provide you with tools and guidance you need to be successful. (You must provide the drive to reach your goals, though.) Your subscription includes prepaid DEXA scans at the DEXAFit franchise location closest to you, a Withings body composition scale, a kitchen smart-scale, at-home blood tests mailed to your home and more.

A fitness tracker is strongly recommended, and BODYSIM supports all trackers that integrate with Apple Health.

BODYSIM is an informational tool and is not designed to diagnose or treat any disease. BODYSIM results are for informational purposes only and are not intended to replace or substitute for a physician’s medical judgment or to be relied upon as a professional opinion. No communication from BODYSIM is intended to be or should be construed as medical advice. Always consult your physician or medical professional for any medical advice, decision or actions regarding your health care, or when changing your workouts, supplements or diet.

To learn more about how BODYSIM can help you find your peak potential, contact us at support@bodysim.com.