By Jeremey DuVall, M.S., CPT Men's Fitness
Measuring changes in body composition is one of the most effective means of evaluating your diet and workout routine. Lowering your body fat percentage is also crucial for getting that six-pack of abs and a chiseled physique. Unfortunately, finding an accurate way to track your changes in body composition can prove to be quite challenging. There are tons of different techniques, each with their pros and cons. We outline the most popular methods and identify which ones you should trust.
Note: For the best results, check your body composition every six to eight weeks to measure improvements and see progress.
The Gold Standards
DEXA (Dual-energy X-ray Absorptiometry) Scan
In a DEXA scan, X-ray technology is used to estimate lean tissue, bone, mineral, and fat across regions of the body with amazing accuracy. Not only will a DEXA scan let you know your precise body composition, but it will also break it down by body segment so you can see where you’re holding the most muscle and fat. X-ray technology makes DEXA scans extremely accurate but also harder to find. They can also be quite pricey. Check with your local physician to find one near you.
Since muscle is much denser than fat, body density can tell us a lot about body composition. With underwater weighing, the subject is submerged and their density is calculated to estimate body composition. The downside, you have to get wet, and you need to be submerged underwater which may not be comfortable for some. However, underwater weighing is an extremely accurate measure of body composition if you don’t mind going under.
Bod Pod (Whole Body Plethysmography)
As another method of measuring density, the Bod Pod measures air displacement to estimate body composition. The testing procedure is very similar to underwater weighing – minus the water. The main downside: Bod Pods are often hard to come by and they can be expensive to use. However, they can be an effective alternative to DEXA and are extremely accurate. Check your local sports medicine clinic to find one near you.
The Silver Standard
Skinfold measurements are done using calipers on several sites across the body. They take into account the amount of subcutaneous (directly under the skin) fat an individual has and use it to predict total body fat percentage. The most common variations are the 3-site and 7-site skinfold tests. Sites are slightly different between men and women, but the protocol remains the same. Skinfold measurements remain as a popular and widely used method of measuring changes in body composition since calipers are easy to use and found at almost any gym. For the best accuracy, avoid working out beforehand and have the same technician perform the measurements each time since each technique may be slightly different.
The Bronze Standard
Bioelectrical impedance analysis (BIA) scales are perhaps the most popular method of measuring body composition because they are the least expensive and most widely available. BIA technology applies an electrical current to the body and measures how quickly that current is conducted. Lean tissue and fat mass conduct electrical signals very differently so the scale can use conductance to estimate body composition. Although BIA is one of the most popular methods of measuring body composition the accuracy can widely vary depending on an individual’s hydration status and other factors. Use BIA in conjunction with other methods of measuring body composition to ensure accuracy and track results.