How Bodybuilders Measure Arm Size

Whether you are a professional bodybuilder or just starting a weightlifting program, increases in the size of your arms may be taken as a sign of success. While measuring your arm size may seem straightforward, different methods may result in inaccurate measurements. By following the methods used by professional bodybuilders, you can arrive at an arm measurement that accurately reflects your bodybuilding progress.

Bodybuilders have developed accurate ways to measure arm size. (Image: Marcus0711/iStock/Getty Images)

Gullick Tape

Strength training coach Charles Poliquin recommends on the T Nation website that you have your arms professionally measured before beginning an arm development program. To ensure that your arms are properly measured, kinesiologists use a machine known as a Gullick tape. This flexible steel tape is wrapped around the largest part of your arm and pulled tight, measuring both your arm's circumference and the amount of tension on the tape. This tension measurement helps to ensure that you are not distorting your arm measurement by pulling the tape too tight, thus helping you to measure your arm in the same way each time.

How to Measure Your Arm

Whether you are using a measuring tape or a Gullick tape, Poliquin recommends that you measure your arm by starting with your arm parallel to the ground. In this position, pull your hand toward your shoulder until your elbow is pointing directly in front of you. Wrap the tape measure or Gullick tape around the largest part of your arm, typically around the peak of your bicep and tricep muscles. To ensure an accurate measurement, Poliquin says that you position the circle formed by the tape so that it is perpendicular to the ground.

General Considerations

Poliquin urges you to measure your arm in an unflexed state. Due to the temporary effects of exercise and hydration on muscle size, he suggests that you avoid measuring your arms after a workout. In addition, he recommends you always measure your arms at the same time of day. Whether you are using a Gullick tape or traditional cloth measuring tape, you should avoid excessively pulling on the tape to avoid distorting your true arm measurement.

Tracking Progress

While you may wish to measure your arms as often as possible, Poliquin recommends you only perform measurements 48 hours after making increases in the amount of weight that you lift. And if you are having your arms professionally measured, visit a kinesiologist every six weeks. Whether performing your own measurements or having them done professionally, keep a diary with exact measurements to help track your progress.