Tuesday, 28 May 2024

Near Infrared Interactance

Near Infrared Interactance

Near Infrared Interactance (NIR) is a method used to measure body composition by utilizing a computerized spectrophotometer. This technique involves the use of light absorption and reflection principles to determine body fat percentage accurately. NIR requires the use of a single, rapid scanning monochromator and a fiber optic probe.

How Near Infrared Interactance Works

During the NIR measurement, a low-energy beam of near-infrared light is directed into the biceps, penetrating the underlying tissue up to one centimeter deep. The light energy is either reflected, absorbed, or transmitted, depending on the scattering and absorption properties of the biceps. A detector within the device measures the intensity of the re-emitted light. By analyzing the wavelength shifts of the reflected beam and implementing a prediction equation, the percent body fat can be calculated.

Advantages of Near Infrared Interactance

NIR offers several advantages as a body composition measurement method. It is considered safe and utilizes portable and lightweight equipment. Additionally, it requires minimal training to operate effectively.

Limitations of Near Infrared Interactance

While NIR has its merits, there are a few limitations to consider. Firstly, this technique is still undergoing validation in humans and may not accurately predict body fat across a wide range of fat levels. It assumes that the fat distribution in the arm is proportional to the total body fat, which may not always be the case.

Tham Khảo Thêm:  Skinfold Caliper Guide

Similar Body Composition Tests

  • Dual-Energy X-Ray Absorptiometry (DEXA): This method enables the determination of body components, including non-fat soft tissue.
  • Total Body Potassium (TBK): TBK accurately determines the body’s total cell mass, which can be used to estimate fat-free or lean body mass. Combining TBK with Total Body Protein measurements allows for the determination of total organ and muscle mass.
  • Magnetic Resonance Imaging (MRI): MRI can provide accurate measurements of body tissue composition, including muscle, fat, and organs.
  • Total Body Electrical Conductivity (TOBEC): TOBEC can estimate lean body mass.
  • Computed Tomography (CT): CT produces high-quality images that can be processed to differentiate and measure the amounts of fat and lean body tissue.

Frequently Asked Questions (FAQs)

Q: Is Near Infrared Interactance a reliable method to measure body fat?
A: Near Infrared Interactance is still in the process of being validated in humans. While it may provide useful insights, its accuracy across various fat levels may vary.

Q: Can Near Infrared Interactance be used for body composition analysis in different body areas?
A: Near Infrared Interactance primarily focuses on the arm area, assuming proportionality to total body fat. It may not provide accurate results for other body regions.

Q: Can I perform Near Infrared Interactance measurements by myself?
A: Near Infrared Interactance requires a computerized spectrophotometer, which should be operated by trained professionals to ensure accurate and reliable results.


Near Infrared Interactance is a method that utilizes light absorption and reflection principles to measure body fat percentage. While it has advantages such as safety, portability, and ease of use, it still requires further validation in humans. It is recommended to consider alternative body composition tests for a comprehensive analysis.

Tham Khảo Thêm:  V Sit Reach Test

For more information about Near Infrared Interactance, visit Auralpressure.