Residual volume (RV) is the volume of air remaining in the respiratory passageways after a maximal expiration. RV must be measured or estimated to correct for the buoyancy of air in order to calculate body density and fat percentage from underwater weighing.
The EXERTECH® RV system provides accurate and reliable measurements in seconds by means of a simple procedure that has been validated against the original (Wilmore, 1969) method.
A measured volume of oxygen is dispensed into a rubber bag and the dilution of the oxygen by respiratory nitrogen during rebreathing is monitored by means of a high speed electronic nitrogen gas analyzer.
Computer software calculates RV from the oxygen volume and the change in N2 fractions.
Customer Feedback about the RV measurement system:
"It's a great system. Easy to use." Dr. Jody Clasey – Univ. of KY.
"We are loving our system - no problems." Dr. David Fields – Univ. of OK.
"The system is working well." Dr. Art Weltman – Univ. of VA.
Residual Volume Measurement - Literature Citations
Biaggi, R.R., M.W. Vollman, M.A. Nies, C.E. Brener, P.J. Flakoll, D.K. Levenhagen, M. Sun, Z. Karabulut, and K.Y. Chen. Comparison of air-displacement plethysmography with hydrostatic weighing and bioelectrical impedance analysis for the assessment of body composition in healthy adults. Am. J. Clin. Nutr. 69: 898-903, 1999.
Johnson, B.M., W.A. Floyd, J.C. Tesch, P.K. Wilson, and D.M. O'Brien. Validation of a modified closed circuit, oxygen dilution RV method. Med. Sci. Sports and Exer. 26(5) supplement, Abstract 1168, 1994.
