Int J Sports Med 2002; 23(5): 361-366
DOI: 10.1055/s-2002-33145
Training and Testing
© Georg Thieme Verlag Stuttgart · New York

Bioelectrical Impedance to Estimate Changes in Hydration Status

C.  O'Brien1 , A.  J.  Young1 , M.  N.  Sawka1
  • 1U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
Further Information

Publication History



Accepted after revision: 3. November 2001

Publication Date:
16 August 2002 (online)

Preview

Abstract

Bioelectrical impedance analysis (BIA) has been suggested as a simple, rapid method to assess changes in hydration status. BIA measures the electrical impedance to a low amperage current that is affected by both water and electrolyte content of the body. While BIA can reliably estimate total body water and body density in euhydrated individuals under standardized clinical conditions, changes in fluid and electrolyte content can independently alter bioimpedance measurements. Because hydration changes typically involve concomitant changes in fluid and electrolyte content, the interpretation of a change in bioimpedance will often be confounded. This paper examines the assumptions underlying estimations of total body water from BIA and addresses the factors known to influence bioimpedance independently from actual change in total body water. The results indicate that current BIA methodology may not provide valid estimates of total body water when hydration state is altered.

References

C. O'Brien

Thermal and Mountain Medicine Division · U.S. Army Research Institute of Environmental Medicine

Natick, MA 01760-5007 · USA ·

Phone: +1 508 (233) 5973

Fax: +1 508 (233) 5298

Email: catherine.o'brien@na.amedd.army.mil