PMID- 12365353
OWN - NLM
STAT- MEDLINE
DCOM- 20030403
LR  - 20191106
IS  - 0018-442X (Print)
IS  - 0018-442X (Linking)
VI  - 53
IP  - 1
DP  - 2002
TI  - Influence of various factors on the measurement of multifrequency bioimpedance.
PG  - 1-16
AB  - Body impedance values at various frequencies (from 1 to 100 kHz) were determined 
      in 104 subjects on seven separate days over a two-week period. The variability of 
      body impedance in different measurement conditions was studied. In particular, 
      the effects of the electrode locations, the ingestion of some substances (sugar, 
      alcohol, mineral salts), body spatial geometry, the time spent in the supine 
      position and the menstrual cycle were assessed. Under standardized conditions (in 
      the morning, in the fasting state, with an empty bladder and with the body in a 
      standardised spatial position), the within-subject day-to-day variability was 
      3-14 Ohms. Under different experimental conditions, the within-subject 
      variability was generally much higher. This was particularly evident for female 
      subjects. We observed significant mean variations in relation to the different 
      experimental factors introduced one at a time, with the exception of the 
      menstrual cycle. For example, half an hour after the intake of various 
      substances, body impedance had generally increased by 6-17 Ohms in comparison 
      with values in the fasting state. Changes in body impedance during the menstrual 
      cycle, however, were small and never statistically significant. The impedance 
      variations obviously caused significant changes in estimated parameters of body 
      composition. It is concluded that controlled conditions and standardization of 
      multifrequency bioimpedance analysis (MBIA) methods are indispensable for the 
      application of this technique.
FAU - Gualdi-Russo, E
AU  - Gualdi-Russo E
AD  - Dipartimento Biologia Evoluzionistica Sperimentale, Via Selmi n.3, I-40126 
      Bologna. gualdi@alma.unibo.it
FAU - Toselli, S
AU  - Toselli S
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Germany
TA  - Homo
JT  - Homo : internationale Zeitschrift fur die vergleichende Forschung am Menschen
JID - 0374655
SB  - IM
MH  - Adult
MH  - *Body Composition
MH  - *Eating
MH  - Electric Impedance
MH  - Female
MH  - Humans
MH  - Male
MH  - Menstruation
MH  - *Periodicity
MH  - Reference Values
MH  - Reproducibility of Results
MH  - Sex Factors
EDAT- 2002/10/09 04:00
MHDA- 2003/04/04 05:00
CRDT- 2002/10/09 04:00
PHST- 2002/10/09 04:00 [pubmed]
PHST- 2003/04/04 05:00 [medline]
PHST- 2002/10/09 04:00 [entrez]
AID - S0018-442X(04)70023-2 [pii]
AID - 10.1078/0018-442x-00035 [doi]
PST - ppublish
SO  - Homo. 2002;53(1):1-16. doi: 10.1078/0018-442x-00035.