PP096 - DIFFERENCES IN BODY COMPOSITION OUTCOMES USING SF-BIOELECTRICAL IMPEDANCE ANALYSIS WITH EIGHT ALTERNATIVE FOOT-LEG ELECTRODE PLACEMENTS VERSUS THE STANDARD PROTOCOL

PP096

DIFFERENCES IN BODY COMPOSITION OUTCOMES USING SF-BIOELECTRICAL IMPEDANCE ANALYSIS WITH EIGHT ALTERNATIVE FOOT-LEG ELECTRODE PLACEMENTS VERSUS THE STANDARD PROTOCOL

G. E. C. Slager^1,2,*, G. H. Steggink², E. M. Sjouke², A. D. Bieler², M. J. Sealy^1,3

¹Research Group Healthy Ageing, Allied Health Care and Nursing, ²Department of Physiotherapy, Hanze University of Applied Sciences, Groningen, ³Department of Gastroenterology and Hepatology, Dietetics, Radboud University Medical Center, Nijmegen, Netherlands

Rationale: Bioelectrical impedance analysis (BIA) uses two electrode pairs placed at standard positions on the right hand and foot-leg (pA), which may be unsuitable for patients with fragile skin, wounds or amputations. We studied differences in body composition outcomes at eight alternative foot–leg electrode placements compared with the standard position pA.

Methods: 50 kHz BIA was performed using the Bodystat-500. Eight alternative foot electrode placements were compared with pA, defined as dorsal foot and ventral placement between the malleoli. The distal electrode (1) was relocated to the plantar surface at the forefoot (p1B), midfoot (p1C), heel (p1D), and posterior heel (p1I). The proximal electrode (2) was placed posterior to the lateral (p2E) and medial malleoli (p2G), more proximally on the lower leg (p2F), and on the posterior heel (p2H). Differences in fat mass (ΔFM) and fat-free mass (ΔFFM) were calculated using Kyle’s formula. Intraclass correlation coefficients (ICCs) and median (IQR) differences (p <0.05*) were assessed.Bovenkant formulier

Results: 81 healthy Caucasian participants were included: median age 22 years [21-24]; mean BMI 22.8 ± 2.3 kg/m². Electrode positions showed minimal median differences at p1B, p1C and p1D in ∆FFM and ∆FM: -0.1 [-0.2; 0.0]* to  0.2 [0.1- 0.3]*; moderate differences at p2G: 0.2 [0.0; 0.6]*, p2E: 0.3 [-0.1; 0.6]*;  p1I: 0.4 [0.3; 0.6]*; and large, clinical relevant differences at p2H: -0.7 [-1.1; -0.5]* and p2F: 1.3 [1.0; 1.7]*. ICCs were high for all measurements (0.98-1.00).

Conclusion: Plantar placement of the distal electrode at the forefoot, midfoot, or heel is a valid alternative to the standard protocol. Proximal electrode repositioning is only recommended posterior to the medial or lateral malleolus when standard placement is not feasible.

Disclosure of Interest: None declared