Carrie P. Earthman

Lateral stability during walking requires active control of the center of mass (COM) trajectory. In this short communication, we introduce lead- and trail-limb contributions to mediolateral COM acceleration during gait. These measures expand upon previous center of pressure (COP) contributions by accounting for limb- and phase-specific contributions, capturing the factors underlying previously proposed mechanisms of foot placement, ankle adjustments, and push-off. The COP contribution upon which our proposed measures are based, as well as an accompanying counter-rotation contribution, are quantified from a marker-based approach using motion-capture and force-plate-instrumented treadmill analyses. The purpose of this study was to validate a force-plate-only approach to quantifying lead-limb, trail-limb, and counter-rotation contributions to the lateral COM trajectory. Ten normal-weight, middle- to older-aged participants walked on an instrumented dual-belt treadmill at their preferred speed. Limb- and phase-specific contributions, as well as counter-rotation contributions, were calculated using marker-based and force-plate-only approaches. Agreement between the two approaches was assessed using intraclass correlations and Bland-Altman plots. Estimates for lead- and trail-limb contributions showed moderate to excellent agreement across both marker-based and force-plate-only approaches (ICC(2,1)=0.91 and 0.58, p<0.01, respectively). However, counter-rotation contributions within each phase showed poor between-approach agreement (ICC(2,1)<0.19). The limb- and phase-specific biomechanical influences on the lateral COM trajectory during gait can be measured using a force-plate-only approach in a valid manner.

Background: Patients with critical illness may present with disease‐related malnutrition upon intensive care unit (ICU) admission. They are at risk of development and progression of malnutrition over the disease trajectory because of inflammation, dysregulated metabolism, and challenges with feeding.Methods: The Global Leadership Initiative on Malnutrition (GLIM) convened a panel of 36 clinical nutrition experts to develop consensus‐based guidance statements addressing the diagnosis of malnutrition during critical illness using a modified Delphi approach with a requirement of ≥75% agreement.Results: (1) To identify pre‐existing malnutrition, we suggest evaluation within 48 h of ICU admission when feasible (100% agreement) or within 4 days (94% agreement). (2) To identify the development and progression of malnutrition, we suggest re‐evaluation of all patients every 7–10 days (97% agreement). (3) To identify progressive loss of muscle mass, we suggest evaluation of muscle mass as soon as feasible (92% agreement) and again after 7–10 days (89% agreement). (4) To identify the development and progression of malnutrition before and after ICU discharge, we suggest re‐evaluating nutrition status before ICU discharge and during clinical visits that follow (100% agreement).Conclusion: Research using consistent etiologic and phenotypic variables offers great potential to assess the efficacy of nutrition interventions for critically ill patients with malnutrition. Assessment of these variables during and beyond the ICU stay will clarify the trajectory of malnutrition and enable exploration of impactful treatment modalities at each juncture. GLIM offers a diagnostic approach that can be used to identify malnutrition in critically ill patients.

Background Bioelectrical impedance analysis (BIA) is a technique widely used for estimating body composition and health-related parameters. The technology is relatively simple, quick, and non-invasive, and is currently used globally in diverse settings, including private clinicians’ offices, sports and health clubs, and hospitals, and across a spectrum of age, body weight, and disease states. BIA parameters can be used to estimate body composition (fat, fat-free mass, total-body water and its compartments). Moreover, raw measurements including resistance, reactance, phase angle, and impedance vector length can also be used to track health-related markers, including hydration and malnutrition, and disease-prognostic, athletic and general health status. Body composition shows profound variability in association with age, sex, race and ethnicity, geographic ancestry, lifestyle, and health status. To advance understanding of this variability, we propose to develop a large and diverse multi-country dataset of BIA raw measures and derived body components. The aim of this paper is to describe the ‘BIA International Database’ project and encourage researchers to join the consortium. Methods The Exercise and Health Laboratory of the Faculty of Human Kinetics, University of Lisbon has agreed to host the database using an online portal. At present, the database contains 277,922 measures from individuals ranging from 11 months to 102 years, along with additional data on these participants. Conclusion The BIA International Database represents a key resource for research on body composition.