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Updated: May 8, 2026

Measuring Deformability and Red Cell Heterogeneity in Blood by Ektacytometry
Published on: January 12, 2018
Influence of endurance training and marathon running on red cell deformability in HIV patients
Basit Ahmad1, Katharina Glufke1, Marijke Grau1
1Department of Molecular and Cellular Sport Medicine, Institute for Cardiovascular Research and Sport Medicine, German Sport University Cologne, Cologne, Germany.
Purpose:
This investigation assessed whether endurance training altered the red cell deformability (RCD) of male HIV patients.
Methods:
Eight subjects (38 ± 9 years, BMI 23 ± 3.6 kg/m², highly active antiretroviral therapy) trained for a marathon run for the duration of one year. Each subject underwent an acute exercise test on a treadmill at the beginning of this study (baseline) and after four months of training. Blood samples were taken at rest (T0) and at the end (T1) of each exercise test, as well as before (T0) and after the marathon run (T1). RCD was measured using the Laser Assisted Optical Rotational Cell Analyzer (LORCA), the maximal elongation index (EImax) and shear stress at half maximal deformation (SS ½ were determined using the Lineweaver Burke model.
Results:
No changes were observed in RCD and SS ½ between T0 and T1 in all measurements. EImax significantly increased between T0 baseline and T0 after four months of training (P < 0.05). Measurements prior to the marathon run revealed significantly decreased EImax and SS ½ values (P < 0.05).
Conclusions:
The intensity of training in pathophysiological diseases like HIV is dependent for the alterations in RCD and possible improvements in microcirculation.
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