Supervised Cycling Training Improves Erythrocyte Rheology in Individuals With Peripheral Arterial Disease

Chih-Chin Hsu; Yu-Ting Lin; Tieh-Cheng Fu; Shu-Chun Huang; Cheng-Hsien Lin; Jong-Shyan Wang

doi:10.3389/fphys.2021.792398

Supervised Cycling Training Improves Erythrocyte Rheology in Individuals With Peripheral Arterial Disease

Front Physiol. 2022 Jan 5:12:792398. doi: 10.3389/fphys.2021.792398. eCollection 2021.

Authors

Chih-Chin Hsu^{1

2}, Yu-Ting Lin³, Tieh-Cheng Fu¹, Shu-Chun Huang^{2

4

5}, Cheng-Hsien Lin³, Jong-Shyan Wang^{1

3

6}

Affiliations

¹ Department of Physical Medicine and Rehabilitation, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.
² School of Medicine, College of Medicine, Chang Gung University, Taoyuan City, Taiwan.
³ Healthy Aging Research Center, College of Medicine, Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan City, Taiwan.
⁴ Department of Physical Medicine and Rehabilitation, Linkou Chang Gung Memorial Hospital, Taoyuan City, Taiwan.
⁵ Department of Physical Medicine and Rehabilitation, New Taipei Municipal Tucheng Hospital, New Taipei City, Taiwan.
⁶ Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan City, Taiwan.

Abstract

Peripheral arterial disease (PAD) results in insufficient flow to lower extremities. Aerobic exercise provides health benefits for individuals with PAD, but basic science behind it is still debated. Twenty-one PAD patients aged about 70 years with female/male as 7/14 were recruited. Among them, 11 were randomized to have supervised cycling training (SCT) and 10 to receive general healthcare (GHC) as controls. SCT participants completed 36 sessions of SCT at the first ventilation threshold within 12 weeks and the controls received GHC for 12 weeks. Ankle-brachial index (ABI), 6-min walk test (6MWT), peak oxygen consumption ( $\dot{V}$ O_2peak), minute ventilation ( $\dot{V}$ _E), minute carbon dioxide production ( $\dot{V}$ CO₂), erythrocyte rheology, including the maximal elongation index (EI_max) and shear stress at 50% of maximal elongation (SS_1/2), and the Short Form-36 (SF-36) questionnaire for quality of life (QoL) were assessed before and 12 weeks after initial visit. SCT significantly decreased the SS_1/2 as well as SS_1/2 to EI_max ratio (SS_1/2/EI_max) and increased the erythrocyte osmolality in the hypertonic region as well as the area under EI-osmolality curve. The supervised exercise-induced improvement of erythrocyte deformability could contribute to the increased peripheral tissue O₂ delivery and was possibly related with increased $\dot{V}$ O_2peak. The physiological benefit was associated with significantly increased ABI, 6-min walking distance, cardiorespiratory fitness, and SF-36 score. However, no significant changes in aerobic capacity and erythrocyte rheological properties were observed after 12-week of GHC. In conclusion, SCT improves aerobic capacity by enhancing erythrocyte membrane deformability and consequently promotes QoL in PAD patients.

Keywords: aerobic exercise; erythrocyte deformability; erythrocyte osmotic fragility; hemorheology; peripheral arterial disease.