Eccentric Cycling: A Promising Modality for Patients with Chronic Heart Failure.
Chronic heart failure (CHF) is characterized by dyspnea and poor exercise tolerance, which decreases aerobic capacity (V˙O2peak), a measure strongly correlated with quality of life and mortality. In healthy populations, eccentric (ECC) cycling can be performed at a lower oxygen demand for matched workload, compared with concentric (CON) cycling, but few studies have previously investigated ECC cycling in CHF. We hypothesized that, when matched for external workload (W), an ECC cycling bout would be performed at a lower cardiorespiratory load (V˙O2) than CON in patients with CHF.



Eleven CHF patients (10 males) with impaired left ventricular systolic function (ejection fraction 31% ± 12%) completed a CON V˙O2peak test, with the subsequent ECC and CON protocols set at 70% of individual maximal CON power (W). Oxygen consumption (V˙O2), RER, minute ventilation (V˙E), HR, and rate pressure product were compared between conditions.



ECC was performed at a lower V˙O2 (12.3 ± 1.3 vs 14.1 ± 0.8 mL·kg·min, P = 0.01), RER (0.92 ± 0.02 vs 0.96 ± 0.01, P = 0.01), and V˙E (36.5 ± 4.4 vs 40.2 ± 2.0 L·min, P = 0.04) in comparison with CON, despite both conditions being performed at matched workloads. HR (101 ± 5 vs 96 ± 1 bpm, P = 0.06) and rate pressure product (13,539 ± 788 vs 11,911 ± 227 bpm·mm Hg, P = 0.15) were not significantly different between conditions.



When matched for external workload, ECC cycling can be performed with a lower oxygen demand than CON in patients with CHF. Eccentric cycling is a promising modality for cardiac rehabilitation in severely deconditioned patients with CHF.
1School of Sport Science, Exercise and Health, The University of Western Australia, Crawley, AUSTRALIA; 2Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, UNITED KINGDOM; 3Principal Research Fellow, National Health and Medical Research Council, AUSTRALIA; 4School of Physiotherapy and Exercise Science, Curtin University, Perth, AUSTRALIA; 5Allied Health Department, Fiona Stanley Hospital, Perth, AUSTRALIA; 6Centre for Exercise and Sports Science Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, AUSTRALIA; and 7Advanced Heart Failure and Cardiac Transplantation Unit, Fiona Stanley Hospital, Perth, AUSTRALIA.
Lauren C
LC
Chasland
Daniel J
DJ
Green
Andrew J
AJ
Maiorana
Kazunori
K
Nosaka
Andrew
A
Haynes
Lawrence G
LG
Dembo
Louise H
LH
Naylor
D001642:Bicycling / Q000502:physiology*; D001794:Blood Pressure; D002908:Chronic Disease; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006333:Heart Failure / Q000503:physiopathology* / Q000534:rehabilitation; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D063806:Myalgia / Q000209:etiology; D010101:Oxygen Consumption