Association Between 6-Minute Walk Test Distance and Objective Variables of Functional Capacity After Exercise Training in Elderly Heart Failure Patients With Preserved Ejection Fraction: A Randomized Exercise Trial.
To evaluate the change in the 6-minute walk test (6-MWT) distance relative to changes in key functional capacity measures after 16 weeks of exercise training in older patients (≥65y) who have heart failure with preserved ejection fraction (HFpEF).



Prospective, randomized, single-blinded (by researchers to patient group) comparison of 2 groups of HFpEF patients.



Hospital and clinic records; ambulatory outpatients.



Participants (N=47) randomly assigned to an attention control (AC) (n=24) or exercise training (ET) (n=23) group.



The ET group performed cycling and walking at 50% to 70% of peak oxygen uptake (V˙o2peak) intensity (3d/wk, 60min each session).



V˙o2peak, ventilatory threshold (VT), and 6-MWT distance were measured at baseline and after the 16-week study period.



At follow-up, the 6-MWT distance was higher than at the baseline in both the ET (11%, P=.005) and AC (9%, P=.004) groups. In contrast, V˙o2peak and VT values increased in the ET group (19% and 11%, respectively; P=.001), but decreased in the AC group at follow-up (2% and 0%, respectively). The change in V˙o2peak versus 6-MWT distance after training was also not significantly correlated in the AC group (r=.01, P=.95) or in the ET group (r=.13, P=.57). The change in 6-MWT distance and VT (an objective submaximal exercise measure) was also not significantly correlated in the AC group (r=.08, P=.74) or in the ET group (r=.16, P=.50).



The results of this study challenge the validity of using the 6-MWT as a serial measure of exercise tolerance in elderly HFpEF patients and suggest that submaximal and peak exercise should be determined objectively by VT and V˙o2peak in this patient population.
Department of Physical Education and Sport, Faculty of Education and Sport-Physical Activity and Sport Section, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz, Araba/Álava, Basque Country, Spain. Electronic address: sara.maldonado@ehu.eus.
Sara
S
Maldonado-Martín
Department of Health and Exercise Science, Wake Forest School of Medicine, Winston-Salem, NC.
Peter H
PH
Brubaker
Sections on Cardiovascular Medicine and Geriatrics, Department of Internal Medicine, Wake Forest University, Winston-Salem, NC.
Joel
J
Eggebeen
Sections on Cardiovascular Medicine and Geriatrics, Department of Internal Medicine, Wake Forest University, Winston-Salem, NC.
Kathryn P
KP
Stewart
Department of Health and Exercise Science, Wake Forest School of Medicine, Winston-Salem, NC.
Dalane W
DW
Kitzman
D005081:Exercise Therapy / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006333:Heart Failure / Q000534:rehabilitation*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D011446:Prospective Studies; D016037:Single-Blind Method; D000070857:Walk Test
Exercise test; Oxygen consumption; Physical fitness; Rehabilitation
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