Post-Exercise Neurovascular Control in Chronic Heart Failure Patients.
It remains unknown whether or not a reduction in muscle sympathetic nerve activity in heart failure patients is associated over time with the effects of long- or short-term repeated exercise. 10 chronic heart failure patients, age 49±3 years old, functional class I-III NYHA, ejection fraction <40% were randomly submitted to either an acute bout of moderate continuous exercise OR high-intensity interval exercise. Muscle sympathetic nerve activity (microneurography) and forearm blood flow (venous occlusion plethysmography) were evaluated pre- and post-exercise sessions. The moderate exercise consisted of cycle exercise at an intensity corresponding to anaerobic threshold. The interval exercise consisted of a 2-min cycle exercise at intensity corresponding to anaerobic threshold, followed by a 1-min exercise set at respiratory compensation point. Exercise capacity was evaluated by cardiopulmonary exercise test. The caloric expenditure in both sessions was 100 kcal. Baseline muscle sympathetic nerve activity and forearm blood flow levels were not different between sessions. Moderate or high-intensity exercise caused no significant changes in muscle sympathetic nerve activity and forearm blood flow. These findings suggest that the reduction in muscle sympathetic nerve activity and the increase in forearm blood flow provoked by exercise training in chronic heart failure patients are due to cumulative effects over time.
Heart Institute (InCor), Medical School of University of Sao Paulo, Cardiovascular Rehabilitation and Exercise Physiology Unit, Sao Paulo, Brazil.
T S
TS
Nobre
Heart Institute (InCor), Medical School of University of Sao Paulo, Cardiovascular Rehabilitation and Exercise Physiology Unit, Sao Paulo, Brazil.
R V
RV
Groehs
Heart Institute (InCor), Medical School of University of Sao Paulo, Cardiovascular Rehabilitation and Exercise Physiology Unit, Sao Paulo, Brazil.
L F
LF
Azevedo
Heart Institute (InCor), Medical School of University of Sao Paulo, Cardiovascular Rehabilitation and Exercise Physiology Unit, Sao Paulo, Brazil.
L M
LM
Antunes-Correa
Unit of Cardiovascular Investigation and Exercise Physiology,Faculty of Physical Education, Federal University of Juiz de Fora, Minas Gerais, Brazil.
D G
DG
Martinez
Heart Institute (InCor), Medical School of University of Sao Paulo, Cardiovascular Rehabilitation and Exercise Physiology Unit, Sao Paulo, Brazil.
M J N N
MJ
Alves
Heart Institute (InCor), Medical School of University of Sao Paulo, Cardiovascular Rehabilitation and Exercise Physiology Unit, Sao Paulo, Brazil.
C E
CE
Negrao
D002908:Chronic Disease; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D005542:Forearm / Q000098:blood supply; D006333:Heart Failure / Q000503:physiopathology*; D000072696:High-Intensity Interval Training; D006801:Humans; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000294:innervation*; D010991:Plethysmography; D012039:Regional Blood Flow; D013564:Sympathetic Nervous System / Q000503:physiopathology*