Exercise for Cardiovascular Disease Prevention and Treatment From Molecular to Clinical, Part 1

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Resistance ET, also called as strength training, is being increasingly prescribed

to patients with cardiovascular complications, from hypertensive to heart failure

patients. Indeed, several evidence have been demonstrating that resistance ET can

participate in conjunction with aerobic ET, or even alone, in the control of blood

pressure values in hypertensive patients [ 41 , 42 ]. Regarding MI, data from basic

research are still very limited.

In front of this lack in the literature, Grans et  al. [ 19 ] subjected MI-rats to

12  weeks of low to moderate (40–60% of the maximum strength) resistance ET 

program. After the resistance ET program, differences were not observed in the MI

size between the infarcted groups. Further analyses showed similar increase in left

ventricle mass and relative wall thickness  – an indicator of scar formation  – in

trained groups (i.e., non-MI and MI rats), with significant differences observed

between trained-infarcted and sedentary-infarcted rats, in favour of the trained

group. These data suggest a positive cardiac remodelling elicited by resistance ET

in MI rats. To verify whether data of cardiac function could corroborate with mor-

phological data and indicate a beneficial physiological hypertrophy after resistance

ET, the cardiac function was analysed. However, results did not demonstrate altera-

tions on ejection fraction [ 19 ]. Moreover, data demonstrate ameliorated autonomic

function, indicated by a decrease in both cardiac and vascular sympathetic modula-

tion, concomitantly with an increase in the parasympathetic modulation [ 19 ].

Therefore, more evidences regarding the effects of resistance ET on MI-induced

infarcted

heart

Cardiacremodelling

Cardiacfunctioning

 ROS ̄Antioxidanactivityt  PICs

 Ventricular

dilation

 Scar

formation

Cardiac

hypertrophy

MMPs

Autonomic

̄BrS dysfunction

̄LV function

 Collagen

MI area content

Inhibition

EXERCISE

TRAINING

Fig. 9.2 Main effects of exercise training (ET) in experimental myocardial infarction (MI).
Aerobic ET performed on a rodent-adapted treadmill is the most studied method. BrS baroreflex
sensitivity, LV left ventricle, ROS reactive oxygen species, PICs proinflammatory citokynes,
MMPs matrix metalloproteinases

I.C. Moraes-Silva et al.