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The notion that exercise training is cardioprotective against IRI is well estab-lished in animal models [ 71 , 72 ] and human epidemiological studies [ 73 – 75 ]. In
fact, physically active individuals are less susceptible to cardiovascular events and
have a greater survival rate following a heart attack in comparison with their inac-
tive counterparts [ 71 , 73 ]. As for experimental settings, well-controlled animal stud-
ies beginning in the late 1970s have provided convincing evidence that long and
short-term aerobic exercise elicit cardioprotection against coronary artery occlusion
[ 5 – 8 , 10 – 12 , 76 , 77 ].
Data on the cardioprotective effect of long-term (weeks to months) and short-term exercise (1–5 days) against IRI as well as its time course and the influence of
exercise intensity are presented in the next sections.
4.1 Long-Term Exercise
The study of McElroy et al. [ 76 ] was one of the first to demonstrate that regular
bouts of exercise training were capable to confer cardioprotection. In their study,
rats were submitted to swimming 1 h/day, 5 days/week for 5 weeks and 24 h after
the end of the training the rats underwent left coronary occlusion. Following 48 h
after surgery, the authors observed a reduction in infarct size by 30% of exercised
rats in comparison to controls (21.5 ± 1.9% vs 31.3 ± 2.6%; P < 0.05). Similarly,
Brown et al. [ 5 ] observed an enhanced cardiac function and 25% reduction in
the infarcted area among animals trained for 20-week after 1 h of ischemia and
Fig. 10.3 Number of citations per year since 1987 found on pubmed using the terms “exercise”
and “cardioprotection”
10 Cardiac Ischemia/Reperfusion Injury: The Bene cial Effects of Exercise