ABC | Volume 114, Nº5, May 2020

Arq Bras Cardiol. 2020; 114(5):943-987 Guidelines Brazilian Cardiovascular Rehabilitation Guideline – 2020 from adequate adherence to a supervised exercise program. 87 Such adherence can also provide clinical and functional inputs that enable adequate counseling as to whether and how patients can resume sexual activity, based on the KiTOMI model, which was proposed by Brazilian authors in 2016. 88 In addition, periodic reevaluation is essential to encourage commitment andmeasure the progress and benefits obtained. Finally, it is important to establish a systematic follow-up revaluation scheme which, in addition to encouraging patient commitment, will allow measurement of the progress and benefits obtained and yield reports to support treatment adjustments. Therefore, these reports should always be sent to the patient’s primary physician, who is obviously an integral part of full clinical treatment. 6.2. Hypertension Hypertension (HTN) remains one of the leading risk factors for the development of CAD, HF, CKD, and ischemic or hemorrhagic stroke, representing a huge social and economic challenge to global public health. 89 Worldwide, the number of patients with HTN rose from 594 million in 1975 to 1.13 billion in 2015, with growth largely credited to underdeveloped and developing countries. 90 Considering that most cases of HTN are lifestyle-related, with sedentary behaviors as a prominent cause, the importance of physical exercise is clear, alongside other behavioral measures and drug therapy as indicated. 72 6.2.1. Therapeutic Benefits of Physical Exercise HTN has a complex, multifactorial pathophysiology involving structural and physiological modifications, particularly to the vasculature (increased arterial stiffness, increased arteriole wall-to-lumen ratio, capillary rarefaction), kidneys (increased plasma renin and water and sodium resorption, decreased glomerular filtration), and nervous system (increased sympathetic and chemoreceptor activity, decreased parasympathetic activity and baroreflex sensitivity). 91 The regular practice of physical exercise has a therapeutic effect on the physiological restructuring of these systems, reducing oxidative stress and inflammation, correcting baroreflex dysfunction, increasing vagal tone, decreasing sympathetic activity, reversing hypertrophic arteriolar remodeling in exercised tissues, and reducing peripheral vascular resistance, with a consequent decrease in BP levels similar, or even superior, to that provided by drug therapy. 92,93 In vascular tissue, HTN is characterized by disorganization of smooth muscle cells, increased collagen deposition, and a decreased elastin/collagen ratio, in addition to the formation of abnormal elastic fiber and internal elastic lamina with a smaller fenestrated area. 94 All of these structural changes in the vessel wall, which occur in both arteries and arterioles, increase the overall stiffness of the vasculature, with a consequent increase in pulse wave velocity, pulse pressure – the difference between systolic BP (SBP) and diastolic BP (DBP) – and hydrostatic pressure in the capillaries. These structural imbalances are compounded by endothelial dysfunction, with an increase in vasoconstrictive compounds, inflammatory mediators, and oxidizing agents, to the detriment of synthesis of vasodilating and antioxidant compounds. 95.96 Physical exercise, by increasing the tangential stress derived from the friction of blood flow on the endothelial surface of the vessel wall (commonly described by the term shear stress) positively stimulates the endothelial tissue, increasing production of antioxidant enzymes and vasodilating agents, in addition to decreasing the action of free radicals, pro-inflammatory cytokines, adhesion molecules, and vasoconstricting agents, thus restoring the balance of endothelial function. 97,98 Experimental studies 94 in spontaneously hypertensive rats have demonstrated reorganization of all vascular structures of the aorta after implementation of a period of aerobic exercise. Aerobic training promotes vascular adaptations in the conductance arteries (with decreased arterial stiffness and improved endothelial function), arterioles (by decreasing the vessel wall-to-lumen ratio), and capillaries, stimulating angiogenesis. 99,100 Thus, physical exercise has multifactorial effects on HTN, and is considered a key intervention to mitigate the burden of the disease and its comorbidities. 101 The antihypertensive effect of exercise is comparable to that of medication, 102 and both can be additive, occasionally requiring adjustments of drug dosage. The greatest evidence of benefit in BP reductions among hypertensive patients is for aerobic physical exercise, as corroborated in a meta-analysis by Cornelissen et al. which showed an average SBP reduction of 8.3 mmHg and DBP reduction of 5.2 mmHg as a result of aerobic exercise. The goal of resistance training (which also has an antihypertensive effect 103 ) is to preserve or increase muscle mass, strength, and endurance, factors that decrease the relative intensity needed to perform the activities of daily living, with consequent damping of the blood pressure response to exertion. Furthermore, resistance training may also promote improvement in baroreflex sensitivity. 104 In addition to aerobic and dynamic resistance exercises, some studies have focused on isometric (static resistance) exercises and shown significant effects in reducing BP levels. 105-107 A meta-analysis found that isometric handgrip training, performed for 12 minutes three to five times a week, reduced SBP and DBP by 5.2 and 3.9 mmHg respectively. 108 However, studies on the safety and effectiveness of isometric modalities in the long term are still lacking. 6.2.2. Indications for Physical Exercise in Hypertension Higher levels of physical activity have been associated with a decrease in the risk of developing HTN. With the advent of electronic activity trackers and ambulatory BP monitoring, it has become increasingly feasible to conduct studies that correlate physical activity with BP. 109 Physical fitness, measured objectively through graded stress tests, attenuates the increase in BP with age and prevents the development of HTN. In a cohort of 20-to-90-year-old men who were followed for 3 to 28 years, greater physical fitness decreased the rate of BP increase over time and delayed the onset of HTN. 110 Epidemiological studies have revealed that both level of physical activity and cardiorespiratory fitness are inversely associated with hypertension. 111,112 955