**1.4 Resistance training and prevention and management of cardiovascular disease (CVD)**

It is explicit that RT has been recognised for its value in improving the health of athletes and the general public. However, only recently has scientific evidence emerged substantiating its benefits in the prevention and management of CVD [35]. This is especially true given RT's unique benefits over other modes of physical activity, especially improving the often overlooked non-traditional CVD risk factors of muscle mass and strength loss [23–25].

The evidence for a blood pressure-lowering effect of RT remains scarce [36]. However, when such evidence is forthcoming it provides confirmation for the potential of RT in the prevention and treatment of high blood pressure in normo- and even hypertensive patients [37, 38]. Additionally, some studies even demonstrate that RT is equally or more effective than aerobic training at doing so [39]. What is especially important to note is that little/no RT studies have reported serious adverse events in even hypertensive participants [36].

A reduction in cholesterol levels are considered the gold standard in preventative cardiovascular medicine [40]. This is why it is essential that much evidence supports the role that RT improves HDL-cholesterol whilst reducing total cholesterol, LDL-cholesterol and triglycerides in adults [41–43]. What is particularly interesting is that RT shows a stronger association than aerobic exercise when attempting to improve HDL-cholesterol [44, 45]. It appears that an increased volume (via increased numbers of sets or repetitions), rather than intensity or load, has a greater impact on lipid profiles [46].

While CRF improvements following RT are not as substantial as those following a period of aerobic training [47], the evidence that RT does indeed increase CRF [36] is critical, since an enhanced CRF is associated with a lower risk of all-cause mortality and cardiovascular events [48]. Interestingly, both low- and high-intensity RT have demonstrated to improve CRF, albeit via different proposed mechanisms, such as an increased Type IIa muscle activity, increases in leg strength (i.e. for pedal thrust and efficiency of movement), improvements in oxidative enzymes [49]. However, many of the CRF adaptations to RT appear to be dependent on a higher volume of training [50].

More than 39% (1.9 billion) of adults were found to be overweight and 13% (650 million) obese in 2016 [51]. This is in addition to over 340 million children and adolescents being found to be overweight or obese in 2016 [51]. This is problematic in that overweight and obesity are associated with an increased incidence of various CVDs, such as diabetes, hypertension, and metabolic syndrome [52]. It is this CVD risk factor in which the effect of RT on body composition is unique when compared to other modes of physical activity. Specifically, RT has the ability to increase muscle mass, while simultaneously reducing fat mass [33, 53]. Further, RT offers an alternative to other modes of physical activity that may not be tolerated as well by individuals who are already overweight or obese, due to the excess body weight increasing the intensity (and perceived exertion) of weight-bearing activity [54, 55]. Another reason or barrier limiting participation in aerobic-type activities may arise from an initially low CRF [54, 56].

The increasing prevalence of diabetes suggests a clear need for effective diabetes prevention and management approaches [57, 58]. As stated previously, RT is unique in its ability to prevent overweight and obesity and it is for this reason that RT is receiving increasing recognition as a cornerstone in the prevention and treatment of type 2 diabetes [59, 60]. In this regard, emerging research suggests that RT has the power to combat metabolic dysfunction in patients with type 2 diabetes. Some of the beneficial adaptations exerted by RT include increased GLUT4 translocation in skeletal muscle, increased insulin sensitivity and restored metabolic flexibility. Further, an increased energy expenditure and excess post-exercise oxygen consumption (EPOC) in response to RT may be other beneficial effects [60]. In fact, it appears that RT can improve glycemic control and insulin sensitivity likely even more than aerobic training [61, 62].

#### *Importance of Resistance Training in the Management of Cardiovascular Disease Risk DOI: http://dx.doi.org/10.5772/intechopen.99710*

Epidemiological studies have demonstrated the role of diet as a secondary CVD risk factor, as it has an important role to play in other CVD risk factors, such as hypertension, dyslipidemia, diabetes and obesity [63]. The role of diet in CVD development is complex and involves many dietary factors, including *inter alia* an excessive dietary intake of fat (particularly saturated fat), excessive intake of cholesterol, high intakes of certain carbohydrates (i.e. fructose and sucrose), excessive salt intake, excessive alcohol consumption and an inadequate intake of fiber [64]. Although research on the effects of RT on dietary patterns and intake is limited, most studies demonstrate that RT is unable to alter self-selected food intake or food preference [64–67]. However, cross-sectional studies do exist that demonstrate athletes engaging in RT have a decreased dietary intake of fat, even when compared to aerobic athletes [68]. While it seems RT may have no effect on dietary preferences, RT may affect diet indirectly by offsetting the effects of a poor diet. In this regard, since RT increases nitrogen retention, enhances protein synthesis and improves the expression of insulin-like growth factor in skeletal muscle, the anabolic potential of RT is useful in counteracting the catabolism experienced during CVD, such as interleukin-mediated myopathy of chronic heart failure, myopathy secondary to corticosteroid use in cardiac transplantation and during energy restriction for obesity management [69].

Much evidence exists identifying the mechanisms by which psychological factors, such as stress, depression, and anxiety and impact CVD [70]. In addition to RT's numerous physical benefits, the effect of RT on psychological factors is well documented. In this regard, the demonstrated mental health benefits of RT include decreased symptoms of depression, increased self-esteem, increased self-efficacy, increased, physical self-concept, improved cognitive ability and enhanced social interaction [71–73]. Specifically relating to CVD, it appears that RT may provide unique psychological benefits when compared to other physical activity modalities. This is because psychological benefits may be more related to reductions in body fat than changes in strength or fitness [72, 73]. Therefore, RT could be an alternative to aerobic training for some individuals in the biological and psychological management of adolescent obesity [72, 73].
