Physical Activity and Anti-Aging: Prevention of Metabolic and Cardiovascular Diseases Through Exercise

Lack of exercise is recognized as a clear factor in the risk of metabolic and cardiovascular diseases. Recently, not only lack of exercise but also an increase in sedentary time has been reported to be associated with obesity-related metabolic and cardiovascular diseases [1]. Therefore, not only conscious physical activity in daily life but also physical activity through daily activities such as housework, shopping, commuting, etc., should be actively considered as a broad definition of exercise. In addition to traditional low-intensity activities such as walking, moderate- to high-intensity exercise has also been recognized as beneficial for the prevention of metabolic and cardiovascular diseases due to increases in type II fiber in peripheral muscle tissue, increases in capillary beds, and increases in peripheral circulation blood volume [2]. The effects of exercise in the metabolic and cardiovascular areas, such as hemoglobin A1c (HbA1c), HDL cholesterol, blood pressure values, and specific numbers for weight loss in obesity cases, have also been calculated by meta-analysis [3] (Table 83.1). The lowering effect of exercise on resting systolic/diastolic blood pressure is 3.4/2.5 mmHg, and it is said that about 60–70% have a blood pressure-lowering effect with exercise therapy. This effect is generally comparable to the effect of the first dose of a blood pressure-lowering diuretic. Regarding blood sugar, a 0.8% reduction in HbA1c with 30 min of moderate exercise twice or more per week, and even greater effects with the addition of resistance exercise, have been reported. These numbers are the effects of short-term exercise, and it is difficult to calculate the numbers for long-term exercise continuation, and epidemiological analysis is considered useful for long-term exercise effects. These effects can potentially be obtained simultaneously through exercise, which is interesting. The mechanism of the blood pressure-lowering effect of exercise can also be compared with drugs. In addition to the effect as a blood pressure-lowering diuretic, the inhibition of sympathetic nerve function can be seen as the action of a β-blocker, and the improvement of endothelial function can be seen as part of the effect of Ca antagonists or ACE inhibitors, ARB drugs. Various mechanisms are considered for the specific mechanism of the exercise effect (Fig. 83.1). Recently, static stretching as a vascular stretch has been reported to activate vascular endothelial function and show anti-atherosclerotic effects [4]. These reports indicate the usefulness of stretching as a new exercise therapy in the cardiovascular area and atherosclerosis, different from traditional aerobic exercise and resistance training. The improvement of joint and tendon mobility by stretching is thought to contribute to the increase in exercise volume, and it is necessary to actively perceive flexibility and stretching as the third exercise. Skeletal muscles secrete hormones and cytokines collectively referred to as myokines, which have been reported to affect insulin sensitivity and various metabolisms, indicating the importance of skeletal muscles in metabolic diseases [5] (Fig. 83.2). Irisin, which was initially noticed, is related to fat metabolism, obesity, and atherosclerosis. Brain-derived neurotropic factor (BDNF) is said to be involved in neural function and cognitive function, and is also useful for preventing dementia in the elderly. Recently, myonectin, which is involved in the suppression of skeletal muscle metabolism, has also been noticed. With the elucidation of these myokines, the importance of resistance training as a stimulus to the skeletal muscle system along with traditional aerobic exercise is suggested. Also, resistance exercise as a muscle stimulus without skeletal muscle hypertrophy can be expected to have sufficient effects on metabolic diseases. Furthermore, skeletal muscle mass (strength) itself has been reported to be useful for the prevention and improvement of lifestyle-related diseases. Therefore, when considering resistance exercise, it is necessary to broadly perceive it from high-load intensity aimed at increasing muscle mass and strength to low intensity aimed only at muscle stimulation. Even 5 min of exercise can have an effect, so it is important to actively exercise even for a short time. Regarding exercise frequency, there are reports that even once a week is effective for primary prevention of cardiovascular diseases and other mortality rates. Considering the effects of the aforementioned myokines, if you only look at the simple energy consumption in muscles due to exercise, the diet effect of exercise is small, but if you consider the metabolic effects of myokines other than energy consumption, exercise can be more useful for dieting than imagined.