THE EFFECT OF THE DURATION AND INTENSITY OF EXERCISE ON CARDIOVASCULAR HEALTH

Abstract

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity across the world. As of 2023, it's been estimated that each year, more than half a billion people are affected, with greater than 20 millions deaths. Although regular exercise is widely known to be a protective factor against CVD, the optimal combination of exercise duration and intensity for cardiovascular health improvement remains unclear. While common exercise regimens over the past several decades have included combinations of moderate and vigorous exercise, new routines include workouts that last a fraction of the time, but promise the same benefits as longer workouts. This literature review compiles current research on how exercise models, ranging from continuous moderate-intensity training to emerging high-intensity, short-duration protocols such as 12-week sprint interval training, affect key cardiovascular health metrics, including blood pressure, heart rate, vascular resistance, and myocardial function. This review explores the physiological mechanisms behind the benefits induced by exercise, such as mitochondrial biogenesis and angiogenesis, while also considering the role of afterload and preload on blood pressure. Evidence from large longitudinal studies and targeted clinical trials demonstrates that both increased exercise intensity and duration are associated with reduced CVD risk and mortality, though diminishing benefits are observed beyond certain thresholds of intensity. Additionally, the review evaluates the value of recently popularized, time-efficient exercise routines in comparison to established guidelines. The findings highlight the multifactorial nature of cardiovascular adaptation to exercise and underscore the importance of individualized exercise prescriptions to optimize cardiovascular health in diverse populations.