What happens to the heart of adolescents when they are too sedentary – breaking latest news

In adolescents, a sedentary life can increase the heart size three times more than with moderate or vigorous physical activity. the conclusion of a study published in the Scandinavian Journal of Medicine & Science in Sports and conducted by the University of Eastern Finland in collaboration with the Universities of Bristol and Exeter in the United Kingdom.

Damage to health caused by a sedentary lifestyle

Recent reports from the World Health Organization have found that over 80% of adolescents worldwide do not get enough physical activity daily. Physical inactivity is known to increase the risk of developing numerous non-communicable diseases such as cardiovascular disease, type 2 diabetes and some types of cancer. Today in Italy 48% of the general population is obese (more than 10%) or overweight (about 38%). According to the Istituto Superiore di Sanit, a sedentary lifestyle causes 9% of cardiovascular disease, 11% of type 2 diabetes, 16% of breast cancer and 16% of colon cancer. straight. The situation of childhood obesity is even more worrying: Italy is the region of Europe where the highest number of overweight children is recorded. 44.8% of Italians do not practice an adequate level of physical activity (4 worst OECD country in 2019), a percentage that reaches 94.5% in children, the last country in the OECD (data from Osservatorio Valore Sport-edition 2023 edited by of European House Ambrosetti).

The effect of a sedentary lifestyle on the structure of the heart

In the pediatric population, most studies investigating movement have focused oneffect of sedentary lifestyle and physical activity in relation to cardiometabolic health, i.e blood pressure, insulin resistance, blood fats e body mass index. However, there is an important knowledge gap on the effects of sedentary lifestyle and physical activity on heart structure and function, particularly among boys
.

And increased left ventricular massindicating an enlarged or hypertrophied heart, and a impaired left ventricular functionwhich indicates reduced heart function, can in combination or independently lead to a increased risk of heart failuremyocardial infarction, stroke and premature cardiovascular death.

The increase in heart mass

The Finnish study set out to investigate precisely this still understudied aspect: what happens to the morphology of the heart of sedentary adolescents? And to those who carry out physical activity? To do this, the scientists used data from the University of Bristol’s Children of the 90s study which included 530 17-year-old adolescents with complete data on body mass (fat and lean), glucose, lipids, markers of inflammation, insulin level, smoking habit, family history of cardiovascular diseases, heart function, measurement of the period of physical activity and sedentary lifestyle with accelerometer.

The adolescents led a sedentary lifestyle for nearly 8 hours a day and approximately 49 minutes of moderate to vigorous physical activity. it transpired that both sedentary lifestyle and moderate to vigorous physical activity were linked to increased left ventricular mass although the increase in heart mass associated with the sedentary period was three times higher the increase associated with moderate or vigorous physical activity
. This result was observed in adolescentsi regardless of their obesity statusbetween adolescents who were of normal weight and those who were overweight or obese.

It is important to underline another aspect: light physical activity is not resulted associated still increased heart mass, but was instead connected to one better heart function.

A still unknown mechanism

the first time that a correlation between a sedentary lifestyle and an increase in heart mass has been observed. In the literature, many works have linked obesity and the enlargement of the heart chambers due to the fact that the heart has to make a greater effort to supply an increased body mass. But in this new Scandinavian study sedentary lifestyle unrelated to obesity: l’cardiac hypertrophy in fact, it was observed in all sedentary people, both overweight and of normal weight. The study is very well constructed but complex since on the one hand it investigates and studies accurately, through echocardiography, the structural modifications of the heart linked to the different degrees of physical exercise, on the other hand it takes into study a growing population of adolescents , in which the cardiac maturation linked to puberty is underway, the comment of Dr Peter Palermo, Head of Cardiology Rehabilitation Monzino hospital in Milan. However, they certainly need to be better investigated reasons of the increase in heart mass among sedentary people – he adds – because the mechanismprima vista incongruous subtraction unknown. Certainly the final message of the study, based on the evidence and data obtained, underlines the need for limit sedentary lifestyle and encourage physical exercise even mild to moderate as a lifestyle precisely because this attitude leads to an improvement in the structural and functional “health” of the heart in young people.

What does physiology say

In fact, physiology tells us that cardiac work depends on the type of exercise physical and give clinical condition of the patient – continues Dr. Pietro Palermo – for example in those who have high blood pressure or in any case in those who do isometric exercise, i.e. who contracts the muscles without joint movement, such as lifting weights, undergoes a myocardial hypertrophy. This is because the heart is a muscle and when it has to work against a pressure load, the heart muscle cell, in response, becomes hypertrophic, i.e. it enlarges and there are structural changes of the heart evident on echocardiographic examination (and other instrumental investigations such as magnetic resonance) defined as “concentric” myocardial hypertrophywhich leads to a increase in wall thickness, the reduction of the ventricular distending capacity and the reduction of the intraventricular diameter. Conversely theisotonic exercisesuch as running or cycling, lead to dilation of the heart due to prolonged “volume” overload and lead to the development “eccentric” hypertrophy which determines an increase in wall thickness and intraventricular diameter (the thickness/radius ratio does not increase as in the previous case but remains within the normal range). These structural responses of the heart are well known in the adult subject while the evaluation in the young subject in the process of maturing is more complex since biochemical, hormonal factors, insulin and various enzymes also intervene in a different way.

Those who engage in light to moderate physical activity have been shown to have better heart function data. The study reiterates that a sedentary lifestyle is not good for health. Doing physical activity, on the other hand, has benefits. play amoderate or mild activityrecommended in all guidelines, appears to be the best choice because it determines structural modifications of the heart favorable to a reduction of the risk for cardiovascular diseases (both in the adult and in the young age). This is the desired primary prevention concludes Dr. Palermo.

Cost-benefit

This new job – he concluded Andrew Agbaje, physician and clinical epidemiologist at the University of Eastern Finland, one of the authors of the study – expands our knowledge on the effects of a sedentary life, also in relation to cardiac health. It is known that among adults, a 5 g/m2 increase in heart mass can increase the risk of cardiovascular disease and death by 7-20%. Engaging in moderate to vigorous physical activity also slightly enlarged the heart, but that seems like an acceptable “negative side effect” considering many of the other health benefits of moderate to vigorous exercise.