Sedentary lifestyle, a hidden risk with serious effects on heart health
People with sedentary behavior of more than 10 hours a day have a higher risk of suffering from heart conditions such as atrial fibrillation, heart failure, myocardial infarction, and cardiovascular mortality.
In the modern era, where technology, work models, new entertainment habits, and convenience have led us to spend long hours sitting, whether in the office, in the car, or at home; sedentary behavior has become a silent enemy with serious effects on our health.
But what is sedentary behavior and what are its consequences? It is a lifestyle characterized by a lack of regular physical activity and the predominance of activities that involve sitting or lying down for long periods. Moving less than the body needs may seem harmless, but its long-term consequences are alarming. Beyond gaining a few extra pounds, sedentary behavior increases the risk of cardiovascular diseases, diabetes, muscular disorders, and even affects our mental health.
While the World Health Organization (WHO) recommends at least 150 minutes of moderate to intense exercise per week to reduce the risk of cardiovascular diseases, the guidelines do not clearly specify how inactivity directly impacts heart health.
A new study from Mass General Brigham indicates that more than 10.6 hours of sedentary behavior per day increases the risk of atrial fibrillation (AF), myocardial infarction, heart failure, and cardiovascular death. The study, published in the Journal of the American College of Cardiology, revealed that this occurs even for people who also meet the recommended amount of exercise per week.
"Many people spend several hours a day in a sedentary state. We wanted to understand if exercise can negate the effects of this behavior," says Shaan Khurshid, MD, MPH, a cardiac electrophysiologist at Mass General Brigham who treats patients at Massachusetts General Hospital. “Overall, our findings indicate that avoiding excessive sedentary behavior is important for cardiovascular benefit, whether you are basically active or not.”
How much time do people spend on average in a sedentary lifestyle?
In Mexico, the prevalence of cardiovascular diseases has been increasing. According to the National Institute of Public Health (INSP), 24.4% of deaths in Mexico are due to cardiovascular diseases, making them one of the leading causes of death in the country. According to the 2021 National Health and Nutrition Survey (ENSANUT), 75% of Mexican adults do not meet the minimum recommendations for physical activity, which increases their cardiovascular risk. This data underscores the importance of reducing sedentary behavior, in addition to leading an active and healthy life.
Dr. Khurshid recently created a study that included nearly 90,000 people who wore activity trackers on their wrists for a week. Researchers collected data on the time and intensity of exercise, as well as sedentary time. Sedentary time was defined as all the time a person spends awake sitting, reclining, or lying down, and that involves low energy expenditure. Sleeping and standing did not count as sedentary time.
The average sedentary time was 9.4 hours a day. Researchers divided participants into 4 equal groups:
- The most sedentary group had an average sedentary time of more than 10.6 hours a day.
- The next group ranged from 9.5 to 10.6 hours a day.
- Another group ranged from 8.2 to 9.4 hours a day.
- The group with the least sedentary time had an average of less than 8.2 hours a day.
"A total of 10.6 hours seems like a lot. But if you consider someone who has an office job and then watches some television at night, it actually adds up very quickly," says Dr. Khurshid. "In the United States, an average of 9.5 hours a day is estimated. So 10.6 is higher than average, but it represents the behavior of many people."
In Mexico, according to data from the National Institute of Statistics and Geography (INEGI), 50% of the adult population is considered sedentary, reflecting the global trend of an increase in sedentary behaviors due to urban lifestyle and the use of electronic devices.
The effects of sedentary behavior on cardiovascular health
Next, the study evaluated how many people suffered from four specific cardiovascular conditions in the following 8 years. It was determined that people in the highest category of sedentary behavior (more than 10.6 hours) had a higher risk of four significant heart conditions:
- Atrial fibrillation (AF): it is one of the most common types of irregular heartbeat or arrhythmia. It can lead to blood clots, strokes, heart failure, and other complications.
- Heart failure: in heart failure, the heart does not function as well as it should. This condition can prevent the rest of the body from receiving the oxygen it needs.
- Myocardial infarction (heart attack): this medical emergency occurs when blood flow to the heart is blocked, preventing the heart from receiving enough oxygen.
- CV mortality: the study also examined how many people died from heart-related causes.
The results were particularly striking in the case of heart failure and cardiovascular death (CV). The most sedentary individuals had a 40% and 60% higher risk, respectively. Furthermore, the more days a week a person exceeded that 10.6-hour mark, the greater their risk of suffering from the four CV conditions.
"Being active is helpful, but it does not completely outweigh the risks associated with excessive sedentary behavior. Therefore, even if you are basically active, it remains important to reduce sedentary behavior," notes the specialist from Mass General Brigham.
Too much time sitting affects heart health, even if exercise recommendations are met
Interestingly, a lot of sedentary time increased the risk of heart-related problems, even in people who met the recommended amount of weekly exercise.
"We looked at people in the high sedentary behavior category and analyzed what would happen to their risk if they replaced sedentary behavior with any other activity. Even if they only replaced it with light activity. Anything less sedentary: walking, standing, basically doing anything," says Dr. Khurshid. "We observed a lower risk of heart failure and cardiovascular death. So, if something like that can be included throughout the day, our study indicates that it will be beneficial for the risk."
Dr. Khurshid hopes these findings motivate people to make small changes and adopt healthy behaviors in a way that best suits them. Recently, he concludes a study published in Circulation, which shows that “weekend warriors” have a substantially lower risk of suffering from 264 diseases compared to inactive individuals. The study concluded that concentrating physical activity in longer sessions just 1 or 2 days a week is as beneficial as spreading activity more evenly throughout the week.