Khaberni - For years, public health advice has focused on a simple message: reduce sitting and increase physical activity.
While this advice seems sound on the surface, the results of two new studies suggest that the intensity of the exercise may be just as important as its duration.
According to Psychology Today, both studies used data collected from about 100,000 participants in the UK Biobank. They were followed for many years, with their activity levels monitored through wearable fitness trackers, providing researchers with objective data rather than relying on self-reported exercise logs.
"A Crucial Variable"
While both research teams analyzed the same population group, the difference in "analytical methods" highlights why exercise intensity is a critical variable for long-term health.
By studying the same group of 100,000 people using different measurement scales, the two studies provide a more comprehensive picture of how movement contributes to disease prevention and life extension.
The first study, led by researcher Jiehua Wu and colleagues from Central South University of China, focused on "volume versus intensity". By separating intense physical activity from moderate physical activity within the moderate to vigorous physical activity category, the researchers found that individuals who engaged in more intense activity were less likely to develop eight major chronic diseases.
The lead researcher of the study, Minxu Xin, said in a press release, "It appears that intense physical activity provokes specific body responses that cannot be completely replicated by less intense physical activity."
High-intensity exercise places unique demands on the cardiovascular system and the skeletal muscles, enhancing cardiopulmonary fitness and metabolic capabilities. Moreover, short periods of intense exercise are associated with reduced risks in the following eight health conditions:
1. Cardiovascular diseases: Lower incidence of serious heart diseases and strokes.
2. Atrial Fibrillation: Reduced likelihood of heart rhythm disorders.
3. Chronic respiratory diseases: Improved lung health and reduced risk of diseases such as chronic bronchitis and emphysema.
4. Type 2 Diabetes: Improved insulin sensitivity and better long-term blood sugar control.
5. Fatty liver disease: Improved liver health and metabolic functions.
6. Inflammatory diseases (such as arthritis): Reduced risk of autoimmune inflammatory diseases.
7. Chronic kidney diseases: Improved long-term vascular and organ health.
8. Dementia: Reduced risk of cognitive decline.
"Moderate to Vigorous Activity"
The second study examined a similar set of data from the UK Biobank, from a broader perspective of exercise intensity, specifically "moderate to vigorous physical activity". Unlike the previous study, which focused on prevention of specific diseases, the research team in the second study focused on overall mortality, which is a comprehensive measure of death risk for any reason.
Based on this research perspective, researcher Yehui Kai and colleagues at Hong Kong Polytechnic University found that engaging in approximately 150 minutes of moderate to vigorous physical activity per week is associated with a reduced risk of death. It is noteworthy that this benefit persisted even when the activity was performed in short, intermittent bursts throughout the day. The results suggest that simply increasing the effort level from "light and easy" to "moderate or vigorous" makes a noticeable difference.
Despite this, the concept of "moderate to intense activity" remains a fundamental distinction, although it combines quick walking and uphill running. Kai and his colleagues' study showed that engaging in moderate to intense physical activity in short and intermittent periods reduces the risk of death. They also discovered that exerting a significant effort, even to the point of mild breathlessness, offers specific protection against chronic diseases, a protection that moderate intensity physical activity may not provide as effectively.
"The Optimal Dose"
Both studies concluded that the "optimal dose" of exercise is not fixed or universally agreed upon. While researchers acknowledge that the exercise dose depends on a combination of volume (quantity), intensity (effort), and time duration, there is still ongoing debate about which specific combination triggers the strongest dose response.
In many ways, this is good news. It indicates that "increasing" the intensity of exercise can allow for shorter workouts while maintaining comprehensive protection from diseases. At the same time, it shows that periods of less intense physical activity throughout the week have significant benefits in extending life. Therefore, it is not a choice between two extremes, but more like a gradient.
Practical Tips
So, one doesn't have to be a professional athlete to benefit from these findings. Since intensity is relative, if physical activity makes someone pant to the extent that it is difficult to speak full sentences, it is considered intense physical activity. Here are some ways to increase the intensity of activity throughout the day:
• Power Minute: During the usual daily walk, add 60-second intervals of brisk walking or light jogging to raise the heart rate.
•Fast stair climbing: Instead of climbing slowly, ascend stairs at a pace that makes you breathless.
•Speedy task completion: Treat walking from the car to the store as brisk walking instead of a leisurely stroll.
•Active housework: Increase the pace of vacuuming, mopping, or gardening enough to significantly raise your heart rate and body temperature.
