MELBOURNE: Sitting continuously for more than 25 minutes may reduce muscle activity and potentially contribute to health risks associated with prolonged inactivity, according to research led by scientists at Australia’s Swinburne University of Technology.
The study, published in the medical journal npj, examined how muscle activity changes during everyday periods of sitting. Researchers used specially equipped sensor shorts to monitor muscle activity and collected data from more than 7,000 sitting periods.
The findings suggest that muscle activity begins to decline when people remain seated for more than 25 minutes. Over time, reduced muscle activity may affect blood circulation and the delivery of glucose from the bloodstream to muscles, potentially contributing to an increased risk of cardiovascular disease and type 2 diabetes.
The research was led by Dr Christian Burkinridge of Swinburne University, according to the report.
Not All Sitting Is the Same
Researchers found that different types of sitting can involve different levels of muscle activity. Driving, talking with friends or working in an office may involve small movements, while watching television or films for several hours in one position can result in very low levels of physical activity.
Even small movements while sitting may be associated with better health outcomes, including lower body mass index (BMI), a smaller waist circumference and a reduced risk of cardiovascular disease.
Dr Burkinridge said muscles tend to be less active during prolonged sitting than during shorter sitting periods. However, getting up to walk or incorporating movement breaks into the day may help maintain greater muscle activity.
Simple Ways to Break Up Sitting Time
The report suggests that people who spend much of their day at a desk or in front of a mobile phone or computer can benefit from incorporating small movements into their routines.
These activities do not necessarily require strenuous exercise. Getting up to refill a glass of water, walking a few steps or changing sitting position can help introduce more movement into the day.
The researcher also offered an example of someone who spends around 10 hours sitting daily. Taking a brief movement break every 25 minutes could add up to approximately 90 minutes of additional muscle activity over the course of the day, according to the report.
The findings highlight the potential importance of reducing prolonged, uninterrupted sitting. However, the study’s reported findings concern muscle activity and its relationship with health indicators; they should not be interpreted as proof that sitting for exactly 25 minutes directly causes a heart attack or blood clots.