A new study from the University of Turku showed that reducing daily sitting prevented back pain from worsening over six months. The results, published in BMJ Open, strengthen the current understanding of the link between activity and back pain as well as the mechanisms related to back pain.
Intuitively, it is easy to think that reducing sitting would help with back pain, but previous research data is surprisingly scarce. The study from the Turku PET Centre and UKK Institute in Finland investigated whether reducing daily sitting could prevent or relieve back pain among overweight or obese adults who spend the majority of their days sitting. The participants were able to reduce their sitting by 40 min/day, on average, during the six-month study.
“Our participants were quite normal middle-aged adults, who sat a great deal, exercised little, and had gained some extra weight. These factors not only increase the risk for cardiovascular disease but also for back pain,” says Doctoral Researcher and Physiotherapist Jooa Norha from the University of Turku in Finland.
Previous results from the same and other research groups have suggested that sitting may be detrimental for back health but the data has been preliminary.
The figure presents the change in back pain intensity on a scale from 0 to 10. The blue bars represent individuals in the intervention group that reduced sitting and the red bars represent the control participants who did not change their sitting habits. Most of the participants in the intervention group decreased their back pain whereas the back pain in the control participants tended to increase.
Robust methods for studying the mechanisms behind back pain
The researchers also examined potential mechanisms behind the prevention of back pain.
”However, we did not observe that the changes in back pain were related to changes in the fattiness or glucose metabolism of the back muscles,” Norha says.
Individuals with back pain have excessive fat deposits within the back muscles, and impaired glucose metabolism, or insulin sensitivity, can predispose to pain. Nevertheless, back pain can be prevented or relieved even if no improvements in the muscle composition or metabolism take place. The researchers used magnetic resonance imaging (MRI) and PET imaging that is based on a radioactive tracer to measure the back muscles.
“If you have a tendency for back pain or excessive sitting and are concerned for your back health, you can try to figure out ways for reducing sitting at work or during leisure time. However, it is important to note that physical activity, such as walking or more brisk exercise, is better than simply standing up,” Norha points out.
The researchers wish to remind that switching between postures is more important than only looking for the perfect posture.
Replacing sitting with as little as a few minutes of daily moderate exercise measurably improves heart health, according to new research from the University of Sydney and UCL.
The study, published in the European Heart Journal, is the first to assess how different movement patterns throughout the 24-hour day are linked to cardiovascular health. Although it was an observational study and could not attribute causation, it added to the growing body of evidence surrounding inactivity, especially sitting.
It is the first evidence to emerge from the international Prospective Physical Activity, Sitting and Sleep (ProPASS) consortium.
In this British Heart Foundation (BHF)-supported study, researchers at UCL analysed data from six studies, including 15 246 people from five countries, to see how movement behaviour across the day is associated with heart health, as measured by six common indicators. Each participant used a wearable device on their thigh to measure their activity throughout the 24-hour day and had their heart health measured.
The researchers identified a hierarchy of behaviours that make up a typical 24-hour day, with time spent doing moderate-vigorous activity providing the most benefit to heart health, followed by light activity, standing and sleeping compared with the adverse impact of sedentary behaviour.
The team modelled what would happen if an individual changed various amounts of one behaviour for another each day for a week, in order to estimate the effect on heart health for each scenario. When replacing sedentary behaviour, as little as five minutes of moderate-vigorous activity had a noticeable effect on heart health.
For a 54-year-old woman with an average BMI of 26.5, for example, a 30-minute change translated into a decrease in BMI of 0.64 (2.4%) Replacing 30 minutes of daily sitting or lying time with moderate or vigorous exercise could also translate into a 2.5cm (2.7%) decrease in waist circumference or a 1.33 mmol/mol (3.6%) decrease in HBa1c.
Dr Jo Blodgett, first author of the study from UCL Surgery & Interventional Science and the Institute of Sport, Exercise & Health, said: “The big takeaway from our research is that while small changes to how you move can have a positive effect on heart health, intensity of movement matters. The most beneficial change we observed was replacing sitting with moderate to vigorous activity – which could be a run, a brisk walk, or stair climbing – basically any activity that raises your heart rate and makes you breathe faster, even for a minute or two.”
The researchers pointed out that although time spent doing vigorous activity was the quickest way to improve heart health, there are ways to benefit for people of all abilities – it’s just that the lower the intensity of the activity, the longer the time is required to start having a tangible benefit. Using a standing desk for a few hours a day instead of a sitting desk, for example, is a change over a relatively large amount of time but is also one that could be integrated into a working routine fairly easily as it does not require any time commitment.
Those who are least active were also found to gain the greatest benefit from changing from sedentary behaviours to more active ones.
Professor Emmanuel Stamatakis, joint senior author of the study from the Charles Perkins Centre and Faculty of Medicine and Health at the University of Sydney, said: “A key novelty of the ProPASS consortium is the use of wearable devices that better differentiate between types of physical activity and posture, allowing us to estimate the health effects of even subtle variations with greater precision.”
Though the findings cannot infer causality between movement behaviours and cardiovascular outcomes, they contribute to a growing body of evidence linking moderate to vigorous physical activity over 24 hours with improved body fat metrics. Further long-term studies will be crucial to better understanding the associations between movement and cardiovascular outcomes.
Professor Mark Hamer, joint senior author of the study from UCL Surgery & Interventional Science and the Institute of Sport, Exercise & Health, said: “Though it may come as no surprise that becoming more active is beneficial for heart health, what’s new in this study is considering a range of behaviours across the whole 24-hour day. This approach will allow us to ultimately provide personalised recommendations to get people more active in ways that are appropriate for them.”
James Leiper, Associate Medical Director at the British Heart Foundation, said: “We already know that exercise can have real benefits for your cardiovascular health and this encouraging research shows that small adjustments to your daily routine could lower your chances of having a heart attack or stroke. This study shows that replacing even a few minutes of sitting with a few minutes of moderate activity can improve your BMI, cholesterol, waist size, and have many more physical benefits.
“Getting active isn’t always easy, and it’s important to make changes that you can stick to in the long-term and that you enjoy – anything that gets your heart rate up can help. Incorporating ‘activity snacks’ such as walking while taking phone calls, or setting an alarm to get up and do some star jumps every hour is a great way to start building activity into your day, to get you in the habit of living a healthy, active lifestyle.”
While evidence suggests that prolonged sitting is hazardous to health, the optimum interval and quantity for exercise breaks has been unclear. Now, exercise physiologists can provide an answer: just five minutes of walking every half hour during periods of prolonged sitting can offset some of the most harmful effects.
The study, led by Keith Diaz, PhD, associate professor of behavioral medicine at Columbia University Vagelos College of Physicians and Surgeons, was published online in Medicine & Science in Sports & Exercise.
Unlike other studies that test one or two activity options, Diaz’s study tested five different exercise ‘snacks’: one minute of walking after every 30 minutes of sitting, one minute after 60 minutes; five minutes every 30; five minutes every 60; and no walking.
“If we hadn’t compared multiple options and varied the frequency and duration of the exercise, we would have only been able to provide people with our best guesses of the optimal routine,” Diaz says.
Each of the 11 adults who participated in the study came to Diaz’s laboratory, where participants sat in an ergonomic chair for eight hours, rising only for their prescribed exercise snack of treadmill walking or a bathroom break. Researchers kept an eye on each participant to ensure they did not over- or under-exercise and periodically measured the participants’ blood pressure and blood sugar (key indicators of cardiovascular health). Participants were allowed to work on a laptop, read, and use their phones during the sessions and were provided standardized meals.
The optimal amount of movement, the researchers found, was five minutes of walking every 30 minutes. This was the only amount that significantly lowered both blood sugar and blood pressure. In addition, this walking regimen had a dramatic effect on how the participants responded to large meals, reducing blood sugar spikes by 58% compared with sitting all day.
Taking a walking break every 30 minutes for one minute also provided modest benefits for blood sugar levels throughout the day, while walking every 60 minutes (either for one minute or five minutes) provided no benefit.
All amounts of walking significantly reduced blood pressure by 4 to 5 mmHg compared with sitting all day. “This is a sizeable decrease, comparable to the reduction you would expect from exercising daily for six months,” says Diaz.
The researchers also periodically measured participants’ levels of mood, fatigue, and cognitive performance during the testing. All walking regimens, except walking one minute every hour, led to significant decreases in fatigue and significant improvements in mood. None of the walking regimens influenced cognition.
“The effects on mood and fatigue are important,” Diaz says. “People tend to repeat behaviors that make them feel good and that are enjoyable.”
The Columbia researchers are currently testing 25 different doses of walking on health outcomes and testing a wider variety of people: Participants in the current study were in their 40s, 50s, and 60s, and most did not have diabetes or high blood pressure.
“What we know now is that for optimal health, you need to move regularly at work, in addition to a daily exercise routine,” says Diaz. “While that may sound impractical, our findings show that even small amounts of walking spread through the work day can significantly lower your risk of heart disease and other chronic illnesses.”
