It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, October 04, 2024
Eyes on the fries: how our vision creates a food trend
How we rate food is influenced by the food we’ve just seen
University of Sydney
image:
Lead author Professor David Alais from the School of Psychology at the University of Sydney.
Human judgement of food images is influenced by judgements that precede it
Experiment tested reactions of more than 600 people making food choices
Highly relevant given widespread use of Uber Eats or phone-based menus
Finding could assist treatments for eating disorders or assist with food marketing
Research at the University of Sydney has revealed that we don’t judge food simply on its merits but are influenced by what we have seen beforehand, a cascading phenomenon known as ‘serial dependence’.
The research, published today in the high-impact journal Current Biology, was conducted by Professors David Alais and Thomas Carlson in the School of Psychology at the University of Sydney working in collaboration with Professor David Burr at the University of Florence.
Their study shows when people rate food images for appeal and calorie content, the evaluation is not made in isolation. Instead, it is subtly biased towards the judgement that preceded it.
Serial dependence arises when people make a series of sequential choices. In the context of food, if a person rates a food as very appealing, they are likely to rate the next food image more favourably, regardless of its calorie content or appeal.
It works the other way, too: a preceding unappealing food makes a current food less appealing.
The findings could assist psychologists to develop treatments for people with eating disorders to eat more or less food, and may help marketers in the presentation of food menus.
Lead author Professor Alais said: “The experimental conditions for serial dependence are not very different from our everyday experiences with food images, such as when we scan a food delivery menu or browse a menu on our phone. Serial dependence, therefore, might be affecting millions of food choices every day.”
The researchers conducted experiments with more than 600 participants who rated various food images for both calorie content and appeal. The results revealed a clear pattern of serial dependence: participants’ ratings tended to follow their previous rating.
For instance, a high rating for one food item led to a higher rating for the subsequent item, creating a chain reaction of evaluations that are interconnected rather than independent.
While the study found that men tended to rate high calorie food slightly higher than women, the overall serial dependence effect was not sex dependent and was similar for all.
“This study highlights the cognitive biases that come into play when we evaluate food,” Professor Alais said. “Our brains are wired to assimilate information from previous stimuli, just as we might be drawn to a particular dish after seeing a similar one rated highly.”
Co-author Professor Carlson said: “Our previous work has shown that the visual brain encodes the perceived caloric content of foods in just milliseconds. It will be fascinating to see the interplay between these cognitive biases and visual processing in future work.”
Beyond the immediate interest to visual neuroscientists exploring how our brain processes images, this research has potential useful applications.
For food marketers and restaurateurs, understanding serial dependence could inform strategies to enhance the appeal of their menu offerings. By placing high-appeal items or calorie-rich foods in a sequence, they could influence consumer perceptions and potentially drive sales.
This research also has potential to play a role in clinical settings, particularly in addressing obesity, compulsive eating, bulimia and related eating disorders.
By recognising how previous food ratings can affect subsequent choices, cognitive behavioural therapies could be tailored to leverage these findings, helping people reshape their perceptions and decision-making processes around food.
This approach could promote healthier eating habits and support effective interventions for those struggling with eating disorders.
The researchers declare no competing interests. Researchers received financial support from the Australian Research Council and the European Research Council.
Polar sea ice is ever-changing. It shrinks, expands, moves, breaks apart, reforms in response to changing seasons, and rapid climate change. It is far from a homogenous layer of frozen water on the ocean’s surface, but rather a dynamic mix of water and ice, as well as minute pockets of air and brine encased in the ice.
New research led by University of Utah mathematicians and climate scientists is generating fresh models for understanding two critical processes in the sea ice system that have profound influences on global climate: the flux of heat through sea ice, thermally linking the ocean and atmosphere, and the dynamics of the marginal ice zone, or MIZ, a serpentine region of the Arctic sea ice cover that separates dense pack ice from open ocean.
In the last four decades since satellite imagery became widely available, the width of the MIZ has grown by 40% and its northern edge has migrated 1,600 kilometers northward, according to Court Strong, a professor of atmospheric sciences.
“It has also shifted toward the pole while the size of the sea ice pack has declined,” said Strong, a co-author on one of two studies published by U scientists in recent weeks. “Most of these changes have happened in the fall, around the time when sea ice reaches its seasonal minimum.”
A tale of two studies, one north and one south
This study, which adapts a phase transition model normally used for alloys and binary solutions on laboratory scales to MIZ dynamics on the scale of the Arctic Ocean, appears in Scientific Reports. A second study, published in the Proceedings of the Royal Society Aand based on field research in the Antarctic, developed a model for understanding the thermal conductivity of sea ice. The issue cover featured a photo exposing regularly spaced brine channels in the bottom few centimeters of Antarctic sea ice.
Ice covering both polar regions has sharply receded in recent decades thanks to human-driven global warming. Its disappearance is also driving a feed-back loop where more of the sun energy’s is absorbed by the open ocean, rather than getting reflected back to space by ice cover.
Utah mathematics professors Elena Cherkaev and Ken Golden, a leading sea ice researcher, are authors on both studies. The Arctic study led by Strong examines the macrostructures of sea ice, while the Antarctic study, led by former Utah postdoctoral researcher Noa Kraitzman, gets into its micro-scale aspects.
Sea ice is not solid, but rather is more like a sponge with tiny holes filled with salty water, or brine inclusions. When the ocean water below interacts with this ice, it can set up a flow that allows heat to move more quickly through the ice, just as when you stir a cup of coffee, according to Golden. Researchers in the Antarctic study used advanced mathematical tools to figure out how much this flow boosts heat movement.
The thermal conductivity study also found that new ice, as opposed to the ice that remains frozen year after year, allows more water flow, thereby enabling greater heat transfer. Current climate models could be underestimating the amount of heat moving through the sea ice because they don’t fully account for this water flow. By improving these models, scientists can better predict how fast sea ice melts and how this affects the global climate.
While the aspects of ice investigated in the two studies are quite different, the mathematical principles for modeling them are the same, according to Golden.
“The ice not a continuum. It’s a bunch of floes. It’s a composite material, just like the sea ice with the tiny brine inclusions, but this is water with ice inclusions,” said Golden, describing the Arctic’s marginal ice zone. “It’s basically the same physics and math in a different context and setting, to figure out what are the effective thermal properties on the big scale given the geometry and information about the floes, which is analogous to giving detailed information about the brine inclusions at the sub-millimeter scale.”
Golden is fond of saying what happens in the Arctic does not stay in the Arctic. Changes in the MIZ are certainly playing out elsewhere in the world in the form of disrupted climate patterns, so it is critical to understand what it’s doing. The zone is defined as that part of the ocean surface where 15% to 80% is covered by sea ice. Where the ice cover is greater than 80% it is considered pack ice and less than 15% it’s considered to be the outer fringes of open ocean.
A troubling picture from space
“The MIZ is the region around the edge of the sea ice, where the ice gets broken into smaller chunks by waves and melting,” Strong said. “Changes in the MIZ are important because they affect how heat flows between the ocean and atmosphere, and the behavior of life in the Arctic, from microorganisms to polar bears, and navigating humans.”
With the advent of quality satellite data beginning in the late 1970s, scientific interest in the MIZ has grown, since now its changes are easily documented. Strong was among those who figured out how to use imagery shot from space to measure the MIZ and document alarming changes.
“Over the past several decades, we’ve seen the MIZ widen by a dramatic 40%,” Strong said.
For years, scientists have scrutinized sea ice as a so-called “mushy layer.” As a metal alloy melts or solidifies from liquid, either way it passes through a porous or mushy state where the liquid and solid phases coexist. Freezing salt water is similar, resulting in a pure ice host with liquid brine pockets, which is particularly porous or mushy in the bottom few centimeters nearest the warmer ocean, with vertical channels called “chimneys” in mushy layer language.
Strong’s team tested whether previously modeled mushy layer physics could be applied to the vast reaches of the MIZ. According to the study, the answer is yes, potentially opening a fresh look at a part of the Arctic that is in constant flux.
In short, the study proposed a new way of thinking about the MIZ, as a large-scale phase transition region, similar to how ice melts into water. Traditionally, melting has been viewed as something that happens on a small scale, like at the edges of ice floes. But when the Arctic is viewed in its entirety, the MIZ can be seen as a broad transition zone between solid, dense pack ice and open water. This idea helps explain why the MIZ is not just a sharp boundary, but rather a “mushy” region where both ice and water coexist.
“In climate science, we often use very complex models. This can lead to skillful prediction, but can also make it difficult to understand what’s happening physically in the system,” Strong said. “The goal here was to make the simplest possible model that can capture the changes we’re seeing in the MIZ, and then to study that model to gain insight into how the system works and why it’s changing.”
The focus in this study was to understand the MIZ’s seasonal cycle. The next step will be applying this model to better understand what drives MIZ trends observed over the past few decades.
The study “Homogenization for convection-enhanced thermal transport in sea ice” appeared Aug. 28 in the journal Proceedings of the Royal Society A. Co-authors include Rebecca Hardenbrook of Dartmouth University and Huy Dinh, N. Benjamin Murphy, Elena Cherkaev and Jingyi Zhu of the U’s Department of Mathematics. The Arctic study titled, “Multiscale mushy layer model for Arctic marginal ice zone dynamics,” appeared Sept. 3 in Scientific Reports. Funding for this research came from the National Science Foundation and the U.S. Office of Naval Research.
Multiscale mushy layer model for Arctic marginal ice zone dynamics
New MBARI research reveals the dynamic processes that sculpt the Arctic seafloor
An international team of researchers used MBARI’s advanced underwater technology to document how melting permafrost and new ice formation contribute to the dramatic underwater landscape in a remote area of the Arctic
MBARI researchers, working alongside a team of international collaborators, have discovered large underwater ice formations at the edge of the Canadian Beaufort Sea, located in a remote region of the Arctic. This discovery reveals an unanticipated mechanism for the ongoing formation of submarine permafrost ice.
In a previous MBARI study, researchers observed enormous craters on the seafloor in this area, attributed to the thawing of ancient permafrost submerged underwater. While exploring the flanks of these craters on a subsequent expedition, MBARI researchers and collaborators from the Korea Polar Research Institute (KOPRI), the Korea Institute of Geoscience and Mineral Resources, the Geological Survey of Canada, and the U.S. Naval Research Laboratory observed exposed layers of submarine permafrost ice.
The recently discovered layers of ice are not the same as the ancient permafrost formed during the last ice age, but rather were created under present-day conditions. This ice is produced when deeper layers of ancient submarine permafrost melt, creating brackish groundwater that rises and refreezes as it approaches the seafloor, where the ambient temperature is approximately -1.4 degrees Celsius (29.5 degrees Fahrenheit).
The complex morphology of the seafloor in this region of the Arctic tells a story that involves both the melting of ancient permafrost that was submerged beneath the sea long ago and the disfiguration of the modern seafloor that occurs when released water refreezes.
After the last ice age, sea levels rose and covered the ancient permafrost on the Arctic shelf. The base of this body of ancient permafrost is slowly warming and thawing because of heat flowing out of the Earth—much older, slower climatic shifts are contributing to the melting of this Arctic submarine permafrost, not human-driven climate change. When this water migrates up to the colder seafloor, it freezes. Freezing ice pushes up ridges and mounds. Seawater seeps into the blistered seafloor surface, melting the ice layers and leaving massive sinkholes behind. The dynamic interplay between large changes in salinity and small changes in temperature near the seafloor drives this process.
The research team has published these new findings in the Journal of Geophysical Research: Earth Surface.
“Our work shows that permafrost ice is both actively forming and decomposing near the seafloor over widespread areas, creating a dynamic underwater landscape with massive sinkholes and large mounds of ice covered in sediment,” said Charlie Paull, a geologist at MBARI and the lead author of the study. “These dramatic and ongoing seafloor changes have huge implications for policymakers who are making decisions about underwater infrastructure in the Arctic.”
Since 2003, MBARI has been part of an international collaboration to study the seafloor at the edge of the Canadian Arctic shelf. This remote area that only recently became accessible to scientists as warmer temperatures caused sea ice to retreat.
A mapping survey by Canadian researchers in 2010 first uncovered the region’s distinctively rugged seafloor terrain. In 2013, MBARI researchers and their collaborators conducted the first high-resolution mapping surveys in this region. Using an MBARI autonomous underwater vehicle (AUV), the research team documented the seafloor terrain in detail.
Five mapping surveys—two conducted from Canadian research ships and three with MBARI’s advanced underwater technology—in this area over a 12-year period revealed 65 newly-formed craters on the seafloor. The largest crater was the size of a city block of six-story buildings.
In 2022, the team returned to the Arctic aboard KOPRI’s icebreaker research vessel Araon. They first used MBARI’s two seafloor mapping AUVs to identify recently formed craters. Then, they conducted visual surveys within those specific craters with MBARI’s MiniROV. This portable remotely operated vehicle developed by MBARI engineers can be configured for a variety of science missions. Equipped with cameras and sampling equipment, it has been integral to studying the Arctic seafloor. While exploring the seafloor with the MiniROV, researchers observed ice formations inside two recently formed large seafloor craters.
Isotopic analysis of these formations and samples of the surrounding seafloor sediments confirmed that the ice came from brackish groundwater, created partly by the melting ancient permafrost rising up through the seafloor. The ascending groundwaters refreeze near the seafloor, forming widespread sub-bottom ice layers that blister the seafloor, producing ice-cored mounds.
Minor temperature and salinity variations cause shifts between freezing of ascending brackish groundwater and melting of near-seafloor ice layers. These ongoing processes work in tandem to create a dramatic submarine landscape composed of numerous depressions and ice-filled mounds of varying ages.
“These findings upend our assumptions about underwater permafrost,” said Paull. “We previously believed all underwater permafrost was leftover from the last ice age, but we’ve learned that submarine permafrost ice is also actively forming and decomposing on the modern seafloor.”
The process that creates these sub-seafloor ice formations has not been considered before and may occur where bottom-water temperatures are below zero degrees Celsius.
“This discovery means that the techniques we’ve previously used to locate submarine permafrost don’t work for the types of near-seafloor ice that we recently discovered exist in the Arctic. We now need to revisit where permafrost may exist under the Arctic Shelf,” said Paull.
This work was funded by the David and Lucile Packard Foundation, the Korean Ministry of Ocean and Fisheries (KIMST grant No. 20210632), the Geological Survey of Canada, and the U.S. Naval Research Laboratory.
About MBARI
MBARI (Monterey Bay Aquarium Research Institute) is a non-profit oceanographic research center founded in 1987 by the late Silicon Valley innovator and philanthropist David Packard. Our mission is to advance marine science and technology to understand a changing ocean. Visit mbari.org to learn more.
Massive Ice Outcrops and Thermokarst Along the Arctic Shelf Edge: By-Products of Ongoing Groundwater Freezing and Thawing in the Sub-Surface
Inadequate compensation for lost or downgraded protected areas threatens global biodiversity
National University of Singapore
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The map shows the locations of terrestrial and marine protected area downgrading, downsizing, and degazettement (PADDD) events across 16 regions from 2011 to 2020. The colour-coded areas represent different types of PADDD events and compensation measures. The overlap of PADDD events and compensation efforts are highlighted in darker shades. The visualisation emphasizes the global scope of PADDD impacts and the uneven application of compensatory actions.
Conservation scientists at the National University of Singapore (NUS) have highlighted substantial gaps in the compensation for lost or downgraded protected areas. These gaps risk undermining global efforts for the protection of biodiversity and threaten the Kunming-Montreal Global Biodiversity Framework targets, which aim to conserve 30% of the planet by 2030.
The importance of protected areas
Protected areas play a crucial role in conserving biodiversity, mitigating climate change, and providing essential ecosystem services. These areas are intended for permanent protection, but since the 1900s, many protected areas have suffered downgrading, downsizing, and degazettement (PADDD) events, which expose previously protected species and ecosystems to extinction risks. Despite efforts to implement PADDD offsets and establish new protected areas, these measures often fail to fully restore lost biodiversity protection that PADDD events caused.
Research findings on PADDD compensation
The study, led by Associate Professor Roman CARRASCO from the NUS Department of Biological Sciences (NUS DBS) and Ms YAN Yanyun, who conducted the research as a Research Assistant at NUS DBS, reveals a critical shortfall in efforts to compensate for lost or downgraded protected areas via PADDD. The research team used global biodiversity data and spatial modelling to evaluate whether offsets for PADDD events, and newly established, unrelated protected areas effectively restored the integrity of the reserve networks.
The findings have been published in the journal Conservation Biology on 25 September 2024.
Assoc Prof Carrasco said, “Our results demonstrate that the loss of protected areas is not sufficiently compensated by either dedicated offsets or the creation of new protected areas. While there appears to be partial recovery in terms of area, the quality of restoration across biodiversity metrics such as for birds, mammals, amphibians and reptiles remains insufficient.”
Methodology and key insights
The study examined 16 territories (including Alaska, Australia, Bhutan, Brazil, Cambodia, Canada, Colombia, Ecuador, French Guiana, Hawaii, Mexico, Peru, South Africa, Uganda, the United Kingdom, and the United States) that experienced terrestrial PADDD events and four marine territories (including Australia, Palau, South Africa, and the United States) affected by PADDD events from 2011 to 2020. The evaluation encompassed compensation metrics such as the size of PADDD offsets, the establishment of new protected areas, and the extent of protection restored in Key Biodiversity Areas, ecoregions, and the ranges of threatened species.
Findings indicated that PADDD offsets were implemented in only 19 per cent of affected terrestrial territories and 25% of marine territories. Considering both PADDD offsets and new protected areas, the restoration of the protection was partial: 63 per cent of PADDD affected terrestrial territories have their lost area compensated, and 57% of these territories have had their Key Biodiversity Areas coverage restored. Restoration based on territories was even lower for ecoregions representation and threatened species, with only 38 per cent in ecoregions, 20 per cent in amphibians, 33 per cent in mammals, 31 per cent in birds, and 21 per cent in reptiles regaining adequate protection.
Urgent need for strategic conservation
Ms Yan said, “There is an urgent need to expand PADDD offsets and new protected areas to ensure biodiversity losses are recovered. This will allow us to meet the 30×30 target set by the Kunming-Montreal Global Biodiversity Framework with a focus on quality, not just quantity of area covered.”
“The results indicate that we are losing high quality protected areas that were critical to conserve numerous species, and we are not providing alternative protections. This leads to a degradation of protection, leaving vulnerable species increasingly exposed,” added Assoc Prof Carrasco.
The findings underscore the largely detrimental role of PADDD events and highlight the need for a more strategic approach in maintaining and designing protected area networks. To safeguard global biodiversity, it is important to focus on restoring the quality of protection alongside expanding the quantity of protected areas.
Ability of new protected areas to counteract losses from downgrading, downsizing, and degazettement
Cool roofs could have saved lives during London’s hottest summer
As many as 249 lives could have been saved in London during the 2018 record-setting hot summer had the city widely adopted cool roofs, estimates a new study by researchers at UCL and the University of Exeter.
University College London
As many as 249 lives could have been saved in London during the 2018 record-setting hot summer had the city widely adopted cool roofs, estimates a new study by researchers at UCL and the University of Exeter.
The paper, published in Nature Cities, analysed the cooling effect that roofs painted white or other reflective colours would have on London’s ambient temperature between June and August 2018, the city’s hottest summer. From June through August, the average temperature around London was 19.2 degrees C, about 1.6 degrees warmer than average for that time of year.
Urban environments tend to absorb a lot of heat and are usually a few degrees warmer than the surrounding region, an effect known as the ‘urban heat island’. Painting roofs white or reflective colours would absorb less radiant energy from the Sun than traditional dark roofs, effectively cooling the city.
The researchers found that had cool, light-coloured roofs been widely installed throughout London, it could have cooled the city by about 0.8 degrees C on average, preventing the heat-related deaths of an estimated 249 people – equating to around 32% of the 786 heat-related deaths during that period.
In the same paper, the researchers also found that had rooftop photovoltaic solar panels been similarly widely adopted, they would also have cooled the city by about 0.3 degrees C. This would have prevented the deaths of an estimated 96 people across the city, or 12% of the heat-related deaths during that summer.
The researchers used a complex 3D computer model to simulate the outcomes of different urban environments. They calculated what the average urban temperatures were during the hot 2018 summer (cross-checking it against actual measurements from the time) and then compared the temperature differences if all roofs in London were given a reflective coating, if all roofs were covered in rooftop solar panels and what the temperature of a hypothetical non-urbanised London would be.
The team also estimated the economic impact of the increased mortality rates of the two scenarios. The 96 lives saved by the adoption of rooftop solar panels would have reduced the economic burden on the city by about £237 million, while the 249 lives saved by adopting cool roofs would have reduced the city’s economic burden by about £615 million.
In addition, had rooftop solar panels been widely installed, the researchers estimate that the total electricity that could have been produced during that three-month timeframe would have been as much as 20 terawatt-hour (TWh), more than half the energy usage of London during the entire year of 2018.
Lead author, Dr Charles Simpson (UCL Bartlett School Environment, Energy & Resources) said: “If widely adopted, cool roofs can significantly reduce the ground-level air temperature of a city. The resulting cooling effect across the city would save lives and improve the quality of life for residents throughout the urban area. Solar panels have great benefits as a source of renewable power, so it’s good to see they won’t make the city hotter.”
Combating urban heat is growing in importance as the world continues to warm because of climate change. Though unusual at the time, hot summers like the one in 2018 are projected to occur more frequently because of the warming climate. In addition, the UK is particularly vulnerable to the effect as an estimated 83% of the country's population lives in urban areas.
Dr Simpson added: “As the effects of climate change manifest more and more, people living in cities will need to find new ways to adapt. Our research shows that cool roofs could be an effective way to mitigate the heat-trapping effects of urban environments.”
Co-author Professor Tim Taylor of the University of Exeter said: “The need for our cities to adapt to climate change is clear. Changing our roof spaces offers one potential solution. We need to encourage action like this, to reduce the burden of excess heat on people living in urban areas and capture potential co-benefits, including energy generation.”
Recent preliminary research by members of the team found that during the three hottest days of 2018, wide adoption of cool roofs would have lowered the city’s average temperature by about 1.2 degrees C, while rooftop solar panels would have lowered the average temperature by about 0.3 degrees C. This new research extends those modelling efforts throughout the whole summer of 2018, the hottest on record for London.
The research developed as part of the HEROIC: Health and Economic impacts of Reducing Overheating in Cities project based at UCL and Exeter, and supported by Wellcome Trust and NERC.
Notes to Editors
For more information or to speak to the researchers involved, please contact Michael Lucibella, UCL Media Relations. T: +44 (0)75 3941 0389, E: m.lucibella@ucl.ac.uk
Modelled temperature, mortality impact, and external benefits of cool roofs and rooftop photovoltaics in London, ‘Modelled temperature, mortality impact, and external benefits of cool roofs and rooftop photovoltaics in London’ will be published in Nature Cities on Tuesday 1 October 2024, 10:00 UK time 05:00 US Eastern Time, and is under a strict embargo until this time.
The DOI for this paper will be10.1038/s44284-024-00138-1.
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Modelled temperature, mortality impact, and external benefits of cool roofs and rooftop photovoltaics in London
Article Publication Date
1-Oct-2024
Reducing daily sitting may prevent back pain
University of Turku
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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.
A new study from the University of Turku in Finland showed that reducing daily sitting prevented back pain from worsening over six months. The result strengthens 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.
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.
