(Press-News.org) ATLANTA – July 14, 2014 –Physical fitness may buffer some of the adverse health effects of too much sitting, according to a new study by researchers from the American Cancer Society, The Cooper Institute, and the University of Texas. The study appears in the journal Mayo Clinic Proceedings, and finds the association between prolonged sedentary time and obesity and blood markers associated with cardiovascular disease is markedly less pronounced when taking fitness into account.
Sedentary behavior has been linked to an increase risk of obesity, metabolic syndrome, type 2 diabetes mellitus, cardiovascular disease, some cancers, and premature death. But previous studies of the association have not taken into account the protective impact of fitness, a strong predictor of cardiovascular disease incidence and mortality.
For the current study, researchers led by Kerem Shuval, Ph.D., of the American Cancer Society, examined the association of sedentary behavior, physical activity, and fitness to obesity and metabolic biomarkers among 1304 men seen at the Cooper Clinic in Dallas, Texas between 1981 and 2012. Sedentary time was composed of self-reported television viewing time and time spent in a car self-reported on a 1982 survey. Fitness was determined by a treadmill test during the medical examination at clinic visits.
The study showed that more sedentary time was significantly associated with higher levels of systolic blood pressure, and total cholesterol and triglycerides, as well as lower levels of HDL, the "good" cholesterol. It was also associated with BMI, waist circumference, and body fat percentage. But when researchers controlled for fitness, they found prolonged sedentary time was only significantly associated with a higher triglyceride/HDL cholesterol ratio (an indicator of insulin resistance). Sedentary time was not associated with metabolic syndrome (a clustering of risk factors). In comparison, higher fitness levels were associated with reduced adiposity and metabolic measures.
The authors say interpretation of their study's findings should be tempered by its limitations. For example, sedentary behavior was based on self-report at one point in time, whereas fitness was assessed objectively during clinic visits.
"[A]lthough our findings suggest the need to encourage achieving higher levels of fitness through meeting physical activity guidelines to decrease metabolic risk," they conclude, "the effects of reducing sedentary time on cardiometabolic risk biomarkers warrant further longitudinal exploration using objective measurement."
INFORMATION:
Additional co-authors on the study include: Carrie E. Finley, Carolyn E. Barlow, and Dr. David Leonard (Cooper Institute), and Drs. Kelley Pettee Gabriel and Harold W. Kohl III (University of Texas School of Public Health).
Article: Sedentary Behavior, Cardiorespiratory Fitness, Physical Activity, and Cardiometabolic Risk in Men: The Cooper Center Longitudinal Study Mayo Clin Proc. 2014 Published ahead of print July 14 2014
Physical fitness associated with less pronounced effect of sedentary behavior
2014-07-14
ELSE PRESS RELEASES FROM THIS DATE:
Domestication syndrome: White patches, baby faces and tameness
2014-07-14
More than 140 years ago, Charles Darwin noticed something peculiar about domesticated mammals. Compared to their wild ancestors, domestic species are more tame, and they also tend to display a suite of other characteristic features, including floppier ears, patches of white fur, and more juvenile faces with smaller jaws. Since Darwin's observations, the explanation for this pattern has proved elusive, but now, in a Perspectives article published in the journal GENETICS, a new hypothesis has been proposed that could explain why breeding for tameness causes changes in such ...
UEA research reveals how cannabis compound could slow tumour growth
2014-07-14
Scientists at the University of East Anglia have shown how the main psychoactive ingredient in cannabis could reduce tumor growth in cancer patients.
Research published today reveals the existence of previously unknown signaling platforms which are responsible for the drug's success in shrinking tumours.
It is hoped that the findings could help develop a synthetic equivalent with anti-cancer properties.
The research was co-led with the Universidad Complutense de Madridin, Spain. The team used samples of human breast cancer cells to induce tumours in mice. They ...
The world's first photonic router
2014-07-14
Weizmann Institute scientists have demonstrated for the first time a photonic router – a quantum device based on a single atom that enables routing of single photons by single photons. This achievement, as reported in Science magazine, is another step toward overcoming the difficulties in building quantum computers.
At the core of the device is an atom that can switch between two states. The state is set just by sending a single particle of light – or photon – from the right or the left via an optical fiber. The atom, in response, then reflects or transmits the next incoming ...
Serendipity at the Smithsonian: The 107-year journey of the beetle Rhipidocyrtus muiri
2014-07-14
Serendipity leads University of Kansas scientists to the discovery and description of Rhipidocyrtus muiri - a 107 year old, lost in collections specimen, which turned out to represent a new genus and species. The long and tortuous history of the enigmatic ripidiine wedge beetle from Borneo is discussed in a recent paper published in the open access journal ZooKeys.
The holotype male, and only known specimen of Rhipidocyrtus muiri, was collected 107 years ago in Borneo but subsequent to this it was transferred among several researchers in the early 1900s. The specimen ...
Best for bees to be stay-at-homes
2014-07-14
Honey bees with roots in the local environment manage much better in the struggle for survival than imported honey bees from foreign environments.
A world without bees would be a whole lot poorer – literally. In Denmark alone an additional 600 million to 1 billion Danish kroner are earned annually due to the work done by bees making honey and pollinating a wide range of crops from apples to cherries and clover.
Unfortunately, bees all over the world are under pressure from pesticides, mites, viruses, bacteria, fungi and environmental changes, among other things. The ...
Molecular mechanisms underlying the prevention of autoim-munity by Roquin revealed
2014-07-14
The Roquin protein, discovered in 2005, controls T-cell activation and differentiation by regulating the expression of certain mRNAs. In doing so, it helps to guarantee immunological tolerance and prevents immune responses against the body's own structures that can lead to autoimmune disease. Roquin is thus an immune regulator. Autoimmune diseases affect between five and ten per cent of the population. They usually occur as a result of complex environmental influences when a genetic predisposition exists. Only in rare cases the development of the disease is determined by ...
Flower development in 3D: Timing is the key
2014-07-14
In close collaboration with Jürg Schönenberger and Yannick Städler from the Department of Botany and Biodiversity Research of the Faculty of Life Sciences, University of Vienna, 14 developmental stages of the flower of Arabidopsis thaliana from very early meristematic floral initiation to fully developed seeds were monitored with micro-computed tomography in 3D. From the same set of developmental stages a full metabolic profile using mass spectrometry was measured covering hundreds of biochemical pathways.
"Smallest changes in floral organ development were thus correlated ...
A-maize-ing double life of a genome
2014-07-14
Early maize farmers selected for genes that improved the harvesting of sunlight, a new detailed study of how plants use 'doubles' of their genomes reveals. The findings could help current efforts to improve existing crop varieties.
Oxford University researchers captured a 'genetic snapshot' of maize as it existed 10 million years ago when the plant made a double of its genome – a 'whole genome duplication' event. They then traced how maize evolved to use these 'copied' genes to cope with the pressures of domestication, which began around 12,000 years ago. They discovered ...
Rutgers chemists develop technology to produce clean-burning hydrogen fuel
2014-07-14
Rutgers researchers have developed a technology that could overcome a major cost barrier to make clean-burning hydrogen fuel – a fuel that could replace expensive and environmentally harmful fossil fuels.
The new technology is a novel catalyst that performs almost as well as cost-prohibitive platinum for so-called electrolysis reactions, which use electric currents to split water molecules into hydrogen and oxygen. The Rutgers technology is also far more efficient than less-expensive catalysts investigated to-date.
"Hydrogen has long been expected to play a vital role ...
Wisconsin scientists find genetic recipe to turn stem cells to blood
2014-07-14
MADISON, Wis. — The ability to reliably and safely make in the laboratory all of the different types of cells in human blood is one key step closer to reality.
Writing today in the journal Nature Communications, a group led by University of Wisconsin-Madison stem cell researcher Igor Slukvin reports the discovery of two genetic programs responsible for taking blank-slate stem cells and turning them into both red and the array of white cells that make up human blood.
The research is important because it identifies how nature itself makes blood products at the earliest ...