(Press-News.org) Each extra hour per day spent watching TV, using the internet or playing computer games during Year 10 is associated with poorer grades at GCSE at age 16, according to research from the University of Cambridge. In a study published today in the open access International Journal of Behavioral Nutrition and Physical Activity, researchers also found that pupils doing an extra hour of daily homework and reading performed significantly better than their peers. However, the level of physical activity had no effect on academic performance.
The link between physical activity and health is well established, but its link with academic achievement is not yet well understood. Similarly, although greater levels of sedentary behaviour - for example, watching TV or reading - have been linked to poorer physical health, the connection to academic achievement is also unclear.
To look at the relationship between physical activity, sedentary behaviours and academic achievement, a team of researchers led by the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge studied 845 pupils from secondary schools in Cambridgeshire and Suffolk, measuring levels of activity and sedentary behaviour at age 14.5 years and then comparing this to their performance in their GCSEs the following year. This data was from the ROOTS study, a large longitudinal study assessing health and wellbeing during adolescence led by Professor Ian Goodyer at the Developmental Psychiatry Section, Department of Psychiatry, University of Cambridge.
The researchers measured objective levels of activity and time spent sitting, through a combination of heart rate and movement sensing. Additionally the researchers used self-reported measures to assess screen time (the time spent watching TV, using the internet and playing computer games) and time spent doing homework, and reading for pleasure.
The team found that screen time was associated with total GCSE points achieved. Each additional hour per day of time spent in front of the TV or online at age 14.5 years was associated with 9.3 fewer GCSE points at age 16 years - the equivalent to two grades in one subject (for example from a B to a D) or one grade in each of two subjects, for example. Two extra hours was associated with 18 fewer points at GCSE.
Screen time and time spent reading or doing homework were independently associated with academic performance, suggesting that even if participants do a lot of reading and homework, watching TV or online activity still damages their academic performance.
The researchers found no significant association between moderate to vigorous physical activity and academic performance, though this contradicts a recent study which found a beneficial effect in some academic subjects. However, both studies conclude that engaging in physical activity does not damage a pupil's academic performance. Given the wider health and social benefits of overall physical activity, the researchers argue that it remains a public health priority both in and out of school.
As well as looking at total screen time, the researchers analysed time spent in different screen activities. Although watching TV, playing computer games or being online were all associated with poorer grades, TV viewing was found to be the most detrimental.
As this was a prospective study (in other words, the researchers followed the pupils over time to determine how different behaviours affected their academic achievement) the researchers believe they can, with some caution, infer that increased screen time led to poorer academic performance.
"Spending more time in front of a screen appears to be linked to a poorer performance at GCSE," says first author Dr Kirsten Corder from the Centre for Diet and Activity Research (CEDAR) in the MRC Epidemiology Unit at the University of Cambridge. "We only measured this behaviour in Year 10, but this is likely to be a reliable snapshot of participants' usual behaviour, so we can reasonably suggest that screen time may be damaging to a teenager' grades. Further research is needed to confirm this effect conclusively, but parents who are concerned about their child's GCSE grade might consider limiting his or her screen time."
Unsurprisingly, the researchers found that teenagers who spent their sedentary time doing homework or reading scored better at GCSE: pupils doing an extra hour of daily homework and reading achieved on average 23.1 more GCSE points than their peers. However, pupils doing over four hours of reading or homework a day performed less well than their peers - the number of pupils in this category was relatively low (only 52 participants) and may include participants who are struggling at school, and therefore do a lot of homework but unfortunately perform badly in exams.
Dr Esther van Sluijs, also from CEDAR, adds: "We believe that programmes aimed at reducing screen time could have important benefits for teenager' exam grades, as well as their health. It is also encouraging that our results show that greater physical activity does not negatively affect exam results. As physical activity has many other benefits, efforts to promote physical activity throughout the day should still be a public health priority."
INFORMATION:
The research was mainly supported by the MRC and the UK Clinical Research Collaboration.
Reference
Corder, K et al. Revising on the run or studying on the sofa: Prospective associations between physical activity, sedentary behaviour, and exam results in British adolescents. International Journal of Behavioral Nutrition and Physical Activity; 4 Sept 2015.
Metabolic or bariatric surgery may be more effective than standard medical treatments for the long-term control of type 2 diabetes in obese patients, according to a new study by King's College London and the Universita Cattolica in Rome, Italy. The study, published in the Lancet, is the first to provide data on five-year outcomes of surgery from a randomized clinical trial specifically designed to compare this new approach against standard medical therapy for the treatment of type 2 diabetes.
A number of studies have shown that bariatric or weight-loss surgery can result ...
Astronomers from the University of Cambridge have developed a new, highly accurate method of measuring the distances between stars, which could be used to measure the size of the galaxy, enabling greater understanding of how it evolved.
Using a technique which searches out stellar 'twins', the researchers have been able to measure distances between stars with far greater precision than is possible using typical model-dependent methods. The technique could be a valuable complement to the Gaia satellite - which is creating a three-dimensional map of the sky over five years ...
Many doctors working in India's private hospitals are under pressure to carry out unnecessary tests and procedures to meet revenue targets, according to The BMJ this week.
In a special report published today, Meera Kay, a journalist in Bangalore, asks what can be done about financial targets for doctors working in profit driven hospitals that lead to expensive but unnecessary tests and surgery that also come with risk of harm?
According to Dr Gautam Mistry, a cardiologist in Kolkata, such unethical practices are widely known about in medical circles but public discourse ...
Among 51 military service members who experienced severe acute kidney injury during the Iraq and Afghanistan wars, 88% of the injuries were due to blasts or projectiles.
Twenty-two percent of the patients died within 60 days. Although still high, this mortality rate is significantly less than might be expected historically.
The majority of survivors completely recovered their kidney function.
Washington, DC (September 3, 2015) -- Acute kidney injury (AKI) leading to an abrupt or rapid decline in kidney function is a serious and increasingly prevalent condition. While ...
COLUMBUS, Ohio - Using a new technique to analyze 52 years of international conflict, researchers suggest that there may be no such thing as a "democratic peace."
In addition, a model developed with this new technique was found to predict international conflict five and even ten years in the future better than any existing model.
Democratic peace is the widely held theory that democracies are less likely to go to war against each other than countries with other types of government.
In the new study, researchers found that economic trade relationships and participation ...
Researchers at University of California, San Diego School of Medicine have documented the accuracy of three new tests for more rapidly diagnosing drug-resistant forms of tuberculosis (TB), which are much harder and more expensive to treat and which, experts say, represent a major threat to global public health.
The study is published online in the current issue of PLOS ONE.
"Our study shows that TB testing that once took two to three months can now be done in as little as a day," said co-author Richard Garfein, PhD, professor in the Division of Global Public Health ...
Earth's species are disappearing at an astonishing--and troubling--rate. As human activity continues to put pressure on ecosystems around the world, the rate of loss continues to climb. How we slow this devastating loss and protect the enormous number of species on Earth is of considerable importance, and debate.
Unfortunately, it is not feasible to simply protect everything. Limited funds require conservation planners and policy makers to prioritize the preservation of specific regions and ecosystems. An often-used strategy is to identify areas of high species richness ...
September 3, 2015 - Men and women exposed in early gestation to the man-made Ukrainian Famine of 1932-33 in regions with extreme food shortages were 1.5 times more likely to be diagnosed with Type 2 diabetes in adulthood. In regions with severe famine there was a 1.3 fold rise in the odds of Type 2 diabetes, and there was no diabetes increase among individuals born in regions with no famine.
Researchers at Columbia University's Mailman School of Public Health, the Komisarenko Institute of Endocrinology and Metabolism in Kiev, Ukraine, and the Cheboratev Institute of Gerontology ...
MADISON, Wis. -- "Gaydar" -- the purported ability to infer whether people are gay or straight based on their appearance -- seemed to get a scientific boost from a 2008 study that concluded people could accurately guess someone's sexual orientation based on photographs of their faces.
In a new paper published in the Journal of Sex Research, researchers at the University of Wisconsin-Madison challenge what they call "the gaydar myth." William Cox, an assistant scientist in the Department of Psychology and the lead author, says gaydar isn't accurate and is actually a harmful ...
The gut is an important reservoir for drug-resistant bacteria responsible for life-threatening hospital-acquired infections. A study in mice published on September 3rd in PLOS Pathogens reports that two of the most common antibiotic-resistant bacterial species circulating in hospitals occupy and effectively share the same location in the gut, and that they can be eliminated by fecal transplantation of a healthy gut microbiome.
Eric Pamer, from Memorial Sloan-Kettering Cancer Center in New York, USA, and colleagues, investigated the interactions between vancomycin-resistant ...
