Thursday, 26 December 2013

Another cell study spun as 'age-reversing miracle' - NAD+

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Links (accessed 26th December 2013)

Cell Journal
Declining NAD+ Induces a Pseudohypoxic State Disrupting Nuclear-Mitochondrial Communication during Aging

A New—and Reversible—Cause of Aging
A naturally produced compound rewinds aspects of age-related demise in mice
December 19, 2013
Mitochondria, organelles on the right, interact with the cell's nucleus to ensure a healthy, functioning cell. Image by Ana GomesMitochondria, organelles on the right, interact with the cell's nucleus to ensure a healthy, functioning cell. Image by Ana Gomes

Researchers have discovered a cause of aging in mammals that may be reversible.
The essence of this finding is a series of molecular events that enable communication inside cells between the nucleus and mitochondria. As communication breaks down, aging accelerates. By administering a molecule naturally produced by the human body, scientists restored the communication network in older mice. Subsequent tissue samples showed key biological hallmarks that were comparable to those of much younger animals.
“The aging process we discovered is like a married couple—when they are young, they communicate well, but over time, living in close quarters for many years, communication breaks down,” said Harvard Medical School Professor of Genetics David Sinclair, senior author on the study. “And just like with a couple, restoring communication solved the problem.”
This study was a joint project between Harvard Medical School, the National Institute on Aging, and the University of New South Wales, Sydney, Australia, where Sinclair also holds a position.
The findings are published Dec. 19 in Cell.
Communication breakdown
Mitochondria are often referred to as the cell's "powerhouse," generating chemical energy to carry out essential biological functions. These self-contained organelles, which live inside our cells and house their own small genomes, have long been identified as key biological players in aging. As they become increasingly dysfunctional overtime, many age-related conditions such as Alzheimer’s disease and diabetes gradually set in.
Researchers have generally been skeptical of the idea that aging can be reversed, due mainly to the prevailing theory that age-related ills are the result of mutations in mitochondrial DNA—and mutations cannot be reversed.
Sinclair and his group have been studying the fundamental science of aging—which is broadly defined as the gradual decline in function with time—for many years, primarily focusing on a group of genes called sirtuins. Previous studies from his lab showed that one of these genes, SIRT1, was activated by the compound resveratrol, which is found in grapes, red wine and certain nuts.
Sirt1 protein, red, circles the cell's chromosomes, blue. Image by Ana GomesSirt1 protein, red, circles the cell's chromosomes, blue. Image by Ana GomesAna Gomes, a postdoctoral scientist in the Sinclair lab, had been studying mice in which thisSIRT1 gene had been removed. While they accurately predicted that these mice would show signs of aging, including mitochondrial dysfunction, the researchers were surprised to find that most mitochondrial proteins coming from the cell’s nucleus were at normal levels; only those encoded by the mitochondrial genome were reduced.
“This was at odds with what the literature suggested,” said Gomes.
As Gomes and her colleagues investigated potential causes for this, they discovered an intricate cascade of events that begins with a chemical called NAD and concludes with a key molecule that shuttles information and coordinates activities between the cell’s nuclear genome and the mitochondrial genome. Cells stay healthy as long as coordination between the genomes remains fluid. SIRT1’s role is intermediary, akin to a security guard; it assures that a meddlesome molecule called HIF-1 does not interfere with communication.
For reasons still unclear, as we age, levels of the initial chemical NAD decline. Without sufficient NAD, SIRT1 loses its ability to keep tabs on HIF-1. Levels of HIF-1 escalate and begin wreaking havoc on the otherwise smooth cross-genome communication. Over time, the research team found, this loss of communication reduces the cell's ability to make energy, and signs of aging and disease become apparent.
“This particular component of the aging process had never before been described,” said Gomes.
While the breakdown of this process causes a rapid decline in mitochondrial function, other signs of aging take longer to occur. Gomes found that by administering an endogenous compound that cells transform into NAD, she could repair the broken network and rapidly restore communication and mitochondrial function. If the compound was given early enough—prior to excessive mutation accumulation—within days, some aspects of the aging process could be reversed.
When Sirt1 loses its ability to monitor HIF-1, communication between mitochondria and the nucleus breaks down, and aging accelerates. Image by Ana GomesWhen Sirt1 loses its ability to monitor HIF-1, communication between mitochondria and the nucleus breaks down, and aging accelerates. Image by Ana Gomes
Cancer connection
Examining muscle from two-year-old mice that had been given the NAD-producing compound for just one week, the researchers looked for indicators of insulin resistance, inflammation and muscle wasting. In all three instances, tissue from the mice resembled that of six-month-old mice. In human years, this would be like a 60-year-old converting to a 20-year-old in these specific areas.
One particularly important aspect of this finding involvesHIF-1. More than just an intrusive molecule that foils communication, HIF-1 normally switches on when the body is deprived of oxygen. Otherwise, it remains silent. Cancer, however, is known to activate and hijack HIF-1. Researchers have been investigating the precise role HIF-1 plays in cancer growth.
“It’s certainly significant to find that a molecule that switches on in many cancers also switches on during aging,” said Gomes. “We're starting to see now that the physiology of cancer is in certain ways similar to the physiology of aging. Perhaps this can explain why the greatest risk of cancer is age.”
“There’s clearly much more work to be done here, but if these results stand, then certain aspects of aging may be reversible if caught early,” said Sinclair.
The researchers are now looking at the longer-term outcomes of the NAD-producing compound in mice and how it affects the mouse as a whole. They are also exploring whether the compound can be used to safely treat rare mitochondrial diseases or more common diseases such as Type 1 and Type 2 diabetes. Longer term, Sinclair plans to test if the compound will give mice a healthier, longer life.
The Sinclair lab is funded by the National Institute on Aging (NIA/NIH), the Glenn Foundation for Medical Research, the Juvenile Diabetes Research Foundation, the United Mitochondrial Disease Foundation and a gift from the Schulak family.

Wednesday, 27 November 2013

Aspirin at bedtime 'cuts' morning heart attack risk

Aspirin at bedtime 'cuts' morning heart attack risk - Health News - NHS Choices

“Take aspirin before bed to cut morning heart risk,” is the advice in The Daily Telegraph today. It’s prompted by a presentation that explained research that found a night-time aspirin helped thin the blood in the morning.

The researchers randomised 290 people who were already taking low-dose aspirin to make the blood less "sticky" for the prevention of cardiovascular disease (CVD) either to take aspirin in the morning or at bedtime. ... more

Wednesday, 20 November 2013

Vaccination 'a civic duty' according to new report - Health News - NHS Choices

Vaccination 'a civic duty' according to new report - Health News - NHS Choices

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crabsallover highlightskey pointscomments / links.

We know little about the effect of diet on health. That’s why so much is written about it

DC's Improbable Science: Truth, falsehood and evidence: investigations of dubious and dishonest science says:-

"The question of what to eat for good health is truly a topic about "which so much has been talked and so little can be said"That was emphasized yet again by an editorial in the Brirish Medical Journal written by my favourite epidemiologist. John Ioannidis. He has been at the forefront of debunking hype. Its title is “Implausible results in human nutrition research” (BMJ, 2013;347:f6698.
Get pdf
Get pdf)."

Thursday, 14 November 2013

Weight loss could affect the way couples interact

reposted from:
crabsallover highlightskey pointscomments / links.

“How losing weight can be bad for your relationship, with partners sabotaging diets and rejecting sex,” reports the Mail Online. Though the study it reports on also found weight loss brought many couples closer together.
The study researched an often overlooked issue. That is the impact weight loss may have on a relationship; especially if one partner loses weight while the other remains overweight or obese.
This US study used online questionnaires to investigate behaviours and communication among 21 couples where one person in the couple had recently lost 14 kilograms or more.
The researchers found weight loss could have both positive and negative effects on a relationship, centred around two main themes.
The first theme was termed “heightened communication about weight management”. On the positive side some participants reported that their partner losing weight inspired them to do the same. On the negative side some participants reported resentment about being nagged to lose weight. 
The second theme was termed "changes in intimacy”. While most couples reported becoming closer, some participants reported feeling insecure that their partner had lost weight.
Although this study provides some interesting insights, we cannot assume that its findings will apply to everyone.
It does, however, highlight the fact that weight loss can sometimes have a significant effect on a relationship, be it good or bad. It is something you may wish to discuss with your partner if you are planning to lose weight.
And maybe you could try to lose weight together?

Where did the story come from?

The study was carried out by researchers from North Carolina State University and the University of Texas at Austin in the US. Sources of funding were not reported. The study was published in the peer-reviewed journal Health Communication.
The Mail Online’s reporting of the study mainly focused on the negative findings – which is unsurprising, bad news sells more than good news. Its headline “How losing weight can be bad for your relationship, with partners sabotaging diets and rejecting sex” is not representative of the main finding of the study. Many couples reported that weight loss had a positive effect on their relationship.
Its actual reporting of the study is more representative, though it does not include the researchers’ conclusions that the study findings are not generalisable.

What kind of research was this?

This was a qualitative study looking at how weight loss can affect communication and behaviour in romantic relationships. Specifically the researchers were interested in examining perceptions of how weight loss had an effect on communication and behaviour between a couple, where one person had lost weight and the other had not.
Qualitative studies can provide useful insights at an individual level but these insights should never be assumed to be some sort of universal truth. For example, a similar study involving Indigenous Australian people could come up with entirely different responses.

What did the research involve?

The study included 42 adults (21 ‘romantic’ couples) based across the US, in which one partner had lost 30 pounds (approximately 14 kilograms) or more in the two years prior to the study. There were no restrictions placed on how the person had lost weight, for example this could have been through weight loss programs, surgery, dieting and /or exercise, however women who had lost the weight following pregnancy were not included.
The researchers say the couples did not have to be married or heterosexual (in a male/female relationship), but had to have been together before the weight loss occurred and be living together at the time of the study.
The couples were recruited through various sources, including word of mouth, postings on weight-loss blogs and weight-loss surgery support groups.
The participants were asked to complete separate online questionnaires – one questionnaire for those that had lost weight and a separate questionnaire for those that had not lost weight. Online questionnaires were reported to be chosen due to being less threatening than face-to-face interviews. They were asked not to consult their partner when completing the questionnaire.
The questionnaire included a series of 30 open ended questions. The exact questions are not provided by the researchers, but they say participants were asked:
  • about their interaction with one another about weight management before and after one of the partner’s weight loss
  • to describe the consequences of weight loss on their own health or their partner’s health, and the extent to which this surprised them
  • to share any additional information about the effects of the weight loss
  • about the person’s sex, age, height, weight and length of relationship 
Following completion of the questionnaires, each participant received a US$10 gift card to use at a food chain or one of two national businesses (actual businesses not reported).
The two researchers then used qualitative methods to analyse the results and grouped answers into themes where topics or phrases were repeated.

What were the basic results?

The age of the participants ranged from 20 to 61 years, the length of relationship ranged from 2 to 33 years, and the majority of the participants were white (88%). Thebody mass index (BMI) for non-weight loss participants ranged from 17.7 (considered underweight) to 34.6 (considered obese). The BMI for the participants who lost weight (after weight loss) ranged from 19.5 (considered normal weight) to 48.0.
The researchers say the study showed weight loss can result in both beneficial and negative interactions. They report that two main themes emerged from the analysis, which are described briefly below.

Theme 1: ‘Heightened communication about weight management’

Many of the partners of the person who had lost the weight perceived communication about weight management to have been limited or ineffective prior to the weight loss. After losing weight, many of the participants perceived it was common for the person who lost the weight to talk more about their weight management and to encourage and inspire family members to lead a healthy lifestyle.

The researchers also found that some participants who had lost weight went ‘from pudgy to pestering’ and nagged their partners to follow their lead and lose weight.

Theme 2: ‘Changes in intimacy’

Following weight loss, participants commonly perceived their intimacy levels to change, which was reflected in their communication. The researchers say most couples said their interaction had become more positive and that they had become physically and emotionally closer, such as a strengthened sexual relationship.

However, they said some participants reported negative behaviours such as criticism and insecure comments from partners who had not lost weight, such as participants who had not lost weight feeling negative about themselves for not also losing weight. Another negative finding the researchers reported was that two participants who had lost weight felt more assertive which prompted them to exhibit ‘potentially relationship-disrupting behaviours’.

How did the researchers interpret the results?

The researchers concluded that while losing weight resulted in positive interaction for many partners (such as engaging in a shared healthy lifestyle), shedding weight also led to some negative consequences (for example non-weight-loss partner criticism). They say the extent to which partners embraced new weight management rules and patterns influenced post-weight-loss communication and behaviour.
The Mail Online quotes Dr Romo, one of the researchers, as saying: “This study found that one partner’s lifestyle change influenced the dynamic of couples’ interaction in a variety of positive or negative ways, tipping the scale of romantic relationships in a potentially upward or downward direction.”


The interesting nature of this study provides some insights into the effects of weight loss on relationships, though limited conclusions can be drawn about the strength of any effect on behaviours and communication from this qualitative research.
It is common for qualitative research to include smaller numbers, this study only included 21 couples, all based in the US, so asking the same questions to a different group of people from different ethnicities or countries may result in different answers.
Furthermore, the researchers say that as online questionnaires were used, this may have excluded groups without internet access, such as those with lower incomes or elderly people from participating in the study. As the study only included couples where one person had lost weight, the findings do not apply to couples in which both people have lost weight or are trying to maintain weight loss. 
The researchers do note that although their findings provide an understanding of how and why weight loss can affect couples’ post weight-loss interactions, the findings are not generalisable, possibly due to the reasons pointed out above, although they do not explain their exact reasoning.
To draw firmer conclusions about the effects on behaviour after one person in a couple loses a substantial amount of weight, larger studies with more diverse populations are required.   
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Links To Science

Romo LK, Dailey RM. Weighty Dynamics: Exploring Couples' Perceptions of Post-Weight-Loss Interaction. Health Communication. Published online October 24 2013

Did scientists over-hype swine flu?

"Swine flu risk was inflated by experts with links to drugs industry," The Independent reports. The claim has been made by the authors of a study that analysed newspaper reporting of the swine flu pandemic in 2009.
Researchers found that academics with industry links were six times more likely to rate the potential risk of swine flu as higher.
Similarly, academics promoting the use of antiviral drugs in newspaper articles were eight times more likely to have industry links than those not commenting on their use.
This is not to say that there is any evidence of wrongdoing. If there was a bias in some academics' analysis, it could well be unconscious. If you have spent your career working with antivirals, it is only natural to discuss them when interviewed. It should also be noted that the findings of this study are based on a small sample of articles.
However, the findings do suggest some evidence of industry influence on the discussion of important public health issues. These articles appeared at a time when the government was making important decisions about antiviral medications. The UK government went on to spend more than £400 million on a stockpile of antivirals.
It is important that journalists don't assume that all academics are coming from a neutral position. Similarly, in the interests of transparency academics should make any potential conflicts of interest clear.
Both actions would help improve public trust in the pharmaceutical industry, academics, journalists and policymakers.

Where did the story come from?

The study was carried out by researchers from the London School of Hygiene and Tropical Medicine, Imperial College London, Princess Alexandra Hospital NHS Trust, Harlow, Chase Farm Hospital, Enfield, City University London, and The London School of Medicine & Dentistry. The lead author is funded by the Wellcome Trust, a charitable health foundation.
It was published in the peer-reviewed Journal of Epidemiology and Community Health. It has been made available on an open access basis, so it is free to read online or download.
The study was covered fairly by The Independent.

What kind of research was this?

This was a retrospective analysis of UK newspaper articles on swine (A/H1N1) flu, examining the sources quoted by journalists.
In particular, researchers looked at whether academics who had been quoted in the media had any links to the drug industry.
The researchers also looked for articles about the use of antiviral drugs for swine flu – the best known of which is Tamiflu – or vaccines against flu.
The researchers point out that the UK spent an estimated billion pounds on pharmaceutical products during the 2009-10 swine flu pandemic, including antiviral medications and swine flu vaccines. This was despite the subsequent evaluation that the pandemic was less severe than previous pandemics.
There was also uncertainty about the effectiveness of antiviral medication in reducing transmission and complications of influenza. Some dissenting voices argued that the limited benefit of medications such as Tamiflu did not justify their costs.
The researchers go on to explain that after the pandemic passed in 2010, there were significant concerns that several of the experts on influential committees advising the government had competing interests, including links to the manufacturers of antiviral drugs and influenza vaccines.
There have been repeated calls for greater transparency around the potential influence of the pharmaceutical industry on the decisions made by these committees, they say.
The researchers also point out that public health academics are often asked to provide commentary and analysis on emerging health risks by the media. Media coverage of health issues has been shown to influence the public's perception of risk, demand for new drugs and policy decisions, they argue.
Like those on advisory committees, academics quoted in the media may also have possible conflicts of interest. Media commentaries, they argue, provide, "an alternative route to exert pressure on public demand", and one in which conflicts of interest are not routinely declared.

What did the research involve?

The researchers set out to examine media commentary on swine flu provided by academics between April and July 2009. This was the period in which the UK government was deciding its policy on the public provision of antiviral medication and the swine flu vaccine.
The researchers searched for newspaper articles about swine flu using a database providing full access to all UK national newspapers. Twelve UK national newspapers were included in the sample, including daily, Sunday, tabloid, middle-market and broadsheet publications on both sides of the political spectrum. They excluded TV and radio coverage on the grounds that broadcast media offers less in-depth analysis and less divergent viewpoints than print media.
Using these criteria, the researchers included 425 articles in their study. Each article was assessed independently by two of the authors using a standardised coding framework consisting of two sections.
The first section categorised the sources quoted in each article, such as:
  • health ministers (England, Wales, Scotland and Northern Ireland)
  • Department of Health (England Wales, Scotland and Northern Ireland)
  • Chief Medical Officer (England Wales, Scotland and Northern Ireland)
  • World Health Organization (WHO)
  • the UK Health Protection Agency (HPA)
  • the US Centers for Disease Prevention and Control (CDC)
  • pharmaceutical company representatives
  • named academics (defined here as a researcher or academic clinician affiliated with a higher educational body or research institute)
The second section looked in greater detail at those articles that quoted academic sources. The researchers first examined whether academics made a risk assessment of the emerging pandemic. For example, quotes such as, "this is going to affect millions of people in England" or "thousands of people could die from this virus" would constitute a risk assessment.
They then checked whether the academic cited official figures or whether there was a risk assessment made by an official body relevant to the UK population quoted within the same article, such as the WHO, the Health Secretary, or the Department of Health.
They used the official risk assessments as a benchmark to measure each academic risk assessment, judging whether it concurred with the official estimate or was higher or lower (implying more or less risk to the public).
The researchers also examined all quotes by academics for reference to the use of medication for swine flu or the influenza vaccine. Those that made reference to the drugs or the vaccine were further analysed as to whether they promoted or rejected the use of these products.
The researchers piloted this method of coding on 20 articles, with subsequent minor modifications made to definitions before coding the complete data set.
They then looked at evidence of conflicts of interest for each named academic quoted, using the protocol from a recent study. 
According to guidelines, conflicts of interest are defined as when an author has financial or personal relationships that could inappropriately influence (bias) his or her actions.
For each academic, the researchers looked for associations with pharmaceutical or biotechnology companies in the form of grants (including research), honorariums, speaker fees, consultant, adviser or employee relationships, and stock ownership.
These could be personal, indicating benefits for that individual – such as honorariums – or non-personal, indicating benefits for a department or organisation for which an academic has managerial responsibility, such as research grants.
The researchers searched for conflicts of interest from the four years before the start of the pandemic. This is in line with guidelines that state that conflicts of interest should be declared if incurred in the four years before acting in an expert advisory role.
They did this by searching for:
  • conflict of interest statements (where available) for four major scientific advisory committees relevant to this issue
  • funding sources detailed on the individual's profile page on the website of the affiliated institution
  • a general internet search using Google
  • conflict of interest and funding declarations on all publications in the past four years identified through the PubMed/Medline database
They then calculated the likelihood of a risk assessment being higher than official estimates if it was made by an academic with a conflict of interest, compared with those who did not have a conflict of interest.
They also calculated the likelihood of an academic who promoted or rejected the use of antiviral drugs or vaccines for swine flu having a conflict of interest, compared with academics who provided general commentary.

What were the basic results?

Below are the main findings:
  • in the newspaper articles studied, academics were the second most frequently quoted source after health ministers
  • where both academics and official agencies estimated the risk of swine flu, one in two academics assessed the risk as higher than official predictions
  • for academics with conflicts of interest, the odds of a higher risk assessment were 5.8 times greater than those made by academics without conflicts of interest
  • half of academics commenting on the use of antiviral medications or vaccine for swine flu had conflicts of interest
  • the odds of conflicts of interest in academics promoting the use of antiviral medications were 8.4 times greater than for academics not commenting on their use
  • only three articles out of 425 mentioned that the academic quoted had a potential competing interest

How did the researchers interpret the results?

The researchers say there is evidence of conflicts of interest among academics providing media commentary during the early swine flu pandemic, a period critical for policy making on drugs and vaccines. Heightened risk assessments, combined with advocacy for pharmaceutical products to counter this risk, may lead to increased public anxiety and demand, they say.
"These add to the growing body of literature highlighting the potential influence of the pharmaceutical industry on policy decisions through multiple avenues, including advisory committees, drafting of guidelines, and media commentary," they note. "Academics should declare, and journalists report, relevant [competing interests] for media interviews."
Commenting on the research, the journal's editors add: "This paper clearly shows that 'scientific advice' is not necessarily independent and that it is influenced by often undisclosed interests."


This was a well-conducted study, albeit based on a small sample of articles. The finding that academics with ties to the drugs industry were more likely to make a higher assessment of risk from swine flu, and those promoting the use of antiviral drugs were more likely to have industry links, is worrying.
The general issue of academics with undisclosed links to the pharmaceutical industry being interviewed by journalists is of concern. That said, the study does not prove that media coverage either fuelled public anxiety about swine flu or the policy decisions made about drug or vaccine funding.
Similarly, there is no evidence of any wrongdoing by any of the academics identified in the study.
However, the result does highlight the worrying trend that journalists take the claims made by experts at face value in a way that they might not with politicians, for example.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. 

Links To The Headlines

Links To Science

Mandeville KL, O'Neill S, Brighouse A, et al. Academics and competing interests in H1N1 influenza media reporting. Journal of Epidemiology and Community Health. Published online November 11 2013

Tuesday, 5 November 2013

Is sex better exercise than walking?

reposted from:
crabsallover highlightskey pointscomments / links.

“Forget going for a stroll – try sexercise: Average session burns more calories than a walk – but less than a jog,” reads today’s Mail Online.
The idea that sex can help burn off calories has long been a staple of magazines and daytime chat shows. In fact, no-one has accurately measured how many calories are expended during sex.
The current research attempted to fill this research void by recruiting 21 young couples whose energy expenditure during sex was measured and compared with 30 minutes of moderate intensity on a treadmill.
So did sex match the treadmill in terms of energy expenditure? The short answer is no, at least not in this small and strictly defined group.
The researchers found the energy expenditure of sexual activity was significantly less than expended during the 30 minutes of treadmill exercise – around two-thirds less. For example, men’s average energy expenditure during sexual activity was 101 calories but 276 calories on the treadmill.
However, as the researchers put it “almost all of the participants reported that sexual activity was more pleasant than the treadmill exercise" – so sex seems to have an upside.

Where did the story come from?

The study was carried out by researchers from universities based in Quebec, Canada and was funded by grants from The Foundation for the Scientific Study of Sexuality and l’Institut Santé et Société of the Université du Québec à Montréal.
The study was published in the peer-reviewed science journal PLOS ONE. The article was open-access, meaning it is free to access online or download.
The Mail Online coverage was generally accurate, however the statement that an “average session burns more calories than a walk – but less than a jog” is based on a series of assumptions, for example, how long would the jog last, rather than being tested directly.

What kind of research was this?

This experimental study looked at the energy expenditure during sexual activity in young healthy couples in their natural environment and compared it to moderate exercise.
Why you might want to investigate this from a medical point of view is perhaps less obvious. The authors describe how health professionals are beginning to recognise that sexual activity could have an important influence on overall health and quality of life. The rationale seemed to be aimed at getting a better idea of the extent to which sex was or could contribute to recommended levels of physical activity in young people, and how it measured up to other activities like jogging.

What did the research involve?

Twenty-one heterosexual couples from the Montreal region of Canada were recruited to the study between September 2012 and April 2013.
Participants were only included if:
  • they were aged between 18-35 years old
  • they were born in the province of Quebec and French speaking
  • they were Caucasian
  • they were non-sedentary (did more than two hours a week of structured exercise)
  • they had no sexual dysfunctions – i.e. premature ejaculation or erectile dysfunction
  • be sexually active (at least one sexual activity per week)
  • they were in a loving, monogamous and stable relationship with their partner for a duration of between six and 24 months
  • the women in the partnership were using oral contraception
All participants also reported no cardiovascular diseases, diabetes or any orthopaedic limitations, such as problems with bones or joints.
All participants completed one endurance exercise session at the start of the study which consisted of a five-minute warm-up (walking) followed by 30 minutes of exercise on a treadmill at moderate intensity. The goal, the authors reported, was to use an exercise that could be regularly practised by the general population to act as an activity to compare sex against.
Exercising a minimum five times per week for 30 minutes at moderate intensity is also the amount the general population are recommended to engage in to help maintain a healthy lifestyle – a total of at least 150 minutes per week.
Energy expenditure (measured in calories) and intensity (measured in a unit called MET, metabolic equivalent task) during sexual activity and the endurance exercise was measured using a portable mini SenseWear armband.
The portable armband uses a 3-axis accelerometer (a device used to measure physical movement), a heat flux sensor, a galvanic skin response sensor, a skin temperature sensor, and a near-body ambient temperature sensor to capture data used to estimate energy expenditure.
Perceived energy expenditure, perception of effort, fatigue and pleasure were also assessed after sexual activity via a seven-point questionnaire.
Sexual activity was defined as the onset of foreplay, intercourse and at least one orgasm by either the man or woman and ended at the couple’s discretion. During a one month period, couples were instructed to perform one sexual activity per week in their homes so all couples had performed a total of four sexual activities. The couples were instructed to perform their usual sexual activities and not to use any drugs, alcohol or medication for erectile dysfunction (such as Viagra) before the sexual activity.
The main analysis compared the duration and intensity of the average sex session to the endurance exercise.

What were the basic results?

The average length of a sexual activity was 24.7 minutes (range 10 to 57 minutes). Average energy expenditure during sexual activity was 101 calories (4.2 calories per minute) in men, higher than that seen in women at 69.1 calories (3.1 calories per minute).
Energy expenditure through sexual activity was significantly less than the energy expended during the 30 minutes of exercise – which was 276 calories (9.2 calories per minute) for men and 213 calories  (7.1 calories per minute) for women.
Average sexual activity intensity was 6.0 METs in men and 5.6 METs in women, which represents a moderate intensity of exertion. This was again less than the intensity of the endurance exercise in men 8.5 METs and women 8.4 METs.
It was estimated that sexual activity represented around 71% of the intensity of the 30-minute endurance exercise, and 38% of the energy expenditure.
The highest range value achieved by men for absolute energy expenditure during sexual activity (306 calories) can potentially be higher than that of the mean absolute energy expenditure of the 30-minute exercise session (276 calories), whereas this was not observed in women.
Perceived energy expenditure during sexual activity was similar in men (100 calories) and in women (76.2 calories) when compared to measured energy expenditure, indicating they were good judges of their level of energy expenditure.
Only 5% of all participants reported that sexual activity was more strenuous when compared to the 30-minute treadmill exercise.

How did the researchers interpret the results?

The interpretation from the researchers was that “energy expenditure during sexual activity appears to be approximately 85 calories or 3.6 calories per minute and seems to be performed at a moderate intensity in young healthy men and women. These results suggest that sexual activity may potentially be considered, at times, as a significant exercise.”
In their discussion of the intensity of the exercise the researchers’ reported the level of intensity that is exerted from sexual activity “could be” higher than walking at 4.8 km/hour but lower to that of jogging at 8 km/hour. And that the level of intensity of sexual activity in the study “may give health professionals a better understanding on the potential risk for myocardial infarction in cardiac patients since this topic appears to be a preoccupation in the field of medicine.”


This study found the energy expenditure and intensity of sexual activity in 21 healthy young heterosexual couples was significantly less (approximately 38% of the total) than that expended during a 30-minute treadmill exercise at moderate intensity.
Some men exerted more energy during sex than the average expended on the treadmill, but this was the exception among men and was not seen in any women.
The practical implications of the research aren’t too clear. Arguably, the results are of more interest on a sociological level; we may live in a more open society compared to the past but the"nuts and bolts" of sex, such as "how often" or "how long?", remain very much a taboo subject for many people.
However, the authors’ hint that health professionals might find it useful to know that sexual activity may not be contributing to the recommended weekly physical activity tally.
A significant limitation of the study was it’s stringent inclusion and exclusion criteria. This meant the study group was very homogenous (comprising of similar traits) and not very representative of a diverse general population. The results are mostly applicable to young (average age 22.6 years), healthy, heterosexual, sexually active couples in stable relationships.
The researchers’ placed the energy expenditure of sexual activity in their study somewhere between a walk and a jog. This was based on a comparison with results from other studies presented in their discussion; it was not tested directly so it is unclear how accurate this estimate is.
It was also not clear how accurate the SenseWear armband was at measuring energy expenditure and intensity so the precise calorie estimates of the different physical activities may contain some error.
The researchers noted that the sexual intensity of sexual activity in their group (six METs in men) was much higher than those found in previous studies reporting three to four METS. This may highlight that sexual activity intensity and energy expenditure varies a lot among different people, or that the couples were more active than usual during sex because they knew they were being monitored.
The bottom line from this research was that sex did not appear to be on the same level as 30 minutes of moderate exercise on a treadmill, the recommended minimum level of activity to be achieved five times per week. 
If you want more frank advice about sex and ways you could improve your relationship with your partner, read talking about sex.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on twitter.

Links to the headlines

Links to the science

Frapper J, Toubin I, Levy J J. Energy Expenditure during Sexual Activity in Young Healthy Couples. PLOS One. Published online October 29 2013

Wednesday, 9 October 2013

Walking ‘could save 37,000 lives a year’ report claims - Health News - NHS Choices

Walking ‘could save 37,000 lives a year’ report claims - Health News - NHS Choices

reposted from:
crabsallover highlightskey pointscomments / links.

Strength and Flex - Health Guidelines

reposted from:
crabsallover highlightskey pointscomments / links.

Fancy a personal trainer but can't afford one? Download our Strength and Flex podcasts and get your fitness coach for free.

Podcast features

  • Free to download
  • Virtual personal trainer
  • Equipment-free
  • Easy to follow
  • Get fit in five weeks
  • Full body workout
  • Video clips
  • Use anywhere, anytime
  • Can be used with Couch to 5K programme
Let our virtual trainer coach you through a series of equipment-free exercises designed to improve your strength and flexibility.
The workout instructions and pace are easy to follow to ensure you perform each exercise correctly and in time.
Strength and Flex consists of five 35- to 45-minute podcasts, which are available as a mobile download for MP3 players, mobile phones, iPod and iPhones.
You can easily combine these workouts with our popular Couch to 5K running programme, by following the plans on alternate days of the week.
Starting with Strength and Flex podcast 1, your goal is to work your way up to podcast 5 in five weeks. To achieve this, you need to do each podcast at least three times in a week.
By podcast 5, you’ll be doing back, arm and leg stretches along with press-ups and squats with ease. You'll be feeling stronger, more flexible and full of energy to go about your daily life.
You can do these full body workouts anywhere and any time you choose. They can be done indoors or out in the park or garden, on your own or with a friend.

Getting started

  1. Download podcasts to your PC or Mac.
  2. Transfer files to an MP3 player.
  3. Press play and go!
All you need is enough space to walk about freely, a fixed bench, a wall and either some shoulder-height railings or a shoulder-height horizontal bar.
There are Strength and Flex video clips available of all the exercises in this series, so you can check you’re doing each move safely and effectively.
The Strength and flexibility plan will ease you into the habit of regular exercise, which will help you burn calories, lose weight and stay healthy.
Podcast 5 is designed to be used beyond the programme. It provides a regular 45-minute workout to de-stress and feel good.
Your coach for the five-week Strength and flexibility programme is Laura, whose friendly and encouraging voice is one of the reasons behind C25K’s success.
To exercise, wear something that's loose and comfortable in a breathable material, like cotton, and pick shoes that offer support and cushioning.
If you have any health concerns about beginning the Strength and flexibility programme, see your GP and discuss it with them before you start.

Strength and flexibility - Health tools - NHS Choices

source: Strength and flexibility - Health tools - NHS Choices

reposted from:
crabsallover highlightskey pointscomments / links.

Strength and flexibility podcasts
Fancy a free personal trainer? Download these free podcasts designed to guide you through a five week plan of exercises to improve your strength and flexibility. By week five, you'll be doing a 40 minute routine of press-ups, squats and stretches.

Physical activity guidelines for adults - Live Well - NHS Choices

source: Physical activity guidelines for adults - Live Well - NHS Choices

How much physical activity do adults aged 19-64 years old need to do to keep healthy?
To stay healthy or to improve health, adults need to do two types of physical activity each week: aerobic and muscle-strengthening activity.
How much physical activity you need to do each week depends on your age. Click on the links below for the recommendations for other age groups:

Physical activity for adults aged 19-64

To stay healthy, adults aged 19-64 should try to be active daily and should do:

At least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity such as cycling or fast walking every week, and  
             muscle-strengthening activities on 2 or more days a
             week that work all major muscle groups (legs,
             hips, back, abdomen, chest, shoulders and arms). 

75 minutes (1 hour and 15 minutes) of vigorous-intensity aerobic activity such as running or a game of singles tennis every week, and
             muscle-strengthening activities on 2 or more days a
             week that work all major muscle groups (legs,
             hips, back, abdomen, chest, shoulders and arms). 

An equivalent mix of moderate- and vigorous-intensity aerobic activity every week (for example 2 30-minute runs plus 30 minutes of fast walking), and
muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders and arms).   

What counts as moderate-intensity aerobic activity?Examples of activities that require moderate effort for most people include:
  • walking fast
  • water aerobics
  • riding a bike on level ground or with few hills
  • doubles tennis
  • pushing a lawn mower
  • hiking
  • skateboarding
  • rollerblading
  • volleyball
  • basketball 

5 x 30 minutes

One way to do your recommended 150 minutes of weekly physical activity is to do 30 minutes on 5 days a week.
Moderate-intensity activity will raise your heart rate and make you breathe faster and feel warmer. One way to tell if you're working at a moderate intensity is if you can still talk, but you can't sing the words to a song. 
What counts as vigorous-intensity aerobic activity?Examples of activities that require vigorous effort for most people include:
Vigorous-intensity aerobic activity means you're breathing hard and fast, and your heart rate has gone up quite a bit. If you're working at this level, you won't be able to say more than a few words without pausing for a breath.
In general, 75 minutes of vigorous-intensity activity can give similar health benefits to 150 minutes of moderate-intensity activity.
For a moderate to vigorous intensity workout, try Couch to 5K, a nine-week running plan for beginners.
What counts as muscle-strengthening activity? Muscle-strengthening exercises are counted in repetitions and sets. A repetition is 1 complete movement of an activity, like lifting a weight or doing a sit-up. A set is a group of repetitions.
For each activity, try to do 8 to 12 repetitions in each set. Try to do at least 1 set of each muscle-strengthening activity. You'll get even more benefits if you do 2 or 3 sets.

Healthy weight

  • Adults who are overweight can improve their health by meeting the activity guidelines, even if they don’t lose weight.
  • To lose weight, you are likely to need to do more than 150 minutes a week and make changes to your diet.
  • Start by gradually building up towards 150 minutes of moderate-intensity aerobic activity a week.
To get health benefits from muscle-strengthening activities, you should do them to the point where you struggle to complete another repetition.
There are many ways you can strengthen your muscles, whether it's at home or in the gym. Examples of muscle-strengthening activities for most people include:
  • lifting weights
  • working with resistance bands
  • doing exercises that use your body weight for resistance, such as push-ups and sit-ups
  • heavy gardening, such as digging and shovelling
  • yoga
Try Strength and Flex, a five-week exercise plan for beginners to improve your strength and flexibility.
You can do activities that strengthen your muscles on the same day or on different days as your aerobic activity, whatever's best for you.
However, muscle-strengthening activities don't count towards your aerobic activity total, so you'll need to do them in addition to your aerobic activity.
Some vigorous-intensity aerobic activities may provide 75 minutes of aerobic activity and sufficient muscle-strengthening activity. Examples include circuit training and sports such as football or rugby.
Page last reviewed: 11/07/2013
Next review due: 11/07/2015