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Displaying 1-10 letters out of 282 published

  1. Re:12 Reasons why the "Physical Activity Myth" paper should not have been published; Request for retraction or modification based on open external peer-review

    Kelly et al make a number of useful comments about the unfortunate editirial by Malhotra et al. However they too obscure the main point. They use a 2008 NIH document as the key reference to refute the editorialists' claim that exercise does not lead to weight loss.

    What the NIH document actually says -

    The magnitude of weight loss due to physical activity is additive to caloric restriction, but physical activity is generally insufficient by itself to bring about clinically significant weight loss.

    The accompanying figure very clearly demonstrates the degree to which exercise alone does not result weight loss, and cannot be promoted as a public health strategy to curb obesity.

    This quesiton is in fact the key issue at stake here, whatever one might think of the other dubious claims ay Malhotra et al.. Data accumulated since 2008 add further support to that conclusion. Only a lower intake of calories is effective as a means of weight reduction.

    As a co-author of a reference used in the ediorial, which argues that exercise alone is ineffective, I obviously have some stake in this debate and would like to see more tranparency on this issue. If there is a disagreement among observers we should at least be willing use the data sources correctly. Kelly et al are wrong to claim that -

    "All study designs provide clear evidence of a dose-response relation between physical activity and weight loss."

    In the spirit of rigor and honesty I think they should revise their criticism # 3. Even more importantly, they should provide evidence that exericse alone prevents or reduces obesity or they should acknowledge - as the NIH document does - that exercise alone is ineffective.

    Conflict of Interest:

    NIH funding on energy balance.

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  2. If you can click through to this Google+ Community I hope it will help...

    It seems very clear that there are two different ways of interpreting the tile of this editorial. BJSM is grateful for the terrific engagement in this important debate - we revel in debate.

    But it's not helpful to have two soliloquys going on so I respectfully suggest there are two basic interpretations of the title.

    Please click through to this Google Community to see the two interpretations and what may have been a better title (my fault on the title bit!)...

    You'll find more in the 'print' version of BJSM (ie. online in issue format) from July 17 - the issue of BJSM that puts a spotlight on South Africa and SASMA (South African Sports Medicine Association).

    Conflict of Interest:


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  3. Review

    This article speaks to the growing need to ensure all work groups including managers take the time to move around more frequently. It is also interesting to note that while this is based on short term studies it will have large long term gains. I will be very interested to see where this research goes in the future. I personally will be looking at ways to partake of this valuable insight in to the need to move away from my desk.

    Conflict of Interest:

    None declared

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  4. since you asked for my opinion

    Since the web site clearly asked for my opinion, I felt I wanted to share how disappointed I am with this article.

    This article looks like it is simply a copy of a systematic review / metaanalysis published a full 13 months earlier, in september 2013, meaning that the search was current in March 2012.

    The review was criticized at the time of its original publication for being overly optimistic (see the comments on your own web site). That the data is several years too old, will not help its reliability.

    If the review was updated, it could have some additional value over the original article. However, as it is impossible to tell from the abstract if any update searches have been implemented, it will be necessary for me to pay for an article that potentially only contains outdated, previously published material.

    Conflict of Interest:

    None declared

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  5. It is time to bust the myth of a catchy title.

    Dear Editor,

    It was disappointing to read the recent Editorial by Malhotra et al (1). Whilst the sentiment of the article was perhaps well placed, the desire for a headline grabbing title and catchphrase seems to have taken precedence over clear and honest content. A better title would have been "Three individuals are disgruntled with the marketing campaigns of soft drinks companies", but of course this would not have picked up much media attention. Furthermore, it seems odd that the opening paragraph suggests that the Academy of Medical Royal Colleges report placed undue emphasis on the benefit of exercise (2), given that Malhotra was also a co-author of this publication.

    The consequence of trying to create a media buzz is that the intended message is diluted and becomes confusing to the public. The authors make some eminently sensible suggestions around the importance of a healthy diet and the negative effects of high sugar consumption, along with insightful comments on celebrity endorsements and marketing of junk foods. However, the key message that actually comes across, and has subsequently been dispersed through various news channels, is that if you are overweight, there's no point in exercising. This of course is misleading, untrue and completely distracts from, for example, the positive benefits that regular physical activity can have on the cardiovascular, metabolic and psychological systems along with chronic disease prevention for individuals regardless of body mass index.

    Losing weight and being thin are not surrogates of true health, but rather a misrepresentation of the healthy body portrayed and perpetuated by the media. Unfortunately, it seems the authors have been caught up in this celebrity thinking - the very thing that they apparently wanted to argue against.

    Contrary to what the authors suggest, I doubt that most people buy into the concept that obesity can be reversed just by getting overweight individuals to exercise. If this were the case, there would be no "try this new diet to look like a model" books appearing on the shelves after Christmas. Similarly, no-one expects to increase their muscle strength simply by eating a chicken salad. A healthy lifestyle is not exclusively about either eating well or exercising, but rather requires attention to both areas.

    Rather than trying to polarize for the sake of a catchy title, Malhotra and authors should get the weighing scales out and learn how to write a balanced review of the scientific literature.

    References: (1) It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet. Malhotra A, Noakes T, Phinney S. Br J Sports Med doi:10.1136/bjsports-2015-094911 (2) Exercise - the miracle cure. Report from the Academy of Medical Royal Colleges. Feb 2015.

    Conflict of Interest:

    None declared

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  6. Response to paper: It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet

    Dear A Malhotra, T Noakes, and S Phinney,

    Please find below my thoughts on your paper.

    Having read your submission thoroughly I have great praise for its contents. The assessment of the food industry and advertisement is a thorough one. The food industry markets and targets in a morally reprehensible way that has no consideration for people's health at all and is a profit driven machine that needs addressing.

    However, in light off the media attention that this article has gained I have several criticisms of your article. It is my belief (and please correct me if I am wrong) that in order to gain attention to the marketing of sugary foods and industry conduct you have added a misleading title to your article

    Firstly you have provided no evidence to support your theory that exercise does not contribute to weight loss. Simplistically put exercise (increased body function) when combined with a consistent diet will induce weight loss. That is factual. Not only is it factual but it is common knowledge also.

    I understand the cause and the reasoning behind the approach however. Often when tackling this level of industrial misbehavior, media backing is essential. Otherwise the research can easily be overlooked and discredited without public oversight. The issue I see arising is that unfortunately you may well have discredited yourselves without need for others to challenge.

    The current media situation is that rather than good research being reported on, research is reported on that gains attention. I believe that your paper has some very valuable points. I think those points will now be lost due to the incorrect focus in your paper's title.

    I hope that you make headway with your cause. You may now wish to look into the following paper as to how best to combat the effects that you have inadvertently caused. misinformation.html

    Sometimes trying to get the correct information out there is like walking through treacle. It is hard going and you make little progress. However the easy solution is never the right one. Few people will read the full article. Less still will read far enough to understand why you have done, what you have done.

    I hope for future endeavors this response helps.

    Best of luck for the future

    Robert Mason

    Conflict of Interest:

    None declared

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  7. 12 Reasons why the "Physical Activity Myth" paper should not have been published; Request for retraction or modification based on open external peer-review

    To The Editor,

    We read your recent editorial "It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet" (Br J Sports Med doi:10.1136/bjsports-2015-094911) with interest. While we agree that discussion about the prevention and treatment of obesity is vital for scientific progress, we feel this article in its current state did not make a positive contribution to ongoing scientific debate.

    We understand that the editorial was written to be provocative, but we are concerned about the potential damage that can be done by publishing misleading and extreme opinions on issues of important public concern. We believe that that there are serious flaws in the writing, interpretation, understanding and quality of this article that should not go unchecked.

    The process of peer-review normally helps authors avoid presenting flawed arguments and editors to avoid publishing misleading articles. We wish to offer an open and retrospective external review of this editorial as if we had been asked to undertake this process. Our focus is not on disagreeing with the article, but rather, on maintaining the highest standard of scientific argument and debate.

    We ask you to consider this for publication as an open Letter to the Editor or that it is used in the BJSM educational section on critique. We invite discussion and criticism of our review, and will gladly amend any sections that can be shown to be incorrect. In line with the peer-review process, we invite the authors to rebut our critique, or modify or retract their arguments as appropriate.


    Dr Paul Kelly[1], Dr Graham Baker[1], Dr Chloe McAdam[1], Dr Karen Milton[2], Dr Justin Richards[3], Prof Marie Murphy[1], Prof Charlie Foster[1,2], Prof Nanette Mutrie[1]

    [1]On behalf of The Physical Activity for Health Research Centre, Institute of Sport, Physical Education and Health Sciences, University of Edinburgh; [2]The British Heart Foundation Centre on Population Approaches for Non-Communicable Disease Prevention, Nuffield Department of Population Health, University of Oxford; [3]School of Public Health, University of Sydney

    Major Revisions

    1. 1. Title: In the title the authors refer to the "myth of physical inactivity and obesity"

    What myth are the authors referring to? This should be outlined in the introductory paragraphs. We do not see any myths presented for discussion in the article - indeed much of the content has nothing to do with this title. If the authors are referring to an association between Coca Cola and sport (see point 8) the title and text should clearly reflect this. Until this is changed, or supported by content, the article should not be published.

    1. 2. Title: "you cannot outrun a bad diet"

    Regardless of the validity of this statement, running is not the only alternative to physical inactivity - this wording is misleading and should be changed or removed. Running makes a very small contribution to overall physical activity levels among the general population. We refer the authors to this article by Belanger, Townsend and Foster (2011), Prev Med. 52(3-4):247-9 which demonstrates how physical activity profiles are dominated by walking, occupation and domestic activity:

    As such the authors need to decide if the article is focussing on running or all physical (in)activity, and amend the title and/or content accordingly.

    1. 3. Paragraph 1 "However, physical activity does not promote weight loss"

    This statement is not supported by any citation or reference and should be removed because it is both speculative, and not reflective of current evidence. We advise the authors to consult the Physical Activity Guidelines Report (page G4-1 to G4-37) which refers to peer-reviewed evidence (prospective cohorts and randomized trails) and concludes "All study designs provide clear evidence of a dose-response relation between physical activity and weight loss."

    The authors should also see the critique by Prof Susan Jebb in which she highlights evidence that combining PA and diet change is the best method of weight loss and maintenance of weight loss:

    It would be acceptable on this point to say that the evidence is equivocal (especially for the magnitude of effect), and there is debate amongst experts. However, by failing to do this the authors are miss-representing the evidence. The quoted statement should therefore be modified or removed.

    1. 4. Paragraph 2 "In the past 30 years, as obesity has rocketed, there has been little change in physical activity levels in the Western population [2]"

    The cited reference does not support this claim, or present any evidence for the statement. The cited reference says a "labour-saving culture was fully in place by the 1960s-70s" but presents no evidence and cites a book without page or chapter numbers. Regardless of validity or errors on time-frames or contradicting the authors' assertions, this is a sweeping unsupported statement and should be removed.

    We refer the authors to (amongst others) Ng and Popkin (2012), Obesity Reviews, 13: 659-680, which provides evidence of decreasing MET expenditure in the US and the UK in the time-frame the authors refer (i.e. last 30 years) and directly contradicts the unevidenced statement of the authors:


    1. 5. Paragraph 2 "This places the blame for our expanding waistlines directly on the type and amount of calories consumed."

    The evidence presented does not allow causation to be ascribed. The authors later cite Bradford-Hill and therefore presumably understand the criteria which should be satisfied for causation to be claimed. The authors also contradict their own argument here, as they infer that if physical activity was changing (point 4) then it would also have an effect on obesity. This statement should therefore be removed. We point the authors towards the Foresight Report figure which elegantly depicts over 70 potentially interconnected causal pathways that could explain obesity:

    1. 6. Paragraph 3 "members of the public are drowned by an unhelpful message about maintaining a 'healthy weight' through calorie counting, and many still wrongly believe that obesity is entirely due to lack of exercise."

    The authors should clarify if this is an article about messages on calorie counting or messages on physical inactivity? This text should be removed as it is irrelevant.

    "and many still wrongly believe that obesity is entirely due to lack of exercise."

    This should be supported with evidence, identified as pure speculation, or removed. Can the authors cite any evidence that people believe that obesity is entirely due to lack of exercise?

    1. 7. Paragraph 4: "Coca Cola, who spent $3.3 billion on advertising in 2013, pushes a message that 'all calories count'; they associate their products with sport, suggesting it is ok to consume their drinks as long as you exercise."

    If this is the "myth of physical inactivity and obesity" the authors are referring to in the title the authors should re-title their article "It is not OK to drink soft drinks even if you exercise". The current title does not reflect this assertion.

    1. 8. Paragraph 5: "A large econometric analysis of worldwide sugar availability, revealed that for every excess 150 calories of sugar (say, one can of cola), there was an 11-fold increase in the prevalence of type 2 diabetes, in comparison to an identical 150 calories obtained from fat or protein. And this was independent of the person's weight and physical activity level; this study fulfils the Bradford Hill Criteria for causation [6]"

    This evidence (reference 6) relates to type 2 diabetes (which the authors already acknowledged was ameliorated by exercise). It is not evidence that exercise is ineffective for obesity, it does not address what appears to be the original objective of the article, and it should be removed.

    As a further comment can the authors explain how this evidence fulfils Bradford-Hill criteria number 8: Experiment? To quote Bradford-Hill: "Here the strongest support for the causation hypothesis may be revealed" The presented evidence (reference 6) is repeat-cross sectional data, and presumably does not fulfil the experimental criteria.

    It is revealing that in reference 6 the original authors (Basu et al) say the following:

    "...any of the findings we observe here are meant to be exploratory in nature, helping us to detect broad population patterns that deserve further testing through prospective longitudinal cohort studies in international settings, which are only now coming underway"

    It is clear the original authors felt this was an early and ongoing line of enquiry, rather than the conclusive evidence this editorial leads the reader to believe. This is further cause for removing or amending this text.

    1. 9. Paragraph 5: "A recently published critical review in nutrition concluded that dietary carbohydrate restriction is the single most effective intervention for reducing all the features of the metabolic syndrome and should be the first approach in diabetes management, with benefits occurring even without weight loss [7]"

    The authors have cited this critical review over any systematic review when the latter are available and acknowledged as a higher quality of evidence. Such 'cherry picking' of the available evidence is unscientific and unhelpful for the reader. Further, the authors have chosen a paper that suggests that carbohydrate restriction should be the first approach for metabolic syndrome, even without weight-loss, when the objective of the current article is focussed on obesity. It is therefore irrelevant. For these reasons this text should be removed.

    1. 10. The section titled "And what about carbohydrate loading for exercise"

    This section does not address any points that physical inactivity is ineffective for obesity and should be removed. It is unclear why this information has been presented it appears to be developing a new theme that is not related to the focus on physical activity for health but would be more appropriately located in an article about physical performance.

    1. 11. Paragraph 7: "The public health messaging around diet and exercise, and their relationship to the epidemics of type 2 diabetes and obesity, has been corrupted by vested interests."

    Given this criticism the author should explain how their editorial has helped the public health effort. ?We would suggest that this editorial, which has ignored high quality evidence for the effectiveness of physical activity (with and without modified diet) for weight control, is further contributing to miss-leading and potentially dangerous public health messages.

    1. 12. Final paragraph: "Let us bust the myth of physical inactivity and obesity. You cannot outrun a bad diet"

    As indicated earlier this is an inappropriate, unsupported and invalid conclusion based on the evidence presented and should therefore be removed.

    Minor changes

    Why is reference 3 given as an html link rather than in accepted journal format?

    Overall decision

    Reject as scientifically unsound.

    Edinburgh, UK, 16th May 2015

    Conflict of Interest:

    We declare that we have an interest in physical activity research, public health and the maintenance of the highest academic standards. We receive funding from a number of national and international research councils, and companies that make devices for physical activity and sedentary behaviour research. We do not receive funding from the food industry.

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  8. Inertia makes you hate work-cause or effect?

    The most important ingredient for workplace satisfaction is meaningful engagement, which would liven our move and energy. Boredom and scarcity of challenge leads to inertia-mental and physical.

    Engagement enlivens flagging concentration,finds value and purpose in our desired vocation and offers sustained opportunities to sharpen focus on demanding tasks, which in turn boosts productivity and company profits.

    What tends to get lost in this economized assessment are improved health outcomes, self-rated health and job satisfaction for workers. This a win-win situation for managers and their employees. Loyalty and staff retention are enhanced and there is reduced absenteeism.

    Sick leave, widely viewed as an entitlement that is lost unless it is used up for even non-illness reasons, is intended to be a privilege that benefits the unwell worker's recovery but incurs a substantial level of associated abuse. Being happy and armed with purpose in the workplace encourages presenteeism. Better performing employees also make for happier managers, a self-pepetuating cycle of positivity.

    Conflict of Interest:

    None declared

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  9. LCHF LIfestyle

    I have been on the LCHF lifestyle for about 18 months and have experienced huge improvements to my health. I am no longer obese, my blood pressure has normalised, my lipid and glucose profiles have improved, sleep apnoea has ceased, no more heartburn and energy levels have improved.

    This has all been possible using the guidance contained in the books of the two authors and also gary taubes, robert lustig and nina teicholz.

    There is no doubt in my mind that I am addicted to sugar which I have now totally excluded from my diet after years of very heavy consumption

    Conflict of Interest:

    None declared

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  10. The need to think twice before making a press release

    I write as an academic health psychologist, whose main interest is changing behaviour toward healthier living. A BBC News article entitled "Exercise 'not key to obesity fight'" drew my attention to this editorial.

    On reading the full text, I discovered that the authors were mainly writing about the causes of obesity, rather than about change. No doubt the one controversial statement in the editorial (unsupported by citations) that "physical activity does not promote weght loss" will be challenged. In any case, the causes of a phenomenon and what changes it are not always the same; for example, anxiety can be conditioned by experiences but still relieved by anxiolytic drugs or by psychological techniques. Despite this, a number of interesting and important arguments were made that merit further attention. Many of the points will stimulate much-needed debate, such as the role of promoting unhealthy foods by food companies.

    However two factors concern me as a scientist. Firstly an editorial by its nature presents opinions - and it was not peer-reviewed. While the arguments are backed up by selected empirical findings, an editorial is still a work of opinion. We are not talking about findings of a rigorous new meta-analysis or systematic review, so the statements should be made with a corresponding level of tenuousness - especially in a press release. Secondly, it was always likely that the media would misinterpret this nuanced message on a topic extremely important to the health of millions, yet a press release was still made.

    Up to now, nearly everyone involved in the field of healthcare (in research and practice) has been doing as much as they can to encourage those who are overweight to exercise regularly. With headlines like this, the population now receives a mixed message. I do not know what the motivation for writing this editorial was, but it will no doubt undermine a great deal of work and have a negative impact on health.

    Before making a press release, researchers need to consider the potential consequences. Journalists are not scientists; they may misinterpret subtle messages or select only those which appeal to their readers or audience. Furthermore, readers of the news media are often intelligent but are also not scientists: if presented with a message from "experts", it has an impact on the beliefs that, along with other factors, determine how a person acts. It is well-established from research on the psychology of persuasion that credibility of source affects the credibility of the message.

    It is a risk that some obese people who have seen this story and currently struggle with physical activity will now give up - because they believe (from the news) that "experts" have given the message that exercise doesn't matter. Surely the authors could have foreseen that news media and the general population would misinterpret their message as being that exercise was not necessary? In addition, a look at the comments under the BBC News article show that many users see these conflicting recommendations from "experts" as undermining their trust in science.

    As seen in the scandal about the MMR vaccine and autism, while science is self-correcting, public opinion and behaviour can be slow to recover. MMR vaccination rates took a decade to return to baseline following widespread media coverage of what was later revealed to be flawed research. While the public benefits by being alerted to important findings, the rush to a press-release can have unforeseen consequences. As researchers working in the field of health, if our work enters the domain of journalism, we can lose control over the message.

    I encourage the authors, journal publishers and all other researchers to think carefully about whether to make a press release, what it contains, and what can happen when their message is distorted. Once the press release is made, the die is cast and a game of "Chinese whispers" can begin. If the message is misinterpreted, the researcher cannot close the stable door after the horse has bolted. And the researcher(s) - who are ultimately responsible for the ideas they promulgate - must shoulder some of the responsibility for the consequences.


    Dr. Francis Quinn

    Conflict of Interest:

    None declared

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