Displaying 1-10 letters out of 279 published
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update searches have been implemented, it will be necessary for me to pay for an article that potentially only contains outdated, previously published material.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:
It is time to bust the myth of a catchy title.
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. http://www.aomrc.org.uk
Conflict of Interest:
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.
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
Conflict of Interest:
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, Dr Graham Baker, Dr Chloe McAdam, Dr Karen Milton, Dr Justin Richards, Prof Marie Murphy, Prof Charlie Foster[1,2], Prof Nanette Mutrie
On behalf of The Physical Activity for Health Research Centre, Institute of Sport, Physical Education and Health Sciences, University of Edinburgh; The British Heart Foundation Centre on Population Approaches for Non-Communicable Disease Prevention, Nuffield Department of Population Health, University of Oxford; School of Public Health, University of Sydney
- 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.
- 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.
- 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: http://www.sciencemediacentre.org/expert-reaction-to-editorial-on-sugar-carbohydrates-exercise-and-obesity/
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.
- 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 "
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:
- 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:
- 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?
- 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.
- 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 "
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" http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1898525/ 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.
- 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 "
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.
- 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.
- 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.
- 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.
Why is reference 3 given as an html link rather than in accepted journal format?
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.
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:
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:
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:
Re:Dichotomy in translation raises the need for careful definition in use
I would like to thank Dr Baxter for her kind words regarding the importance of my manuscript in highlighting the ambiguity in the use of the term intensity in the exercise sciences. I also agree fully that more careful definition might help to clarify the issue of its use. However, I think that better clarification of the definition of the term only further serves to highlight the issues associated with its use.
In correspondence with another academic in this area it was pointed out that my manuscript did not in fact discuss Intensity as defined under the Systeme International d'Unites which is power transferred per unit area (i.e. W.m-2). Further that in luminescence the term is defined differently again (candela per square metre i.e. cd.m-2). A number of manuscripts in previous years have discussed the misuse of Newtonian mechanical constructs in describing exercise and yet have opted for the continued use of intensity to describe the difficulty or 'hardness' of exercise (Knuttgen, 1978; Winter & Fowler 2009). I maintain that attempting to describe exercise in such a way is perhaps a wasted effort.
If, for example, we use 'Intensity' as defined under the Systeme International d'Unites as power transferred per unit area, and it is expressed as the unit watts per square metre (i.e. W*m-2), then technically any use of the term outside of this strict definition would constitute a misapplication, assuming it is taken to be the accepted definition in that context. This would also apply to the suggestions made by other authors (Knuttgen, 1978; Winter & Fowler 2009) more recently to use the term to describe how 'hard' exercise is but to differ the unit dependent on the context. Unless power per unit area is being measured or discussed would it perhaps not be better to avoid the term altogether in exercise science? If so then the word 'Intensity' could be avoided completely by just using the phrase 'power per unit area'. Alternatively, the problem appears to me that many within exercise science are probably more likely to consider the OED definition of 'Intensity' and as noted in my article the term becomes redundant once the construct being measured (and preferably the unit of measurement) is made clear. Further, the suggestion to avoid the word 'Intensity' entirely (unless referring to power per unit area) in order to avoid confusion is exemplified by the confusion that could occur from the situation (albeit unlikely) that the magnitude of 'power per unit area' is being considered. Both the SI and OED definition could be applied and result in curious statements such as "Intensity (OED Definition) OF Intensity (SI Definition)" (i.e. "Intensity OF W*m-2") which is very confusing (albeit rather amusing). Indeed, another proverbial can of worms could be opened by noting that 'hardness' is already considered a measurable variable in itself which refers to either scratch, indentation or mechanical resistance of minerals. Perhaps we should also leave this term alone as well except in colloquial verbiage and 'difficulty' or 'challenge' might be better suited. These could be defined along the lines of 'the overall demands of exercise relative to a person's immediate ability to meet those demands'. Neither term to my knowledge is currently under use with different application in other scientific disciplines such to cause confusion.
I agree fully with Dr Baxter's comments that variables such as 'load' and 'perception of effort' can indeed vary dependent upon the context. However, this does not seem to me to be a terminological issue as it is known that almost all dependent variables that can be measured may in fact differ dependent upon manipulation of other independent and confounding variables. For example, load measured by a 1RM may vary dependent upon number of factors such as those noted by Dr Baxter and thus the 1RM should be considered within the context of those factors. If one particular context permits a higher 1RM than all others it may be fair to say that this is indeed the individual's true maximum to the best of our knowledge. In this case using Dr Baxter's example that in such instances where 1RM may be reduced "...the (reported) intensity of the session would be higher despite lower loading...", instead it could be said that the loading relative to the true maximum was lower, however, relative loading under the circumstances was still maximal (a 1RM under the current conditions) despite a lower absolute loading. Similarly, perception of effort may differ dependent upon a number of factors despite the same exercise conditions being performed and indeed that many person's ability to rate their perception of effort on a continuum is poor. Indeed a good example of this, and which suggests even advanced trainees are not so good at predicting how close they are to their maximum effort, is seen where such trainees are asked to predict the number of repetitions they could perform to momentary muscular failure and initially under predict (Hackett et al., 2012). Perception of effort is also often confused with perceptions of discomfort or other physical sensations, as noted in my manuscript, which further confound this and suggests that the two should be differentiated in measurement and in reference.
In any case, it would appear that Dr Baxter along with most others persistence that 'intensity' should be used, albeit in combination with the unit of measurement being considered or "...defined in terms of reliable measures with which to underpin the definition in the respective study..." appears a redundant suggestion and a potentially confusing one. If the term intensity to describe the 'hardness' (difficulty/challenge?) of an exercise can be defined differently in different contexts dependent upon the variable being examined it potentially opens up many to again misinterpret its meaning. Why not instead just refer to the variable being considered (e.g. load, effort, heart rate, force/torque etc.) whilst considering the context under which it is being measured/examined?
1. Kunttgen HG. Force, work, power and exercise. Med Sci Sport 1978;10(3):227-228
2. Winter EM, Fowler N. Exercise defined and quantified according to the Systeme International d'Unites. J Sports Sci 2009; 27(5):447-460
3. Hackett DA, Johnson NA, Halaki M, Chow CM. A novel scale to assess resistance-exercise effort. J Sports Sci 2012;30:1405-1413
Conflict of Interest:
Response to "Is tendinopathy research at a crossroads?"
I fully agree with comments made by Masci regarding treatment for tendinopathy. I also practice at the coalface, treating tendon pain from elite to recreational athletes. The reality I face when prescribing exercise protocols is both a lack of evidence base as to the optimum program, and the harsh reality that most non-elite athletes will not strictly comply with complex home exercise programs, particularly where there is no rapid improvement in symptoms- people have busy and complex lives and it is not possible to simplify a complex life into a single tendon. I frequently opt for platelet rich plasma injections, as do many of my sports medicine colleagues. Anecdotally these work well, which, despite failing the evidence base test, passes the word of mouth test, and word of mouth is the source of many of my referrals. This is perhaps the major difference between research and the real world. If we adhere strictly to the evidence base, we should stop treating tendons altogether, and leave our patients in pain, as even the most widely used treatment programs have questionable evidence behind them. My approach is largely common sense based. Patients who are prepared to reduce loading on a painful tendon and work on a graded and comprehensive exercise program are offered that. Those who state outright that they will not do an exercise program, but wish to try PRP injections (because their friend/ relative/ sports colleague had great benefit) are not turned away, but given the treatment. I perform injections under ultrasound control, and treat gluteal and rotator cuff tendons as well as Achilles, patellar, and elbow tendons. Anecdotally most get better, and although this is not science, I am happy to inhabit the large grey area of tendinopathy treatment. I am also happy to follow the research, and change my approach as are knowledge evolves.
Conflict of Interest:
Dichotomy in translation raises the need for careful definition in use
Clarification on the definition of use of the term 'intensity' as raised by Steele certainly serves to highlight the continuing variation - and confusion - around use of this term. Due to the ambiguity as to whether intensity is a measured load or is synonymous with perceived level of exertion, Steele recommended abandonment of intensity as a descriptive word.
However it is my belief that the very dichotomy raised by Steele emphasises the need to quantify and define the term through the development and adoption of reliable and objective outcome measures, and ones that capture the dichotomy: i.e. the psychological (perceived level of exertion) and physiological (load) components of intensity.
Translation and definition of terms are fundamentally important in the communication of science: in fact the imperative of research papers reporting the details of the research methods employed depends in turn on the definition and language used to communicate the methods.
While I acknowledge that there are inherent problems in translation of the term intensity, I further believe there are issues surrounding the choice of definition being either 'load', or 'perception of exertion'.
For example, an individual's maximum 'load', or 1RM, is not constant: rather, it represents a hypothetical 'best'. It fails to recognise differing circumstances, including human factors, and instead assumes a mechanistic uniformity in ability for 1 RM. However, there are a number of factors which may affect the ability of a individual to achieve a 1RM, including stressors; injury or muscle tightness; pre-fatigue from other lifts; DOMS (delayed onset muscle soreness); or even calorific deficit or inadequate nutrition. In such instances the measured load of 1RM would be altered (albeit transiently), but the (reported) intensity of the session would be higher despite lower loading.
'Load' also does not capture other factors which affect the 'load' such as 'time'; if the lift is slowed down then there is more effort exerted without altering the load. Other ways of increasing the intensity of a lift without altering the load include reduced rest periods, more repetitions and 'concentration' sets whereby the person is restricted to main area of the workload (such as in squats the bottom half of range of movement).
Similarly there are challenges in advocating intensity as being synonymous with perceived level of exertion, which requires the objective ability of the participant to distinguish with accuracy the effort required in a given exercise session. This presents two problems: often the complete novice participant has low experience in determining what their effort is on a continuum, when compared to (say) that of the experienced lifter/athlete. Further to this, there is the issue that, both the novice and advanced lifter are inclined to responder bias in such circumstances. Although for the advanced lifter their experience while provide a more accurate quantification of perceived level of exertion (perhaps due to more instances for comparison), in both cases the accuracy is contingent on the responder (and their associated prior agendas/preconceptions).
It is my recommendation that intensity is not a term that becomes neglected or ceases to be used. The term must instead be defined in terms of reliable measures with which to underpin the definition in the respective study. These outcome measures should reflect the dual nature, and therefore, ambiguity in translation: they should include both physiological and psychological concepts, and measures. This would include and capture the level of exertion used while providing a more scientific foundation for replication.
Conflict of Interest:
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