You don't need to be signed in to read BMJ Blogs, but you can register here to receive updates about other BMJ products and services via our site.


Feasibility and efficiency of an under-desk exercise device: a pilot study

24 Sep, 12 | by Karim Khan

By Drs  Vadim N. Dedov and Irina V. Dedova


Background/Aim – Sedentary behaviour is associated with a variety of chronic diseases and considered as a health hazard. Worksite interventions, which decrease sedentary time and increase physical activity during working hours, may improve health of sedentary workers.

Methods – In this study we tested a specially designed exercise device, which allowed linear feet movements at the horizontal plane and hence the under-desk use. The device had friction resistance mechanism, which was equipped with a temperature sensor for objective monitoring of exercise intensity, duration and amount of exercise. Four healthy volunteers were provided with continuous access to the device during their normal activities at the desk.

Results – It was shown that the amount of exercise achieved during 30-minute dedicated device usage at moderate intensity was 131.0 kC⁰, as measured by the heat production in the device. According to the current exercise guidelines, this amount of exercise could be considered as the recommended daily amount of physical activity. Exercise concurrent with the use of computer resulted in the device usage equal to 251.6 kC⁰. The concurrent exercise was of lower intensity than dedicated exercise, but longer duration of device usage, which was achieved in several bouts, resulted in accumulation of significant total amounts of exercise.

Conclusion This study suggested for the first time that under desk exercise could complement the use of computer and result in accumulation of amounts of exercise exceeding the recommended daily amounts of physical activity. Larger studies are warranted for evaluation of under desk exercise in various sedentary occupations.



Physical inactivity is considered as an important health hazard and reduction of sedentary behaviour could improve population health by preventing the development of chronic diseases.1 However, the levels of physical activity at work are continuously declining2 and full-time workers in sedentary occupations remains immobile for approximately 11 hours per day and don’t have enough leisure time for sufficient exercise.3 Unfortunately, modern megatrends in information and communication technology may negate the effects of planned physical activity interventions.4 Conversely, regular physical activity in the workplace would result in decrease of sedentary time and hence in improvement of employees’ health. A variety of worksite exercise programmes were tested to increase employees’ physical activity.5 However, it might be argued that short bouts of exercise (e.g. use of stairs) are not lengthy enough for substantial reduction of sedentary time, whereas dedicated exercise bouts require allocation of extra time during working hours.

Exercise devices facilitate regular physical activity and three major types of conventional fitness machines were tested in the workplace. The use of treadmill was shown to be compatible with the worksite activities of medical transcriptionists6 and it was calculated that replacement of sitting with walking-and-working computer time for 2-3 hours/day would result in a weight loss of 20-30 kg/year in obese workers.7 However, treadmill walking caused decrease in the measures of fine motor skills and math problem as compared with seated conditions.8 A miniature bike installed in the office was used for 23.4 minutes a day on 3 out of 5 working days.9 A miniature stepping device increased the energy expenditure over sitting condition and it was calculated that, if it used to replace sitting by 2 hours per day, weight loss of 20 kg/year could occur.10

The under desk exercise device would have the advantage of convenience and accessibility for prolonged use during working hours. In this study we tested feasibility and efficiency of specially designed under-desk exercise device.



A novel resistance exercise device MedExercise ST (MDXD Pty Ltd, Australia) was used in this study (Figure 1A). Changes of temperature in the resistance unit were measured with a temperature sensor connected to the industrial multimeter IP57 (Digitech, Australia). Data was collected using respective software Multimeter V1.0 from Digitech and then converted into Excel databases (Microsoft, U.S.A.) for analysis. The average exercise-induced rise in temperature was calculated after subtraction of ambient temperature values. The heat production during usage of the device was expressed in kCo (average + SD), which was the average exercise-induced rise of temperature multiplied by the duration of recording in seconds. Fingertip pulse-oximeter CMS-50E (Contec, China) and corresponding SpO2 Review software were used for the continuous measurement of heart rates during the exercise. Overall, four healthy volunteers, aged between 36 and 49 years, participated in this study. Respective informed concerns were obtained. Statistical analysis was performed using the Student’s t-test.



Figure 1A shows the user sitting in the stationary chair, such as a standard visitor chair. During the exercise user’s feet were moving in horizontal plane without rising of the knee that allowed leg movements under the desk. Repeated leg flexion-extension cycles resulted in physical efforts of the user and respective heat production in the resistance mechanism of the device due to friction. Figure 1B shows that the usage of device installed under the desk caused a fast rise of temperature to the plateau level, whereas stopping of exercise resulted in a drop of temperature to the pre-exercise values.

The current physical activity guidelines suggest that all healthy adults aged 18 to 65 years need moderate intensity aerobic physical activity for a minimum of 30 min on 5 days each week’.11 Therefore, 30-minute usage of under-desk exercise device in moderate intensity could be considered as the recommended daily amount of exercise. Accordingly, the device was used for 30 minutes (Fig. 1B, pattern filled area) with no other activities involved (dedicated exercise). At this intensity of device usage, a pulse rate of the participant was around 100 bpm (Fig. 1C), which indicated a moderate intensity of exercise in healthy adults.12

The amount of device usage and hence the amount of exercise were calculated as the average exercise-induced temperature rise multiplied by the duration of recording expressed in seconds (Fig. 1B, double sided arrow). Overall, dedicated under desk exercise for 30 minutes resulted in the average temperature rise of 43.4+6.6 C⁰ and the corresponding total amount of device usage of 131.0+15.7 kC⁰ (n=5) (Fig. 1E and 1G, respectively). According to the current exercise guidelines,11 this amount of exercise might be considered as the recommended daily amount of physical activity, which was achieved solely by using of under-desk exercise device.

For the next set of experiments, the under-desk exercise device was used, while working with desk computer (concurrent exercise). A typical recording of exercise intensities during the concurrent exercise is presented at Fig. 1D. In this example a total duration of recording was 232 minutes (double sided arrow), which included the actual using of the device at various intensities for 146 minutes (pattern filled areas), breaks and time away from the desk. In contrast to the uniform intensity of device usage in dedicated exercise (Fig. 1B), the concurrent exercise pattern demonstrated significant variability in exercise intensity (Fig. 1D). Overall, the recording time was 221.6+67.5 minutes (n=7), including 128.5+25.1 minutes of actual exercise, which constituted 58% of the total recording time (Fig.1F). The average intensity of concurrent exercise was 18.9+4.7 C⁰ and a total amount of device usage amounted to 251.6+55.5 kC⁰.

Therefore, the average intensity of concurrent exercise was 2.3 times lower than in dedicated exercise (Fig. 1E). However, the longer total duration of device usage (Fig. 1F), which was accumulated during several exercise bouts separated by breaks, resulted in 1.9-fold larger amount of exercise than in 30-minute dedicated exercise (Fig. 1G). It could be calculated that on average 68.7 minutes of concurrent usage of the device was required to equal the recommended daily amount of physical activity achieved by the 30-minute dedicated exercise using the same exercise device.



Significant evidence is presented for the benefits of worksite exercise in sustaining employee health, whereas the technical features of conventional fitness machines may limit their use in the workplace. For example, installation of  ‘walk-and-work’ desk, which is based on treadmill, requires a significant modification of the workplace.13 In contrast, MedExercise ST was designed for use under the desk and hence can be used seated with the standard desks and chairs with no modifications.

Using this device, we have demonstrated for the first time the feasibility of effective under desk exercise at sufficient intensity and duration to be considered as the recommended daily amount of physical activity.11 This pilot study also suggested that the under-desk exercise machine could be used concurrent with computer and hence in the workplace. Therefore, it might be an effective tool for reducing time spent sedentary while at work and for achieving the recommended daily amount of exercise. Since the lower average intensity of concurrent exercise, it required longer duration of device usage (e.g. 68.7 minutes) to equal the recommended 30-minute daily exercise of moderate intensity.11 Nonetheless, 68.7 minutes constitutes only ~10.4% of daily sedentary time of working population.3

Importantly, the concurrent exercise does not require significant modifications of the lifestyle in order to allocate dedicated time for exercise. It might result in better adherence to regular physical activity regime and provide better health outcomes when used in combination with other modes of physical activity. Limitations of our study include a small number of participants and types of sedentary activities that warrants further studies. Future research is also needed to evaluate effect of the under desk exercise on employee productivity, health and weight loss.


Competing interests

Dr Vadim Dedov has a stake in MDXD Pty Ltd, which designed and produced the equipment used in this study.


This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

Contributorship Statement

Both authors contributed equally in experimental design, data collection and analysis, and preparation of manuscript, which has been read and approved by them.


1.    Lee IM, Shiroma EJ, Lobelo F, et al. Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy. Lancet 2012;380:219-29.

2.    Castillo-Retamal M, Hinckson EA. Measuring physical activity and sedentary behaviour at work: a review. Work 2011;40:345-57.

3.    Tudor-Locke C, Leonardi C, Johnson WD, et al. Time spent in physical activity and sedentary behaviors on the working day: the American time use survey. J Occup Environ Med 2011;53:1382-7.

4.    Pratt M, Sarmiento OL, Montes F, et al. The implications of megatrends in information and communication technology and transportation for changes in global physical activity. Lancet 2012;380:282-93.

5.    Archer WR, Batan MC, Buchanan LR, et al. Promising practices for the prevention and control of obesity in the worksite. Am J Health Promot 2011;25:12-26.

6.    Thompson WG, Levine JA. Productivity of transcriptionists using a treadmill desk. Work 2011;40:473-7.

7.    Levine JA, Miller JM. The energy expenditure of using a “walk-and-work” desk for office workers with obesity. Br J Sports Med 2007;41:558-61.

8.    John D, Bassett D, Thompson D, et al. Effect of using a treadmill workstation on performance of simulated office work tasks. J Phys Act Health 2009;6:617-24.

9.    Carr LJ, Walaska KA, Marcus BH. Feasibility of a portable pedal exercise machine for reducing sedentary time in the workplace. Br. J. Sports. Med. 2012;46:430-5.

10.  McAlpine DA, Manohar CU, McCrady SK, et al. An office-place stepping device to promote workplace physical activity. Br J Sports Med 2007;41:903-7.

11.  Haskell WL, Lee IM, Pate RR, et al. Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Med. Sci. Sports. Exerc. 2007;39:1423-34.

12.  Norton K, Norton L, Sadgrove D. Position statement on physical activity and exercise intensity terminology. J Sci Med Sport 2010;13:496-502.

13.  Thompson WG, Foster RC, Eide DS, et al. Feasibility of a walking workstation to increase daily walking. Br. J. Sports Med. 2008;42:225-8.

Figure caption

Figure 1. (A) Position of the participant in stationary chair during exercise, using MedExercie ST device; (B) An example of exercise-induced temperature rise during 30-minute dedicated under desk exercise; (C) An example of the exercise-induced changes of participant’s pulse rate during 30-minute dedicated under desk exercise (bmp – beats per minute); (D) An example of exercise-induced temperature changes during under desk exercise concurrent with the use of computer; B-D: Pattern filled areas are periods of the actual using of the device. Double sided arrows show the duration of exercise intensity recordings. (E) Average intensity of device usage during the dedicated (DE) and concurrent (CE) under desk exercise, *P<0.01. (F) Average recording time of the dedicated (DR) and concurrent (CR) under desk exercise, and average duration of the actual device usage during concurrent exercise (CE); (G) A total amount of exercise achieved during dedicated (DE) and concurrent (CE) under desk exercise, *P<0.01.


Vadim N. Dedov, M.D., Ph.DFaculty of Medicine, University of New South Wales, NSW, Australia

Irina V. Dedova, M.D., Ph.DSchool of Medical Sciences, University of New South Wales, NSW, Australia


CT scans and X-rays increase risk of cancer – changing the goal posts in sports medicine

19 Sep, 12 | by Karim Khan

By John Orchard and Jessica Orchard

Two jaw-dropping papers from The Lancet 1 and BMJ 2 published in the past month should have a major effect on the practice of sports medicine.  They have clearly demonstrated that radiating scans in young people actually do lead to an increased risk of cancer later in life. Perhaps until 2012 this was a theoretical risk, but as of the publication of these landmark papers 1-3 we can be certain that the increased risk is not zero. There will be much more to come in this field over the next few years and it will dramatically change the landscape of radiology and all medical practice.

Pearce and colleagues’ study in The Lancet looked at the excess risk of leukaemia and brain tumours for children and young people exposed to CT scans. They found that children exposed to cumulative doses of 50mGy in CT scans may have triple the risk of leukaemia, and doses of 60mGy may have almost triple the risk of brain tumours1. Though this appears to be a massive increase in risk, the authors point out that these cancers are still relatively rare, causing an estimated one excess case of leukaemia and one excess brain tumour per 10,000 head CT scans. They are clearly cause for concern, as indicated by the fact that 12 other groups from 15 countries are studying the risk of scans on children3.

These Lancet findings are more striking when combined with the findings of Pijpe and colleagues’ GEN-RAD-RISK paper published last week in the BMJ2. This study showed that when women who carry a specific mutation associated with breast cancer (BRCA1/2), and who  were exposed to diagnostic radiation before the age of 30, had almost twice the risk of breast cancer (with a dose-response pattern). This study involved lower doses which we have previously considered fairly ‘safe’ (e.g. 4mGy from a single mammogram or shoulder x-ray). Therefore, BRCA1/2 carriers, with an already increased risk of a very common cancer, would be particularly at risk from exposure from radiating scans at a young age.

Why does this matter for sports and exercise medicine?

Sports and exercise medicine is a field in which most patients have many years of life expectancy remaining; it is also a field in which diagnostic imaging is very common. Imaging is often confined to the limbs but also involves the spine.  Importantly,  the GEN-RAD-RISK paper showed, for example, that shoulder X-rays in women with the BRCA1/2 mutation can increase the risk of breast cancer. This does not prove that a shoulder X-ray is unsafe for the entire female population, but because it is quite plausible, we need to reassess the use of radiating scans. The authors of this study have already recommended that women with the BRCA1/2 mutations should not get mammograms and it is hard to see how this recommendation will not soon be extended to all younger women, as mammograms are meant to be preventing deaths from cancer, not causing them.

Studies have not been published to look at, for example, the risk of  cancers in the abdominal cavity (e.g. bowel, ovarian) after lumbar spine CT scan, but again we have to presume from the existing knowledge that the increased cancer risk is not zero. In this case,  the unknown is the size of the increase in cancer risk (and not whether there actually is one). All tests (and treatments) in medicine need to consider benefits, risks and costs. On the benefit side, the test which gives the best information relevant to management needs to be identified. This can’t be done in isolation of the increased cancer risk of radiating scans, particularly in young or middle aged patients.

There will still be cases where a test that involves radiation is going to give preferred information to a non-radiating one – a classic example being in the knee of a 70 year old, where X-ray will tell what needs to be known in 95% of cases and MRI scan is generally an excessive use of imaging. However in scenarios where we used to recommend radiating tests (e.g. CT and bone scan to investigate for suspected pars stress fracture in an adolescent) we may need to quickly change to a recommendation of first line MRI scan to avoid increasing the risk of cancer. Health systems are going to need to change in scenarios where radiating tests are funded but non-radiating tests aren’t, because clearly it would raise ethical questions for a health system to be funding (offering a financial incentive) to have a test which can increase a patient’s risk of cancer when a non-risky test is available but unfunded.

Up to fifty years ago, some shoe stores used to perform X-rays on the spot to show whether a kid’s shoe was fitting well4 – this practice is now considered archaic.  Sensibly there is now an attitude in medicine that a pregnant woman should not receive an X-ray or CT scan if the information could be obtained in any other fashion. We are probably heading into an era where the same attitude needs to apply to all children and young people, for CT scan and even X-ray. Modalities such as MRI and ultrasound (and good old-fashioned clinical examination) will need to become more prominent in sports and exercise medicine, at the expense of radiating examinations. These studies highlighted in the blog will generate a demand for consensus meetings involving sports physicians, radiologists, radiation physicists, and epidemiologists among others to provide guidance for clinicians, professional bodies and patients. Depending on the recommendations made at consensus meetings, there should ideally also be a review of government/insurance funding arrangements to remove any financial incentives towards the inappropriate use of radiating scans.


John Orchard is an Australian sports physician who has worked with numerous professional team sports. His sometimes controversial views are personal and not necessarily representative of organisations he is affiliated with. You can read more at www.johnorchard.comand/or follow @DrJohnOrchard on Twitter

Jessica Orchard is an Australian lawyer with qualifications in economics and public health, currently employed at the NSW Cancer Council. Her views in blogs are also personal and not necessarily representative of her affiliated organisations.


  1. Pearce MS et al. Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study. Lancet. 2012 Aug 4;380(9840):499-505.
  2. Pijpe A at al. Exposure to diagnostic radiation and risk of breast cancer among carriers of BRCA1/2 mutations:  retrospective cohort study (GENE-RAD-RISK).BMJ. 2012 Sep 6;345:e5660.
  3. Einstein AJ. Beyond the bombs: cancer risks of low-dose medical radiation. Lancet. 2012 Aug 4;380(9840):455-7.
  4. Bowden T. Frying one’s gonads for shoes.

Learning from Injury Prevention Researchers

11 Oct, 11 | by Caroline Finch

Image source:

The August 2011 issue of Injury Prevention (sister journal to the BJSM ) included an editorial from me with my views on an apparent unfortunate divide between sports medicine and injury prevention researchers.   The two groups rarely meet at the same conferences or read the same journals and so there is somewhat of a lack of knowledge about relevant research across the two sectors. I have vowed to help reduce this gap by establishing cross-journal Blog posts to directly alert readers of one journal about relevant research in the other, and vice versa.  Of course, my hope is that this will not be necessary in the long-term and that cross-fertilisation of ideas becomes the norm.

In this first IP to BJSM  cross-Blog, I’d like to alert injury researchers to several papers describing methodological issues of relevance, also published in the August IP issue.

One paper by Lawrence discusses the use of the controlled vocabularies of the commonly-used literature search engines PubMed/MEDLINE and PsycINFO for finding articles on injury prevention and safety promotion.  It highlights specific indexing problems that could impact on the quality of literature search strategies that rely solely on those methods to identify papers to include in reviews.

Another paper by Khan et al focuses on the statistical issue of how to best model injury count data, when there are excess zeroes. This is a common occurrence in injury studies where most people sustain no injuries, many only one or two injuries and fewer people sustain more injuries.  Such data should not be analysed by traditional Poisson counts and more appropriate statistical modelling applied instead.

Finally, Cryer et al present a new theoretical definition of injury death, which should overcome the short falls of current surveillance systems which are known to under-enumerate injury deaths.  Even though deaths in sport are rare compared to those in other settings, these new definitions are relevant to anyone who uses routine mortality data to monitor injuries.

Caroline Finch is an injury prevention researcher specialising in implementation and dissemination science applications for sports injury prevention.  She is the Senior Associate Editor for Implementation & Dissemination for the British Journal of Sports Medicine and a member of the Editorial Board of Injury Prevention; both journals are published by the BMJ Group.  Caroline can be followed on Twitter @CarolineFinch

Osteoarthritis Prevention: Important for the Young and Old

5 Mar, 11 | by Karim Khan

In April, our special issue of BJSM reminds athletes, clinicians, and coaches that prevention of osteoarthritis is important for both younger and older athletes. Check these papers online first if you have BJSM access – otherwise they’ll be up on April 1st.

Dennis Caine and Yvonne Golightly review  the epidemiology of OA, the effect of acute injury, epiphysial growth plate injury as well as the link between level of sports participation and OA during childhood. They suggest a link between youth sports injuries (most notably in the knee or ankle) and OA. Thus, efforts to prevent sport-related early-onset OA should begin during the childhood years. (Read full article here)

On the other side of the age spectrum, Jiri Dvorak’s review stems from Klunder et al’s seminal investigation that OA of the hip was significantly more frequent in retired football players than controls.  Dvorak assesses FIFA data on injury prevention programs and injury related drug use. The team found a problem of excessive medication use in top-level female and male international football players. “Research into the early onset of osteoarthritis in sports and in particular the most popular sport, football, should include an early diagnosis of small cartilage lesions in the joints which might be treated and reduce the later onset of osteoarthritis.” (Read full article here)

Hideki Takeda et al. offer a review of OA treatments (in both athletes and non-athletes). Unfortunately, surgical or physical rehabilitation does not preclude OA in the knee, and injury prevention is therefore imperative. (Read full article here)

Thanks to Arthritis Research who sponsored the Arthritis in Sport Conference in London in October 2010 (link to BJSM October 2010)

Thanks to the IOC for their support of 4 IPHP Issues annually – see the April 2011 theme issue for the full set of key papers. This issue will be given free to all the attendees of the IOC World Conference on Prevention of Injury and Illness Prevention in Sport (Monaco, 7-9 April).

Patellofemoral pain syndrome? Consider orthoses or more comfortable shoes!

24 Feb, 11 | by Karim Khan

In the current issue of BJSM, Barton, Menz, and Crossley’s report on The immediate effects of foot orthoses on functional performance in individuals with patellofemoral pain syndrome. Their paper supports the beneficial effects of prefabricated orthoses. Orthoses “provide immediate improvements in functional performance, and these improvements are associated with a more pronated foot type and poorer footwear motion control properties.”

Potential good news for those suffering from knee pain!

Fellow blogger Ian Griffiths weighs in on the discussion of pronation and injury prevention with his recent post: What running shoes should you wear? The myths busted . He also offers a brief, and interesting history of running shoe prescription. 

What do you think about the relationship between foot mechanics and lower limb injury? Is shoe ‘cushioning’ a myth and comfort the most important thing? It’s been a big year for changes in paradigms in this field — Benno Nigg’s work on the mechanisms of action, Irene McClay on barefoot running and new data on orthoses. Exciting times – gotta love new data!

Send us your comments and let us know what works in your clinical practice.

And BJSM is on Twitter @BJSM_BMJ

Role of pacing in speed skating and cycling (see video!): Florentina J Hettinga guest blogs for BJSM

15 Feb, 11 | by Karim Khan

At about this time last year, the Winter Olympics took place in Vancouver.  In my country (the Netherlands) this is a very important event, being raised (or maybe even born if we think of Mark Tuitert, Ireen Wűst and Sven Kramer…) with speed skates on our feet. However, since it is also the year before the 2012 Olympicsin London, where cycling is an important event…it’s a nice time to focus on what we can learn from differences between cycling and speed skating.


Two of our papers on pacing and performance are in the February and March issues of BJSM. We studied (by combining modelling with experimental testing) the importance of pacing in both cycling and speed skating a 1500m distance. Our experiments showed that the best 1500m cycling performances were associated with a high mean power output and a fast start pacing strategy. In addition, using modelling techniques, we found that in all cases, cyclists were very well able to choose a close to optimal pacing strategy based on their ‘form of the day.’ Differences in mean power output were responsible for variations in performance.

In 1500m speed skating, this was different. In contrast to cycling, skaters were further away from optimal performance and there was room to improve performance by adjusting pacing strategy. Unfortunately, skaters who tried this did not succeed — they could perform a slightly faster start, but earlier fatigue associated with their fast start resulted in large consequences on technical aspects of the movement over the race. If speed skaters would succeed in dealing with the earlier fatigue associated with the fast start, models predict they would benefit of a faster start.

A perfect example of this was the Olympic race of Mark Tuitert, who performed the fastest start of all competitors, but was also able to deal with the premature fatigue in the second part of the race: He finished first and won the Olympic gold medal (watch race here).

It seems that cyclists have an adequate performance template on which they accurately adapt their pacing strategy based on their form of the day. It might be very important to develop and train this pacing template by experimenting with different pacing strategies. In speed skating, a cyclic movement largely influenced by technical aspects, there may be room for improvement by moving towards a faster start strategy on the 1500m distance. However, adequate training – that aims at dealing with fatigue over the second part of the race – is  required.

Read full articles online now:

F.J. Hettinga, J.J. de Koning, M. Hulleman, C. Foster. Relative importance of pacing strategy and mean power output in self-paced cycling. Br. J. Sports Med. Published Online First: 22 october 2009.

F.J. Hettinga, J.J. de Koning, L.J.I. Schmidt, A.C. Wind, B. MacIntosh, C. Foster. Optimal pacing strategy: From theoretical modelling to reality in 1500-m speed skating. Br. J. Sports Med. Published Online First: 22 october 2009

Achoooooo! Exercise in the cold season.

12 Nov, 10 | by Karim Khan

Yes, it’s the sound of a sneeze.

This month BBC news health reporter, Michelle Roberts wrote a feature on the  BJSM article titled,  Upper respiratory tract infection is reduced in physically fit and active adults.

David Nieman at the Human Performance Laboratory in North Carolina shows that exercise can prevent a cold. Their study on more than 1000 adults was undertaken over 12 weeks of fall/winter. During this time period, the odds of having a URTI were significantly reduced in those who exercised more and perceived themselves to be healthier.

For a link to the BBC report (which featured earlier this week  as the most shared article!), click here.

Physical Activity Guidelines for the US

5 Oct, 08 | by Karim Khan


On Tuesday, October 7, the U.S. Department of Health and Human Services will launch “The Physical Activity Guidelines for Americans” in Washington, D.C. This occasion marks the first time the federal government has released guidelines on physical activity.

The American College of Sports Medicine (ACSM) formally called for the creation of such guidelines as part of an ACSM health policy conference in 2006 at the National Press Club in Washington. ACSM first published physical activity and public health guidelines with the U.S. Centers for Disease Control and Prevention in 1995, and just last year updated those guidelines in a joint publication with the American Heart Association. And ACSM has been working with Congress to ensure the review and publication of these physical activity guidelines every five years.

ACSM and the American Heart Association will support the new federal guidelines, as they are expected to reflect our previously published recommendations. Both are based on the most relevant science that links physical activity to improved health and wellness. Please look for additional details following the launch to help you in your professional translation and communication of physical activity guidelines.

Physical activity more likely to prevent breast cancer in certain groups

18 May, 08 | by Karim Khan

Physically active women are 25 per cent less likely to get breast cancer, but certain groups are more likely to see these benefits than others — please see link.

The type of activity undertaken, at what time in life and the woman’s body mass index (BMI) will determine how protective the activity is against the disease.

Lean women who play sport or undertake other physically active things in their spare time, especially if they have been through the menopause, have the lowest risk of breast cancer.

The researchers reviewed the literature and analysed 62 studies looking at the impact of physical activity on breast cancer risk. They then examined how breast cancer risk was affected by type of activity, intensity of activity, when in life the activity was performed and other factors.

The most physically active women were least likely to get breast cancer. All types of activity reduced breast cancer risk but recreational activity reduced the risk more than physical activity undertaken as part of a job or looking after the house. Moderate and vigorous activity had equal benefits.

Women who had undertaken a lot of physical activity throughout their life had the lowest risk of breast cancer, and activity performed after the menopause had a greater effect than that performed earlier in life.

Physical activity reduced breast cancer risk in all women except the obese and had the greatest impact in lean women (BMI of less that 22kg/m2).

Women who were mothers, had no family history of breast cancer, were not white also had a reduced risk of breast cancer.

The authors said the way in which physical activity protected against breast cancer was likely to be complex and may involve effects on sex hormones, insulin-related factors, the immune system and other hormone and cellular pathways.

Dr Christine M Friedenreich
Division of Population Health and Information,
Alberta Cancer Board.

New BJSM Paper: “Exercise and Folate on Cognition”

8 May, 08 | by Karim Khan

BJSM Citation:
Walking or vitamin B for cognition in older adults with mild cognitive impairment? A randomized controlled trial.

Authors: Jannique G.Z. van Uffelen, Marijke J.M. Chinapaw, Willem van Mechelen, and Marijke Hopman-Rock
Links to:

Although this study found that exercise improves some aspects of cognitive performance, it also confirmed a recent meta-analysis in concluding that that folic acid supplementation does not significantly benefit cognition. A recent article by our group suggested that much of the relationship between folate levels and cognition may be attributed to exercise because exercise is known to raise folate levels. The current article further reinforces the need for research investigating the interaction of exercise, folate, and cognitive performance.

Balk EM, Raman G, Tatsioni A, Chung M, Lau J, Rosenberg IH. Vitamin B6, B12, and folic acid supplementation and cognitive function: a systematic review of randomized trials. Arch Intern Med 2007; 167(1): 21-30.

Middleton LE, Kirkland SA, Maxwell CJ, Hogan DB, Rockwood K. Exercise: a potential contributing factor to the relationship between folate and dementia. J Am Geriatr Soc 2007; 55(7): 1095-8.

BJSM blog homepage


A peer review journal for health professionals and researchers in sport and exercise medicine. Visit site

Creative Comms logo

Latest from British Journal of Sports Medicine

Latest from British Journal of Sports Medicine