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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

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 1^st.

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).

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

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

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.

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.

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.

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

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:
ABSTRACT
ARTICLE

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.

Take a look at this interesting response by Bradley Elliot, Centre de recherche de l’Hôpital Laval, Québec, Canada to Paul Joseph Boyle’s paper “Does occupational success influence longevity among England test cricketers?”

Sir,
I read the recent article by Paul Boyle (Boyle 2008) regarding the longevity of English test cricketers with interest. In this paper the authors linked length of international cricket career (‘success’) with lifespan, suggesting that a successful life lead to a longer life. The hypothesis that quality of life grants one a physiological advantage and therefore increases length of life is well accepted in the medical field and its mechanisms deserve closer examination.

However, I feel that the author has potentially overreached with this conclusion by dismissing the effect of physical activity on lifespan. The author states that the increased levels of physical fitness we would expect in world class athletes are unlikely to affect lifespan because “cricket is not a sport which requires physical strength”. In this conclusion the author has incorrectly regarded fitness as musculoskeletal strength alone, ignoring the important aerobic component. Cricket is primarily an aerobic sport, and the fitness of its players is often underestimated (Noakes and Durandt 2000). Several studies in both animals and humans have demonstrated a link between aerobic activity and lifespan.
Rats subjected to only 10 minutes walking a day live 25% longer than sedentary littermates (Retzlaff et al. 1966). The classic London busmen study (Heady et al. 1956) and several others (reviewed by Warburton et al. 2006) all demonstrated that people who worked in physically active positions lived significantly longer then workmates who had more sedentary positions.

It is reasonable to assume that those who were honored to represent their country for longer had a higher level of physical activity for a longer period of time than those who did not, therefore likely having an effect on longevity.

Bradley Elliott,
Centre de recherche de l’Hôpital Laval, Québec, Canada

Boyle, P. J. (2008). “Does occupational success influence longevity among England test cricketers?” Br J Sports Med: bjsm.2007.041566.

Heady, J. A., J. N. Morris and P. A. Raffle (1956). “Physique of London busmen; epidemiology of uniforms.” Lancet 271(6942): 569-70.

Noakes, T. D. and J. J. Durandt (2000). “Physiological requirements of cricket.” J Sports Sci 18(12): 919-29.

Retzlaff, E., J. Fontaine and W. Furuta (1966). “Effect of daily exercise on life-span of albino rats.” Geriatrics 21(3): 171-7.

Warburton, D. E., C. W. Nicol and S. S. Bredin (2006). “Health benefits of physical activity: the evidence.” Cmaj 174(6): 801-9.