Prof. McCrory was precisely on target in recommending a proactive
reformation in sport and exercise medicine (SEM). He started by outlining
Martin Luther’s seminal declaration of 1517. The analogy is insightful. I
cannot disagree with any of Prof. McCrory’s major points, though I must
highlight some more practical issues concerning access to quality SEM
care.
I am an American completing my PhD in the UK in the...
Prof. McCrory was precisely on target in recommending a proactive
reformation in sport and exercise medicine (SEM). He started by outlining
Martin Luther’s seminal declaration of 1517. The analogy is insightful. I
cannot disagree with any of Prof. McCrory’s major points, though I must
highlight some more practical issues concerning access to quality SEM
care.
I am an American completing my PhD in the UK in the field of dance
medicine. I have spent 27 years working in the fields of sport medicine
and dance medicine as an allied health professional called a Certified
Athletic Trainer (www.nata.org). This professional in the USA (and in a
few other countries, albeit often under a different professional title)
works intimately with medical doctors and other members of a sport
medicine team to provide high quality, comprehensive care to physically
active people.
One of the most significant components of SEM care is orthopaedic
injuries. This care extends from initial at-venue urgent care to
examination, treatment, rehabilitation—and even prevention—of injuries. My
experience and my comparison of this facet of SEM care in the USA and the
UK lead to some very germane points. I hasten to add that this is not a
nationalistic argument; I intend to be constructive in offering my
perspective.
1) Athletes and dancers in the UK with whom I have discussed their
injury care are universally aggravated by an oft-maligned National Health
Service that appears ill-equipped to deliver the prompt and often highly
specialised care athletes and dancers require. Thus, care that is focused
on timely evaluation, treatment, reconditioning and return to activity is
virtually inaccessible for all but the elite and highly skilled
participants who enjoy preferential care systems. (In the UK most
physically active people must sustain a sizeable personal financial cost
to obtain relatively immediate care.) Frankly, this should not be seen as
a castigation of the NHS because such specialised care is not really their
assignment. The finances required of athletes or dancers wanting to
circumvent the NHS in order to secure appropriate and timely care only
exacerbates the frustration. Therefore, the needs of all physically active
people must be considered.
2) Depending entirely on a cadre of SEM medical doctors does not seem
to be the wisest use of resources, nor is it even possible. Prof. McCrory
alludes to this. He identifies an allied health professional when he
comments, “In team sport, much of what happens on the field is first aid
and can be dealt with adequately by an appropriate sports trainer.” I do
not know if “sports trainer” is an officially recognised professional in
the United Kingdom, but without getting unnecessarily hung up on
occupational titles I believe there is significant room for developing a
well-educated, highly qualified contingent of allied health professionals
who actively work with medical doctors in ensuring that physically active
patients receive appropriate evidence-based care starting at their
activity venues. (I am not speaking of a “sports first aider.”)
Furthermore, this need likely exists in any country where sport, exercise
and physical activity are widely practised.
3) The prospect of a new professional to fit a niche in the continuum
of sport and exercise healthcare is a very new—and perhaps
troubling—concept for most medical systems. But, it has met with great
success in countries where it has been implemented. Certainly “turf
battles” are counterproductive to this effort. It requires an emphasis of
“How can we most effectively and efficiently deliver the best possible
care to our patients?” rather than “How are these other people going to
infringe on my work?”
In summary, a real reformation in sports medicine will occur when
people engaged in physical activity enjoy (a) timely access (b) to
appropriate care (c) delivered by a mutually respectful team of healthcare
professionals (d) who are highly qualified in the principles and practise
of sport and exercise medicine. In keeping with Prof. McCrory’s analogy,
consider these four theses as a posting on SEM’s door.
I felt my heart sink as I read this paper. I’m not quite sure why,
but perhaps my response reflected my concern that science and in
particular, exercise science, is at risk of making a fool of itself? It is
increasingly evident that there is a plethora of unorthodox diet and/or
physical activity interventions emerging in conjunction with the global
'threat' of an obesity epidemic.
I felt my heart sink as I read this paper. I’m not quite sure why,
but perhaps my response reflected my concern that science and in
particular, exercise science, is at risk of making a fool of itself? It is
increasingly evident that there is a plethora of unorthodox diet and/or
physical activity interventions emerging in conjunction with the global
'threat' of an obesity epidemic.
The notion of combining exercising and working simultaneously is a
little farfetched. And one must also query the practicalities and safety
of promoting an environment where people exercise while they work. The
risk of falling while walking on a treadmill in front of one's computer,
or even walking around a room reading would need to be carefully
considered. To operate the machine safely and effectively, one would need
to learn new motor skills, and possibly even dose up on medication to
prevent motion illness. Logistically, would it not be somewhat chaotic
attempting to conduct a meeting in which everyone were walking and
working?
Moreover, do we now live in such a ‘high tech’, ‘24-7’ culture that
we cannot find 30-40 minutes or so each day to go for a brisk walk in an
environment away from work? Would the sedentary overweight or obese
population really choose to use the ‘walk-and-work’ desk beyond a few
days? I doubt such individuals would warm to this invention any more than
they would to most other physical activity interventions.
Despite the critical tone of my letter I hold respect for much of
Levine’s research. But the step between biologically-controlled non-exercise activity thermogenesis (NEAT) and forced, voluntary ‘walk while
you work’ exercise seems too great. Perhaps it will ‘catch on’; however I
am currently inclined to add the ‘walk-and-work’ desk to the same category
as the Sinclair C5.
Ogura et al. [1] demonstrated that microwave hyperthermia treatment
increases HSP27, HSP72 and HSP90 content of human skeletal muscle. We have
also employed a passive heating protocol entailing submersion of one limb
(to the level of the gluteal fold) in warm water maintained at
approximately 45°C [2]. Our protocol induced an increase in muscle
temperature to 39.5°C and we failed to observe any increas...
Ogura et al. [1] demonstrated that microwave hyperthermia treatment
increases HSP27, HSP72 and HSP90 content of human skeletal muscle. We have
also employed a passive heating protocol entailing submersion of one limb
(to the level of the gluteal fold) in warm water maintained at
approximately 45°C [2]. Our protocol induced an increase in muscle
temperature to 39.5°C and we failed to observe any increase in alpha B-crystallin, HSP27, HSP60, HSC70 or HSP70 in the vastus lateralis muscle at
48 h post-heating [2]. We therefore suggested that elevations in muscle
temperature per se appear not to be the most important stressor that
induces up-regulation of heat shock proteins (HSPs) following exercise. In
this regard and given that antioxidants abolish the exercise-induced
stress response, we also suggested that exercise-induced reactive oxygen
species (ROS) may act as main signalling molecules. Nevertheless, we did
acknowledge that future research experimenting with differing rates of
heating (which more closely mimic the rate of heating during exercise) was
warranted. Ogura and colleagues have successfully undertaken such a study
and using the technology of microwave hyperthermia have shown that passive
heating to 40°C at a rate similar to exercise can induce increases in HSP
content in human muscle within a time-course similar to individual
responses regarding the exercise-induced induction of HSPs [3]. Although
this finding does not take away from the ‘antioxidant’ exercise related
studies, these data suggest that heat derived radicals may act as the
primary stressors initiating the exercise-induced stress response.
Administration of antioxidants during exercise may therefore scavenge
these heat derived radicals (along with contraction-induced ROS) and
thereby attenuate or abolish the exercise induced production of HSPs. As
such, these data provide new insight as to the mechanisms initiating the
exercise-induced production of HSPs in human skeletal muscle.
References
1. Ogura Y, Naito H, Tsurukawa T, et al. Microwave treatment
increases heat shock proteins in human skeletal muscle. B J Sports Med,
DOI:10.1136/BJSM.2006.032938.
2. Morton JP, MacLaren DPM, Cable NT, et al. Time-course and
differential expression of the major heat shock protein families in human
skeletal muscle. J Appl Physiol 2006, 101, 176-182.
3. Morton JP, MacLaren DPM, Cable NT, et al. Elevated core and muscle
temperature to levels comparable to exercise do not increase heat shock
protein content of skeletal muscle of physically active men. Acta Physiol
2007,DOI: 10.1111/j.1748-1716.2007.01711.x.
We wish to congratulate Professor Hopkins on his article [1]
discussing the link between malignant hyperthermia and exertional heat
illness.
In his commentary on the article Frank Wappler raises the suggestion
that it would be desirable to develop guidelines for investigating
patients with exertional heat illness, and we would like to highlight to
the readership that such guidelines have...
We wish to congratulate Professor Hopkins on his article [1]
discussing the link between malignant hyperthermia and exertional heat
illness.
In his commentary on the article Frank Wappler raises the suggestion
that it would be desirable to develop guidelines for investigating
patients with exertional heat illness, and we would like to highlight to
the readership that such guidelines have already been developed and are in
use in the UK military . These discuss the prevention of heat illness, its
treatment and onward referral by unit medical staff to the Heat Illness
Clinic at the Institute of Naval Medicine (INM) for further investigation
following their recovery.
This investigation seeks to identify the small minority of
individuals who are unable to thermoregulate and exclude those with
underlying medical problems. In only a small number of these individuals
may a susceptibility to malignant hyperthermia be the cause.
Environmental factors are considered and taken into account during
the planning of military training, exercises and operations[2].The
combination of physical activity and military protective clothing raises
the risks of heat strain and heat illness and this risk is elevated
further when combined with hot and or humid conditions. For an individual
who has an underlying susceptibility to heat illness the demand of many
occupations within the military put them at significant risk and may
therefore not be compatible with a continued career.
There are numerous other factors such as level of aerobic fitness,
obesity, skin disorders, disorders of sweating, recent illness, alcohol
consumption, dehydration, medications, sleep deprivation, clothing,
environment and activity level and duration that are implicated in
episodes of exertional heat illness and it has been recognised by the
Armed Forces that the identification of individuals with a predisposition
to heat illness is of operational importance.
The Environmental Medicine Unit at the INM has systematically
investigated military patients since 2001. The assessment comprises
measurement of the patients VO2 max prior to them undertaking a
standardised exercise bout at 60% of VO2 max in a warm environment (34 °C
and 40% Relative Humidity).
To our knowledge the Israeli Defence Force (IDF) is the only other
institution which is known to regularly investigate military personnel for
a history of heat illness [3]. The function of the IDF assessment is also
to investigate thermoregulation in personnel who have suffered an episode
of heat illness. However there are differences in the two protocols: the
IDF assessment involves 2 hours of exercise at a low rate but under higher
environmental heat stress, compared to the INM procedure.
Since its inception, the clinic at INM has examined cases of
exertional heat injury in order to determine any heat intolerance or other
underlying medical condition. However, there remains a requirement to
investigate the link between heat intolerant individuals and their
susceptibility to malignant hyperthermia.
Limited information for patients attending thermal medicine clinics
can be found on the Royal Navy website by following the link below.
We thank Prof. Malina for his interest in our paper.
In most sports, the performance of adolescent athletes is determined by
their physical maturity and thus related to age. In order to guarantee
equal chances for different age groups, age-related tournaments for male
and female players have been established in football. However, due to the
fact that registration at birth is not co...
We thank Prof. Malina for his interest in our paper.
In most sports, the performance of adolescent athletes is determined by
their physical maturity and thus related to age. In order to guarantee
equal chances for different age groups, age-related tournaments for male
and female players have been established in football. However, due to the
fact that registration at birth is not compulsory in some African and
Asian countries, other methods of age determination are needed to prevent
participation in the incorrect age group.
The determination of skeletal maturity using standard radiographs of
the left wrist is an established method in pediatrics, whatever grading
method is used (Greulich-Pyle, Tanner- Whitehouse, Fels). However, in
sports the use of X-rays to determine players of over age is not allowed
because of the exposure to radiation following the guidelines of the IAEA
(International Atomic Energy Agency) which regulates the use and possible
abuse of X-rays under the title: The International Basic Safety Standards
for Protection against Ionizing Radiation and the Safety of Radiation
Sources. The objective and aims of our presented papers (Dvorak et al.
2007a,b) were to develop a grading system for epiphysial fusion based on
MRI of the wrist, to evaluate the reliability and validity of the grading
system in 14-19 year-old football players, to compare male football
players from different ethnic groups, and finally to examine football
players of FIFA and AFC U-17 competitions. In both papers we concluded
that MRI of the wrist is a reliable, valid, and non-invasive method for
age determination in the groups of 14-19 year-old male football players
(to establish the normative values we used young football players with
absolute certainty of birth certification).
Based on the results, it seems that U-17 players are more mature than
football players of the same age from the normative group from
Switzerland, Malaysia, Algeria, and Argentina. However, the lack of
correlation between age category and degree of fusion in U-17 players
supports the suspicion that the age stated in the official documents of
the examined U-17 players might not be correct in all cases. Furthermore,
a drop in the rate of completely fused players was observed between the
first and second competition under investigation (FIFA: from 2003 to 2005,
AFC: from 2004 to 2006). It can only be hypothesized that this decrease is
due to the fact that the team managers of the national associations were
aware the controls were going to be carried out and more careful selection
was consequently carried out. The authors are of the opinion that the
method proposed by using MRI is not only reliable from a scientific point
of view but that it also works as an educational tool to combat cheating
in sport.
Unfortunately, relying on the honesty of trainers and players as
suggested by Professor Malina does not work. To the contrary, the
desirable influence of the MR method on player selection has been
demonstrated by our companion paper (Dvorak et al. 2007b).
J. Dvorak, J. George, A. Junge, J. Hodler
References
Dvorak J, George J, Junge A, Hodler J (2007a) Age Determination by
Magnetic Resonance Imaging of Wrist in Adolescent Male Football Players.
Br J Sports Med 41(1):45-52
Dvorak J, George J, Junge A, Hodler J (2007b) Application of Magnetic
Resonance Imaging of the Wrist for Age Determination in International U-17
Soccer Competitions. British J Sports Med Mar 8; [Epub ahead of print]
Cricket is a unique game characterized by bursts of variable
intensity at unpredictable times. As a retired First-Class cricketer of
six years experience, I was drawn towards this article [1]; exploring the
benefits the introduction of full-body compression garments might offer
cricketers who have to deal with the physiological challenges presented.
Cricket is a unique game characterized by bursts of variable
intensity at unpredictable times. As a retired First-Class cricketer of
six years experience, I was drawn towards this article [1]; exploring the
benefits the introduction of full-body compression garments might offer
cricketers who have to deal with the physiological challenges presented.
The particular choice of running test and the introduction of a
measured throw were thoughtful research tools in a study of cricketers; at
which point I feel the article veers away from the characteristics of the
game.
Firstly the design of the trial had the participants performing the
tests “72-96h apart, while abstaining from caffeine, alcohol and food 3h
before testing” whereas first-class cricket is played over three, four or
five days, to use England as an example, for four to five days per week.
The only significant findings in the study were the differences in
24h post-exercise CK, 24h ratings of muscle soreness and (unsurprisingly)
skin temperature. There was no significant difference between the repeat-sprint or throwing performances either across types of garment, or against
the control. This is surely predictable after 3-4 days rest.
With re-design this study could well answer the questions it set out to,
in a format more consistent to a cricket environment.
I would suggest running the tests twice or three times per day, to
imitate the sessions within the game, for three days. Post-exercise CK
measurements and ratings of muscle soreness would be best taken each day
before exercise begins, and importantly comparison could be made of the
performance change over time in the already validated tests. This would
most likely demonstrate that cricketing performance is hindered by muscle
damage and perceived discomfort, and any advantage or not, from the
garments would be demonstrated by rigorous sport specific testing.
References
1. Comparison of three types of full-body compression garments on
throwing and repeat-sprint performance in cricket players. Br J Sports Med
2007; 41: 409-414
Thank-you for the letter and interest in the research on compression
garments we recently published in BJSM (and apologies for the delayed
response – conference and holiday time!). Further, we appreciate the
comments and required clarification of the specificity of the research
design in relation to cricket. As with the English system, in Australia
cricket matches are also conducted over both sing...
Thank-you for the letter and interest in the research on compression
garments we recently published in BJSM (and apologies for the delayed
response – conference and holiday time!). Further, we appreciate the
comments and required clarification of the specificity of the research
design in relation to cricket. As with the English system, in Australia
cricket matches are also conducted over both singular and multiple
(consecutive) days of play. However, this is where some misunderstanding
of the intention of the research project may have occurred, as it was not
the intention of the authors to directly simulate game play or replicate
match demands or the associated effects of compression garments on cricket
matches. Rather it was the intention of the authors to determine the
effects of the compression garments on performance and physiological
parameters associated with upper- and lower-body intermittent-sprint
exercise, as would be used by athletes in training or competition with a
focus on cricket players (who use both upper and lower-body).
Currently there is no published literature on cricket match demands
(although we have a manuscript in-review on the time-motion analysis of
Test and One-Day International matches which is likely to be the first
data published on this topic), which makes the quantification and
validation of any exercise protocol attempting to replicate cricket
demands difficult. Further, while the type of activity pattern used in the
current exercise protocol may not specifically replicate the demands of a
cricket match, it is however, generic to the type of intermittent-sprint
patterns found in physical conditioning and training programs in both
cricket and other repeat-sprint sports. Hence, while the exercise may not
specifically replicate game demands, it does replicate the high-intensity
demands of many training programs (during which compression garments are
often worn). Additionally, this was also an aspect of the study that was
important to us; to allow for a larger scale application of the use of
compression garments to sports other than just cricket. Finally, the
exercise protocol used here has previously been reported to be sensitive
enough to elucidate small changes in exercise performance resulting from
different interventions or conditions imposed (as reported in a paper we
have published in EJAP on pre-cooling procedures: Duffield and Marino
2007). Therefore, as outlined, while the exercise protocol utilised was
not specifically indicative of the demands of a cricket match, as there is
currently no information on what those match demands are, combined with
the greater applicability to a range of sports of a generic intermittent-
sprint protocol used in training and conditioning scenarios (which is
sensitive enough to detect changes in both maximal and sub-maximal
performance), we feel this option best served both the cricketing and
larger team-sports communities.
In response to other suggestions and comments, the 72-96 h with
avoidance of exercise, food and caffeine is standard methodological
research design when using any randomised, cross-over design research.
Given (for the above reasons) we chose a 30-min generic intermittent-
sprint exercise protocol, in order to ensure there were no effects of the
exercise in one condition (garment) on the next, a sufficient ‘wash-out’
period is required to ensure any delayed soreness or elevated CK was not
present in baseline measures of the next condition. Hence, again, while
this may not replicate demands of consecutive day cricket, it is what is
required for maintenance of research integrity. The design of the study
was to determine the acute effects of compression garments on a bout of
high-intensity exercise; hence the 3-4 days rest was not of relevance to
the determination of effects of comparison of performance on cricket
matches, however allowed a return to a resting baseline for all
physiological measures in all respective conditions.
As indicated in your letter, results published in our paper reported
a reduction in 24 h post-exercise CK and perceived muscle soreness which
may indicate the usefulness of the garments to prepare players for
training or game demands the following day (improved recovery). The
suggestion to perform testing involving consecutive day exercise is a good
idea; however, we have already performed similar testing in rugby players
with similar results to the current study. Regardless of improved ratings
of muscle soreness or reduced CK values, neither of these parameters have
any direct association with performance in intermittent-sprint exercise.
As such, this further research we have performed highlights this during
exercise protocols that induce higher metabolic, physiological and
contusion loads than would be found in cricket; however, still resulted in
minimal ergogenic benefits of the garments on repeated bouts over
consecutive days of exercise. Further, given the limited evidence of the
role in elevated CK or perceptual measures accounting for performance
changes, and little other evidence of the effect of compression garments
on any other physiological functioning in healthy athletic populations, it
is currently equivocal that compression garments provide performance
benefit in intermittent-sprint activity. Finally, as is well stated in
your e-letter, that while it may be unsurprising skin temperature was
higher under the respective garments, a perusal of many compression
garment web-sites will reveal that this is the opposite to how the
garments are being advertised and sold (and in essence are being marketed
in contradiction of normal thermoregulatory functioning of the body!).
In conclusion, while we appreciate the suggestions provided, the main
idea proposed (consecutive day exercise protocol with performance
measures) has already been performed, with no indication that exercise
performance (speed, power, strength or aerobic ability) is improved when
wearing compression garments during single or consecutive days of
intermittent-sprint exercise. Further, the current study was designed as a
more generic investigation using cricket players (who engage in both upper
- and lower-body intermittent exercise) rather than on cricket per se.
Regards
Rob Duffield, PhD
School of Human Movement, Charles Sturt University
Firstly I think the authors of this article are to be congratulated
for condensing a significant amount of information to a digestible article
of interest to clinicians and investigators alike. The investigators point
out that many examination techniques fail to repeat the initial success of
their investigation during subsequent study by other authors. One aspect
of this oft-cited point which has evaded...
Firstly I think the authors of this article are to be congratulated
for condensing a significant amount of information to a digestible article
of interest to clinicians and investigators alike. The investigators point
out that many examination techniques fail to repeat the initial success of
their investigation during subsequent study by other authors. One aspect
of this oft-cited point which has evaded attention may be failure to
perform the physical examination in the same manner. For example, in the
original description of the Active Compression Sign[1], the OST is
described thus:
‘The patient was asked to forward flex the affected arm 90° with the
elbow in full extension. The patient then adducted the arm 10° to 15°
medial to the sagittal plane of the body. The arm was internally rotated
so that the thumb pointed downward. The examiner then applied a uniform
downward force to the arm. With the arm in the same position, the palm was
then fully supinated and the maneuver was repeated.’ (p. 610).
The Active Compression sign has been re-investigated by Parentis et
al[2] who describe the test somewhat differently as follows:
‘To perform this test, the shoulder is forward flexed to 90° and
adducted 10° to 15°. The shoulder is then fully internally rotated, and
the patient is asked to resist downward pressure on the arm by the
examiner. The test is then repeated with the shoulder in the fully
externally rotated position’[2] (p. 410)
Similarly Parentis et al[3] describe the Active Compression sign:
‘The active compression test was performed with the patient standing.
The shoulder was flexed forward to 90° and adducted 10° while the elbow
was fully extended. The shoulder was then fully internally rotated. A
downward force was applied, and the patient was asked to resist. This
motion was then repeated with the shoulder externally rotated.’[3] (p.
266)
Significantly in the original description the shoulder position is
maintained constant whilst the degree of forearm supination is the only
alteration in re-performing the second part of the test whilst the two
subsequent investigations make no such distinction altering shoulder
position in the second portion of the test. Intuitively the Active
Compression Sign has utility in the examination of long head of the biceps
origin injury since the patient’s pain behaviour is described by altering
only the forearm pronation/supination and therefore perhaps altering the
amount of tension on the long head of the biceps but little else at the
shoulder joint. This would seem to have similarity with a number of other
examination techniques directed toward biceps anchor pathology such as The
Biceps Load Test[4], The Biceps Load II[5], the ‘New Pain Provocation
Sign’[6], and the ‘SLAP prehension’ test[7]
Comparing the original examination[1] with subsequent tests[2, 3]
which do not accurately reproduce the test is simply not ‘comparing apples
with apples’. I’d suggest that a vital addition to the checklist of
diagnostic accuracy is ensuring accurate performance of the test as
originally described before between-test examination can be conducted.
References
1. O'Brien, S.J., et al., The active compression test: a new and
effective test for diagnosing labral tears and acromioclavicular joint
abnormality. Am J Sports Med, 1998. 26(5): p. 610-3.
2. Parentis, M.A., et al., An anatomic evaluation of the active
compression test. J Shoulder Elbow Surg, 2004. 13(4): p. 410-6.
3. Parentis, M.A., et al., An evaluation of the provocative tests for
superior labral anterior posterior lesions. Am J Sports Med, 2006. 34(2):
p. 265-8.
4. Kim, S.H., K.I. Ha, and K.Y. Han, Biceps load test: a clinical
test for superior labrum anterior and posterior lesions in shoulders with
recurrent anterior dislocations. Am J Sports Med, 1999. 27(3): p. 300-3.
5. Kim, S.H., et al., Biceps load test II: A clinical test for SLAP
lesions of the shoulder. Arthroscopy, 2001. 17(2): p. 160-4.
6. Mimori, K., et al., A new pain provocation test for superior
labral tears of the shoulder. Am J Sports Med, 1999. 27(2): p. 137-42.
7. Berg, E.E. and J.V. Ciullo, A clinical test for superior glenoid
labral or 'SLAP' lesions. Clin J Sport Med, 1998. 8(2): p. 121-3.
We are writing to comment on, Mechanisms of non-contact ACL injuries,
by Yu and Garrett [Yu and Garrett (2007)]. Through what we consider to be a less than
comprehensive review, the authors conclude that “valgus” could not be a
mechanism associated with ACL rupture and therefore imply that it is not
important to incorporate methods to prevent valgus loading into
neuromuscular training programs...
We are writing to comment on, Mechanisms of non-contact ACL injuries,
by Yu and Garrett [Yu and Garrett (2007)]. Through what we consider to be a less than
comprehensive review, the authors conclude that “valgus” could not be a
mechanism associated with ACL rupture and therefore imply that it is not
important to incorporate methods to prevent valgus loading into
neuromuscular training programs to prevent ACL injury. For example,
Yu and Garrett attempt to rebuff the idea that “valgus” is associated with
isolated ACL injury. In particular, the authors question the validity of
the Hewett 2005 AJSM study because they don't believe that “valgus” can
cause ACL injuries. That is not, however, what the Hewett et al. study
reported. Through rigorous experimental analysis, an association between a
prospectively measured variable, knee abduction torque, and ACL injury was
observed. One can, of course, interpret these observations in different
ways, but the statistical and clinical significance of this association is
well established in the peer-reviewed literature.
It is our working hypothesis that ACL injury likely stems from a
complex three dimensional knee joint load state, encompassing more than
simply anterior shear, knee abduction torque or a “valgus” mechanism. The
load sharing between knee ligaments is complex and it seems plausible that
anterior shear force and axial rotation torque also contribute to the
resultant ACL loading during the “valgus” collapse of the knee so often
observed during injury, especially in female athletes. The authors fail to
include in their review the many published studies that dispute their
point of view. For example, modeling work by McLean et al. and Shin et
al. and cadaver studies by Withrow et al., among many others, are not
cited. Why do the authors choose to ignore such strong evidence when reviewing the existing evidence regarding the
mechanism of ACL injury? Is it because they are absolutely convinced that
it occurs by their hypothesized mechanism (anterior shear arising from the
quadriceps)? It is unlikely that
the mechanism of injury involves only a single plane of motion.
It should be pointed out that in our view methodological flaws also undermine the
credibility of this review. There are, for example, flaws in the authors’
calculations. Specifically, they failed to consider acceleration due to
gravity when calculating average body weight. In their review, Yu and
Garrett state that "...we may have to be cautious when interpreting the
association of knee valgus angle and moment with non-contact ACL injuries
observed in the study by Hewett et al." The association these authors
"cautioned” against was shown in the scatter plot of external knee
abduction moment versus injury status (Figure 9, Hewett et al. 2005). They
took the highest peak external knee abduction (valgus) moment presented in
the scatter plot, removed the normalization to body weight and calculated
the absolute magnitude of external knee abduction in Newton-meters (N-m).
However, they incorrectly calculated an “average” value of 12.5 Nm based
on this single data point. Their error in calculation was that they did
not compute the weight in Newtons, but incorrectly used body mass (in
kilograms). If calculated correctly, the authors would have determined
that the resultant external knee moment was actually 122.6 Nm for that
subject, a value an order of magnitude higher. It is unclear how these
authors published such an erroneous calculation, especially
since Hewett et al. (2005) clearly describe in the text of their article
that females who subsequently suffered ACL injury had an average maximum
external knee abduction moment of 45.3 N-m compared to a value in
uninjured athletes of 18.4 N-m. Another serious methodological flaw is
the authors’ misinterpretation of the “peak resultant proximal tibia
anterior shear force.” As described in Letters to the Editor of AJSM
(2006), Chappell and Yu described an internal force that must be present
to counteract the externally applied proximal tibia posterior shear force.
This external force is a direct consequence of the posterior ground
reaction force, but the authors seem to willfully ignore this effect,
instead focusing solely on the moment that must be counteracted by
quadriceps activity. As further described by Shin et al. (2007) this
posterior shear force actually protects the ACL, rather than endangering
the ACL as the authors claim.
As a collective group, spanning several disciplines and research
institutions, we are concerned with such incorrect citation of
the published literature and the apparent bias of these authors against a
coronal plane contribution to the loading mechanism for ACL injury. Their
review undermines the likely important coronal plane contribution to the
ACL injury mechanism, its potential use to predict those at risk for ACL
injury and its incorporation into programs designed to decrease injury
risk could seriously hamper prevention efforts.
These biased efforts
stifle the pursuit of good science and mislead the less well informed
reader. While we understand that bias may be inherent in the scientific
process, as a scientific community we must strive to review the existing
literature with systematic rigor and the least bias possible.
I read the paper by Torres-Bugarin et al with great interest.
Unfortunately, anabolic androgenic steroids (AAS) are frequently used in
professional, and even in amateur sports. Hence, the aim of the study is
very important.
But before final decision concerning genotoxic activity of AAS, studied by
means of micronucleus (MN) assay exfoliated buccal cells, some very
important points of the paper must be...
I read the paper by Torres-Bugarin et al with great interest.
Unfortunately, anabolic androgenic steroids (AAS) are frequently used in
professional, and even in amateur sports. Hence, the aim of the study is
very important.
But before final decision concerning genotoxic activity of AAS, studied by
means of micronucleus (MN) assay exfoliated buccal cells, some very
important points of the paper must be clarified. And of course, in all
cases the decision could not be final because only 5 bodybuilders were
included in the study.
First of all, the design of the study is not clear, eg. when the
sportsmen started to use the AAS. As I understand it they started to consume
the anabolics after week 1. In this case the number of cells with MN (CMN)
is two-fold higher in consumers that in the control group (1.1 vs. 0.5).
Did the athletes use AAS before? If yes, the study is not valid. If no,
the authors must explain why in the group of AAS consumers before the
start of the study the number of CMN is significantly higher (I calculated
the difference using GraphPrism, p value is equal to 0.0087, Mann-Whitney
test with Gaussian approximation).
If I understand the article rightly, the athletes started to consume the
AAS after the 1st week when they had the level of CMN equal to 1.1‰. Just
after one week the number of CMN increased to 4.8‰ – 4.3-fold. On page
592 it is written that MN in exfoliated cells “can reflect the damage
occurring during the of 3 weeks” (!!). In this case after ONE week of
consumption of AAS such a strike was registered which is suspicious.
The second thing is that in Table 2 some numbers are strange, e.g. 1.3,
6.3 and 6.8. How could the authors obtain such figures in case of studying
2000 cells? The numbers must be either whole numbers or half numbers, eg. 0.5, 7.5 and so on.
Figure 1 depicts CMN, according to the authors. But careful examination of the figure showed that MN in attached to main nucleus. With very high probability it mustn’t be considered as MN and it ought to be considered as a nuclear bud.
The authors wrote that “The scoring was done according to the criterion
established by Torres-Bugarin et al 19(page 593, Sample analysis). But in
the mentioned paper it says that the criterion was established by Page
et al.
Very unsuccessful expressions are used by the authors. The example is
written in the conclusions (What this study adds, page 595) – “The frequency
of MN cells is increased in bodybuilders by AAS, leading to in situ or
systemic loss or DNA damage”. It is completely unclear what the authors
meant.
Another example is “Exfoliated cells are also biomarkers of genotoxicity,
with the advantage that they do not need to be kept in vivo” (page 592). I
could not understand the meaning of this sentence even after reading it many
times.
In conclusion, this is a very interesting paper but there are many errors
and shortcomings which can confuse the readers of the journal. Hence,
they must be clarified as soon as possible.
Prof. McCrory was precisely on target in recommending a proactive reformation in sport and exercise medicine (SEM). He started by outlining Martin Luther’s seminal declaration of 1517. The analogy is insightful. I cannot disagree with any of Prof. McCrory’s major points, though I must highlight some more practical issues concerning access to quality SEM care.
I am an American completing my PhD in the UK in the...
Dear Editor
I felt my heart sink as I read this paper. I’m not quite sure why, but perhaps my response reflected my concern that science and in particular, exercise science, is at risk of making a fool of itself? It is increasingly evident that there is a plethora of unorthodox diet and/or physical activity interventions emerging in conjunction with the global 'threat' of an obesity epidemic.
The notion...
Dear Editor
Ogura et al. [1] demonstrated that microwave hyperthermia treatment increases HSP27, HSP72 and HSP90 content of human skeletal muscle. We have also employed a passive heating protocol entailing submersion of one limb (to the level of the gluteal fold) in warm water maintained at approximately 45°C [2]. Our protocol induced an increase in muscle temperature to 39.5°C and we failed to observe any increas...
Dear Editor
We wish to congratulate Professor Hopkins on his article [1] discussing the link between malignant hyperthermia and exertional heat illness.
In his commentary on the article Frank Wappler raises the suggestion that it would be desirable to develop guidelines for investigating patients with exertional heat illness, and we would like to highlight to the readership that such guidelines have...
Yes, it does work Prof. Malina
We thank Prof. Malina for his interest in our paper. In most sports, the performance of adolescent athletes is determined by their physical maturity and thus related to age. In order to guarantee equal chances for different age groups, age-related tournaments for male and female players have been established in football. However, due to the fact that registration at birth is not co...
Dear Sir,
Cricket is a unique game characterized by bursts of variable intensity at unpredictable times. As a retired First-Class cricketer of six years experience, I was drawn towards this article [1]; exploring the benefits the introduction of full-body compression garments might offer cricketers who have to deal with the physiological challenges presented.
The particular choice of running test and...
Dear Dr Maher
Thank-you for the letter and interest in the research on compression garments we recently published in BJSM (and apologies for the delayed response – conference and holiday time!). Further, we appreciate the comments and required clarification of the specificity of the research design in relation to cricket. As with the English system, in Australia cricket matches are also conducted over both sing...
Dear Editor
Firstly I think the authors of this article are to be congratulated for condensing a significant amount of information to a digestible article of interest to clinicians and investigators alike. The investigators point out that many examination techniques fail to repeat the initial success of their investigation during subsequent study by other authors. One aspect of this oft-cited point which has evaded...
Dear Dr. McCrory,
We are writing to comment on, Mechanisms of non-contact ACL injuries, by Yu and Garrett [Yu and Garrett (2007)]. Through what we consider to be a less than comprehensive review, the authors conclude that “valgus” could not be a mechanism associated with ACL rupture and therefore imply that it is not important to incorporate methods to prevent valgus loading into neuromuscular training programs...
Dear Editor,
I read the paper by Torres-Bugarin et al with great interest. Unfortunately, anabolic androgenic steroids (AAS) are frequently used in professional, and even in amateur sports. Hence, the aim of the study is very important. But before final decision concerning genotoxic activity of AAS, studied by means of micronucleus (MN) assay exfoliated buccal cells, some very important points of the paper must be...
Pages