What is important is that coaches must apply the Laws when coaching the game. Referees however must apply the Laws when refereeing at any level of competition. At the Rugby World Cup the post tackle events and the ruck were consistently poorly refereed. Only the tackled player and the tackler(s) are permitted to be off their feet and no one else. In the matter of the scrum that Law prohibits the front rows f...
What is important is that coaches must apply the Laws when coaching the game. Referees however must apply the Laws when refereeing at any level of competition. At the Rugby World Cup the post tackle events and the ruck were consistently poorly refereed. Only the tackled player and the tackler(s) are permitted to be off their feet and no one else. In the matter of the scrum that Law prohibits the front rows from charging towards each other. Another important issue is the repetitive contacts between players in the tackle situation and the scrum which over time develops into chronic tissue damage. Such events have led to instability of the shoulder and the acj joints affecting the tackler and premature degeneration of the cervical spine in front row forwards. The study on post match tackle injuries by Takarada (2003)[1] highlights the effects of the contacts made at the tackle.I believe the tackle law can deserve another update.
References
1.Takarada, Y. (2003). Evaluation of muscle damage after a rugby match with special reference to tackled players. British Journal of Sports Medicine, 37(5), 416-419.
The International Rugby Board. (2007). Laws of the game. Dublin: The International Rugby Board.
Despite the measures you have outlined athletes even of the age group you are referring still get injured. Of the measures you have highlighted I believe is only a part of the strategies to injury in sport. In rugby union a study by Chalmers et al (2004)[1] were of the view that coaches had a significant role to preventing injuries, although there has been no study to address that issue it would seem that ou...
Despite the measures you have outlined athletes even of the age group you are referring still get injured. Of the measures you have highlighted I believe is only a part of the strategies to injury in sport. In rugby union a study by Chalmers et al (2004)[1] were of the view that coaches had a significant role to preventing injuries, although there has been no study to address that issue it would seem that ought to be considered in any injury prevention strategy. In reference to pre season team conditioning, how relevant are the exercises that so many athletes undertake in the off season? For rugby union I would think Sevens rugby would be an appropriate off season programme because the game itself simulates the 15's game in most respects. Furthermore, the strategy must take into account the concept of the game and the application of the Laws, Rules of that code, none of these issues were addressed.
References
1.Chalmers, D. J., Simpson, J. C., & Depree, R. (2004). Tackling Rugby injury: lessons learned from the implementation of a five-year sports injury prevention program. Journal of Science and Medicine in Sport, 7(1), 74-84.
Re:Do you get value for money when you buy an expensive pair of running shoes? [1]
When the ground-force-reaction is measured as a function of time
during running or walking, the result is a function of speed and underfoot
conditions [2]. At any speed, however, the area
under the force-time plot represents the total momentum change during the
stance phase of gait. This cannot be altered by any...
Re:Do you get value for money when you buy an expensive pair of running shoes? [1]
When the ground-force-reaction is measured as a function of time
during running or walking, the result is a function of speed and underfoot
conditions [2]. At any speed, however, the area
under the force-time plot represents the total momentum change during the
stance phase of gait. This cannot be altered by any shoe design, since the
consequence would be that the runner would either rise up into the air or
sink lower and lower with bent knees. At the start of the contact phase,
the centre of mass of the runner is moving downwards. At the end of the
contact phase, the centre of mass is moving upwards – the motion must be
exactly reversed. Attempts to find a design of running shoe that will
alter the ground-force-reaction are doomed to failure for this reason.
It was shown, however, by McMahon & Greene [3]that if the underfoot
compliance were to be chosen in the range 100-200kN/m, then the spike seen
in the GRF-time plot, as a result of heel impact, will not be observed.
The basic premise of Clinghan et al, that changes should be
detectable in the GRF as a result of differences in shoe design between
expensive and inexpensive shoes, may be seen to be one that would not
survive experimental inquiry. In fact, their results were defined before
any tests were carried out, since no differences can be found.
The fact that differences were seen between different areas of the
foot may be put down to experimental variation, and the fact that while
the GRF cannot be changed radically, it is possible to redistribute the
force across the foot.
References
1. Clinghan R T, Arnold G P,Drew T S, Cochrane L, and Abboud R J
Do you get value for money when you buy an expensive pair of running shoes?
Br J Sports Med 2007.038844v1
2.Walker CA & Blair R Leg stiffness and damping factors as a function of
running speed, Sports Engineering 2002, 5, 129-139.
3. McMahon TA & Greene PR The influence of track compliance on
running, J. Biomech. 1979, 12, 893-904.
Being that women are 6-10 times more likely to suffer from knee
injuries or anterior knee pain, perhaps clinical significance would be
improved if mainly females were tested.
In the last issue of the journal, a review of tennis elbow and its
management in tennis players appears. It is disappointing to see that the
journal publishes a review with misleading treatment recommendations. The
review article suffers from the inherent weaknesses of the narrative
review form with an unjustified favourisation of "promising"
pharmacological and surgical interventions. Physical inte...
In the last issue of the journal, a review of tennis elbow and its
management in tennis players appears. It is disappointing to see that the
journal publishes a review with misleading treatment recommendations. The
review article suffers from the inherent weaknesses of the narrative
review form with an unjustified favourisation of "promising"
pharmacological and surgical interventions. Physical interventions are not
even mentioned in the conclusion, and the authors state that there is “no
scientific evidence regarding the efficacy in the long term of the
currently used conservative treatment options”. In addition, they
recommend that “a wait-and-see approach is initially advised, as long-term
results do not differ significantly between groups, but if complaints
persist, a surgical approach can be considered”.
In the treatment section of the review, steroid injections are claimed to
be beneficial in the short term and not significantly different from other
treatments in the long and intermediate term. This statement does not
reflect the available evidence. Physiotherapy is acting faster than wait-and-see with significantly better results at 6 weeks [1], while
physiotherapy is significantly better than steroid injections at 12, 26
and 52 weeks [2]. Thus, from a safety perspective it can be concluded that
steroid injections increase the risk for chronic disability and possible
permanent tendon damage [3]. It remains unanswered whether this negative
effect is reversible or not in a timeframe beyond one year. Consequently,
steroid injections should be discouraged in the management of tennis
elbow.
Regarding surgery, there is a scarcity of randomized controlled trials,
and we found only one randomized trial showing no difference over botox
injections [4]. The self-limiting nature of tennis elbow with scientific
evidence showing a 92% success rate at 1 year after physiotherapy [2],
leaves no place for surgery with the inherent risks and lack of documented
effects in tennis elbow management.
The final word about the contents of an optimal physiotherapy package for
tennis elbow has probably not been said. The review cites two references
with low level laser therapy (LLLT) reviews, which have missed large parts
of the LLLT literature, and fail to address the validity of doses and LLLT
procedures. Three LLLT-trials with positive results which we included in
our 2001 LLLT-review of tendinopathies[5] were omitted from these reviews.
One of the omitted trials showed a significantly positive short-term
effect for LLLT over placebo in recreational tennis players [6]. Another
two LLLT trials with exercise therapy regimens in tennis elbow from 2007
show that the addition of 904 nm LLLT with valid doses provides
significantly faster pain-relief than placebo LLLT and exercises [7, 8].
From the above, modification of sports activity and an active approach
with a physiotherapy package containing exercises, stretching,
mobilisation and possibly LLLT emerges as the new gold standard in tennis
elbow management. There is certainly no need to consider steroid
injections or surgery for the average patient with tennis elbow
complaints, when effective risk-free alternatives exist.
References
1. Bisset, L., et al., Mobilisation with movement and exercise,
corticosteroid injection, or wait and see for tennis elbow: randomised
trial. BMJ, 2006. 333(7575): 939.
2. Bisset, L., et al., Conservative treatments for tennis elbow do
subgroups of patients respond differently? Rheumatology (Oxford), 2007.
46(10): 1601-5.
3. Smidt, N. and D.A. van der Windt, Tennis elbow in primary care.
BMJ, 2006. 333(7575): 927-8.
4. Keizer, S.B., et al., Botulinum toxin injection versus surgical
treatment for tennis elbow: a randomized pilot study. Clin Orthop Relat
Res, 2002(401): 125-31.
5. Bjordal, J., C. Couppé, and A. Ljunggreen, Low level laser therapy
for tendinopathy. Evidence of a dose-response pattern. Physical Therapy
Reviews, 2001. 6(2): 91-99.
6. Palmieri, B., Stratified double blind crossover study on tennis
elbow in young amateur athletes using infrared lasertherapy. Medical Laser
Report, 1984. 1: 1.
7. Lam, L.K. and G.L. Cheing, Effects of 904-nm Low-Level Laser
Therapy in the Management of Lateral Epicondylitis: A Randomized
Controlled Trial. Photomed Laser Surg, 2007. 25(2): 65-71.
8. Stergioulas, A., Effects of low-level laser and plyometric
exercises in the treatment of lateral epicondylitis. Photomed Laser Surg,
2007. 25(3): 205-13.
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.
Lucia and colleagues [1] recently reported a case study in which a
Spanish elite long jumper was identified as being α-actinin-3
deficient, owing to carrying the X/X genotype of the R577X polymorphism in
the ACTN3 gene. The authors suggest that the case provides a “notable”
exception to the idea that ACTN3 represents “the ‘gene for speed’,” taking
out of context a question posed in a recent review b...
Lucia and colleagues [1] recently reported a case study in which a
Spanish elite long jumper was identified as being α-actinin-3
deficient, owing to carrying the X/X genotype of the R577X polymorphism in
the ACTN3 gene. The authors suggest that the case provides a “notable”
exception to the idea that ACTN3 represents “the ‘gene for speed’,” taking
out of context a question posed in a recent review by MacArthur and North
[2]. In their review, MacArthur and North consider the evidence for ACTN3
as ‘a’ potential gene important for muscle power performance, and in fact
emphasize the “subtle effect” and “apparent benefit” for the gene on
performance. Such words reflect the fact that muscle power and power-
related performance are undoubtedly highly complex traits, governed by
multiple genetic and environmental factors [3]. That ACTN3 may be a
contributing gene for speed/power is certainly supported by several
studies [4]. A notable feature of the present case is that it is the only
elite-level strength or power athlete reported to date to be α-
actinin-3 deficient [5, 6], providing indirect support for the hypothesis
that α-actinin-3 is an important contributor to muscle power
performance.
Stephen M. Roth, Ph.D.
Department of Kinesiology
University of Maryland
College Park, MD 20742
References
1. Lucia, A, J Olivan, F Gomez-Gallego, C Santiago, M Montil, and C
Foster. Citius and longius (faster and longer) with no alpha- actinin-3 in
skeletal muscles? Br J Sports Med 2007; 41: 616-617.
2. MacArthur, DG and KN North. A gene for speed? The evolution and
function of alpha-actinin-3. Bioessays 2004; 26(7): 786-95.
3. Beunen, G and M Thomis. Gene powered? Where to go from
heritability (h2) in muscle strength and power? Exerc Sport Sci Rev 2004;
32(4): 148-54.
4. MacArthur, DG and KN North. ACTN3: A genetic influence on muscle
function and athletic performance. Exerc Sport Sci Rev 2007; 35(1): 30-4.
5. Yang, N, DG MacArthur, JP Gulbin, AG Hahn, AH Beggs, S Easteal, et
al. ACTN3 genotype is associated with human elite athletic performance.
Am.J.Hum.Genet. 2003; 73: 627-631.
6. Niemi, AK and K Majamaa. Mitochondrial DNA and ACTN3 genotypes in
Finnish elite endurance and sprint athletes. Eur J Hum Genet 2005; 13(8):
965-9.
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.
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.
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
Dear Editor
What is important is that coaches must apply the Laws when coaching the game. Referees however must apply the Laws when refereeing at any level of competition. At the Rugby World Cup the post tackle events and the ruck were consistently poorly refereed. Only the tackled player and the tackler(s) are permitted to be off their feet and no one else. In the matter of the scrum that Law prohibits the front rows f...
Dear Editor
Despite the measures you have outlined athletes even of the age group you are referring still get injured. Of the measures you have highlighted I believe is only a part of the strategies to injury in sport. In rugby union a study by Chalmers et al (2004)[1] were of the view that coaches had a significant role to preventing injuries, although there has been no study to address that issue it would seem that ou...
Dear editor
Re:Do you get value for money when you buy an expensive pair of running shoes? [1]
When the ground-force-reaction is measured as a function of time during running or walking, the result is a function of speed and underfoot conditions [2]. At any speed, however, the area under the force-time plot represents the total momentum change during the stance phase of gait. This cannot be altered by any...
Dear editor
Being that women are 6-10 times more likely to suffer from knee injuries or anterior knee pain, perhaps clinical significance would be improved if mainly females were tested.
Dear editor
In the last issue of the journal, a review of tennis elbow and its management in tennis players appears. It is disappointing to see that the journal publishes a review with misleading treatment recommendations. The review article suffers from the inherent weaknesses of the narrative review form with an unjustified favourisation of "promising" pharmacological and surgical interventions. Physical inte...
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...
Dear Editor,
Lucia and colleagues [1] recently reported a case study in which a Spanish elite long jumper was identified as being α-actinin-3 deficient, owing to carrying the X/X genotype of the R577X polymorphism in the ACTN3 gene. The authors suggest that the case provides a “notable” exception to the idea that ACTN3 represents “the ‘gene for speed’,” taking out of context a question posed in a recent review b...
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
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 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...
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