The 2008 Pre-Olympic Conference on Science, Education and Medicine in Sport Patria A Hume1, Stephen D Kara2, Liesel Geertsema3 and Celeste Geertsema4 Sportscience 12, 31-40, 2008 (sportsci
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The inaugural Pre-Olympic conference
incorporating the Federation of International Sports Medicine (FIMS), the
International Para-Olympic Committee (IPC), the International Council for
Sports Science and Physical Education (ICSSPE) and the International Olympic
Committee (IOC), was held in Guangzhou, China at the Oriental Convention
Hotel from 1-5 August 2008. The convention centre covered one-third of a
square kilometer and was six stories high.
It took more than ten minutes to walk from one end of the exhibition
centre to the other, so you had to be well prepared for the sessions you
wanted to see. The Chinese experience involved communication, dietary, and
other cultural differences as well as Olympic security, as this was viewed as
an additional Olympic venue. The
five-day conference was a combination of 12 keynote addresses, 32
symposia, oral and posters presentations. Of the 3400 submitted abstracts,
371 were podium and 998 were poster presentations. There were usually 10 concurrent streams to
choose from each day of the conference.
Streams covered a wide range of topics in the discipline areas of
sport and exercise science, sports medicine, physical education and
sports-related social science. The
combined nature of this conference attracted attendees from very different
realms in the sporting world: scientists, ethicists, practitioners,
administrators, therapists, and philosophers. Overall, the quality of the
free communications and posters was inferior compared with those at other
international conferences, but the symposia were good. Here
are the highlights… • Reduction of lower limb injuries (ankle sprain, non contact ACL rupture and hamstring strain) can be achieved with structured supervised regular pre-habilitation and rehabilitation plans. • Talent identification programs should include motivation of the player, as motivation correlates with additional play and training not led by the coach, leading to performance improvement. • Implicit learning models are finding increasing popularity, as they potentially provide less destabilization when a player is in competition. • Training the elite child athlete is the topic of a useful IOC consensus statement. •
Practical information and
research on reducing risk of athletic injury
is available from the website of the Oslo Sports Trauma Research
Centre. • Strength training in the elderly population counters the effect of muscle wasting, but maintaining adherence is the challenge. • The IOC Diploma in Sports Nutrition, a two-year distance-learning program coordinated by Ron Maughan, Susan Shirreffs and Louise Burke, was promoted in several sessions. Biomechanics
The
biomechanics theme included presentations on methodology, analysis of
movements and elements, mechanisms of strength training, biomechanics
analysis of sports injury and rehabilitation. Yue Yan Chan (The Chinese University of Hong Kong) showed a new mechanical supination sprain
simulator that has a rotating platform to allow plantar flexion,
dorsiflexion or a combined motion.
Unfortunately the device does not allow control of the tilt range of
motion. Man-Ling Chung (The Chinese University of Hong Kong) then reported on an experimental study that showed that the Air-stirrup ankle brace reduced and delayed
ankle joint motion during a simulated ankle supination sprain on
the simple free-fall mechanical supination sprain simulator. The brace may be
effective in protecting the ankle from sprain injury, as it restricts and
delays the spraining motion. Tik Pai
Fong (The Chinese University of Hong Kong) presented a case study from the
lab where a person had sustained a grade-1 sprain during testing. There was a
higher loading rate at the heel initially with transfer to the forefoot. It was surprising that the ankle sprain
occurred in dorsiflexion rather than the usual mechanism of plantar flexion
and inversion. It was suggested that the heel should be down during landing
to avoid ankle sprain. Corey Scholes (Queensland University of Technology, Australia) outlined the regulation of
sagittal knee stiffness and the test-retest variation in
stiffness. Twelve healthy male volunteers performed 60
step-down landings from a knee-high platform with one minute rest between
trials. It was concluded that some individuals may increase or decrease
landing stiffness to a preferred level during repeated trials without the
presence of external feedback. Mak Ham
Lam presented a review of literature on the biomechanics technique to
evaluate knee
rotation stability. The
findings provide an overview of knee rotational stability measuring
techniques for orthopedic specialists and sport biomechanists to choose the
most suitable protocol for specific application, for example, to evaluate the
surgical outcome of anatomical double-bundle anterior cruciate ligament
reconstruction. Sports NutritionRon
Maughan (Loughborough University, UK) chaired the sports nutrition symposium
that included speakers Susan Shirreffs (Loughborough) and Stephen Wong
(Chinese University of Hong Kong).
Although no new information was presented the following summarizes the
content from the presentations: • The Maughan Rule to supplementation is “if it works then it is probably banned, and if it is not banned then it probably does not work!” • Athletes can obtain their nutritional requirements from a balanced diet ensuring that the essentials of carbohydrate, protein, fat, vitamins, minerals, fiber and water are attended to. • Carbohydrate intake guidelines of 5-7 g/kg body mass in moderate training and up to 10 g/kg during heavy training. • Protein intakes >1.7 g/kg/day are not necessary. • Energy intake is best measured by monitoring body weight and skin folds. • Acute post-exercise creatine supplementation and high carbohydrate intake increases muscle glycogen at three and six days post exercise. • 2% body mass loss (as a measure of hydration status) is the level above which detrimental performance effects will occur, but this figure may be less if heat is involved. (especially temperature >30ºC) • Replace fluid losses at 150% of weight loss. (We note that this percentage is contentious given the possible risk of hyponatremia). • The effectiveness of fluid replacement is improved with higher concentrations of Na+, which can be obtained from rehydration fluids (although Na+ concentration is limited by palatability) or food. K+ concentration is not an issue. • Individualize fluid and recovery regimens • Pre-match meals consisting of low glycemic index foods sustain carbohydrate availability and maintain blood glucose levels during exercise. • Post-game glycogen repletion is best achieved with high-glycemic index foods. Body CompositionPatricia Wong (Nangyang University, Singapore)
described how obesity affects the
relationship between functional capacity and C-reactive
protein in male adolescents in Singapore. Statistically significant differences in
C-reactive protein level, lipid profiles, body composition and functional
capacity between obese and normal-weight adolescents were observed.
Improvement in functional capacity may be a useful intervention in lowering C-reactive protein levels for the
obese individuals, thereby ameliorating the inflammatory status, with or
without substantial weight loss. Yin, Zenong (University of Texas, USA) reported
effects of physical activity frequency
and adiposity level on body composition and fitness in children. Moderate-vigorous
physical activity for at least 60 minutes on most days of the week was associated
with favorable changes in body composition and fitness in 604 students from
18 elementary schools. Faradjzadeh Shahram (National Olympic and Paralympic Academy, Iran) presented the somatotype and body composition of 45
Iranian men’s wushu, tae kwon do, wrestling, judo, and karate national team
athletes taking part in the Doha 2006 Asian Games to provide cross-sectional
norms for the purpose of talent identification for combat sports. The combat sport demonstrating greatest
evidence of physical homogeneity was wushu, while judo had least homogeneity. Decreased homogeneity was attributed to the
extensive range of weight classifications. Sports TrainingThe
sports training theme included presentations on coaching and the coaching
process, talent identification and early development, training, and new
technology in sports. Ye Tian (China Institute of Sport Science, China) gave a keynote on monitoring of sport training and regulation of
competitive state in elite athletes.
Scientific training monitoring is important in
evaluating training workloads, assessing exercise-induced fatigue and
preventing overtraining. Biological indices are used as guides to
training. Monitoring in sports training involves diagnosis of physical functioning,
assessment of psychological
state, and analysis of movement techniques. Regulating elite
athletes’ competitive state can not only enhance athletes’ sporting
competence but also give full play to their acquired maximum sporting
competence in competition. The regulation of competitive capacity by means of
experimental testing is primarily based on regulating physical competitive
capacity, regulating mental competitive state, prevention and treatment of
athletes’ injuries and illnesses, and traditional Chinese medicine. Carla Murgia (Delaware State University, USA) reported the positive effects of dance proprioception conditioning and resistance band training for 10
weeks on joint kinesthesia and injury
prevention in 92 female elite gymnasts aged 13 to 21 years. Paul Fiolkowski (University of East London, UK) also showed the effectiveness of a 6-week balance
training program (a wobble board or T-band kicks, training
three times/week for six weeks) on
lower leg muscle activation and balance for 12 normal subjects. Motor Control
Raymond So (The Hong Kong
Polytechnic University) conducted electromyographic
time-frequency wavelet analysis of
quadriceps muscle during repeated maximal isokinetic knee extension and
flexion exercise performed on a Biodex System for 11 active young males.
He documented the shift of the frequency intensity that relates to the
decline of dynamic muscle power. Luduan Zhang (Cleveland State
University, USA) examined motor command
for activating and relaxing leg muscles from different regions of the brain
in 12 young healthy volunteers. The primary control area generating
the command to initiate voluntary knee extension is in the frontal lobe
near the motor cortices, while that to initiate extension is in the parietal lobe
close to the sensorimotor integration regions. A functional MRI study on 12 subjects by WanXiang
Yao (University of Texas, USA) showed that brain activities during eccentric and concentric muscle contractions
may depend on resistance load at or above 30% of MVC. Qin Lai (Wayne State University, USA) showed that
for 33 subjects, feed-forward control and consequently skill
acquisition on balance can be enhanced if providing augmented feedback simultaneously
with practice as concurrent feedback. Learning a target sinusoid on a
stability platform places high demands on feed-forward control or
anticipation, since subjects have to consistently shift body weight and
overcome body perturbations. John Liu (Springfield College, USA) investigated
the effects of different object speeds and ranges of limb movement on
coincident timing performance of 35 male and 33 female college student
athletes. Coincident
timing performance was affected by range of limb movements,
suggesting that large range of movements could lead to more timing errors and
pose a greater challenge to the performer. Knowledge of results regarding
timing accuracy and direction error was essential to improvement in
coincident timing performance regardless of object speeds. Male performers
appeared to utilize external, augmented feedback for coincident timing
performance more effectively, whereas female performers tended to be more
effective in using, natural, internal movement information for performing the
coincident timing skill. The role of peripheral
awareness in decision making and sport performance was outlined by
Jannie Ferreira (University of Johannesburg, South Africa). In the
study of 30 elite rugby backline players, the higher the decision making rating
(based on coaches ratings of players using a Verusca analyzing system of five
rugby matches) the better the players scored on the central peripheral
awareness test (based on the Wayne Saccadic Fixator score). Liya Lin (Guangdong Provincial Institute of Sports Science,
China) analyzed compressed spectral array electroencephalograms to evaluate the
effects of high-altitude training on adaptation in nine elite swimming athletes from the Guangdong
Swimming Team before competition. After
high-altitude training, the average frequency of brain information
distribution was higher than before high-altitude training. The lack of
oxygen creates changes in brain function to which the body adapts. Practice, Instruction, Expert PerformanceMark
Williams (Liverpool John Moores University, UK) chaired the session that
included Richard Masters (Liverpool John Moores) and Jonathon Maxwell (University
of Hong Kong). What makes the difference between elite and non-elite
athletes? The view that “elite athletes are born” does not appear to hold
true. While the old adage of 10 years and 10,000 hours = elite level
(equating to 20-30 hours per week) still holds some truth, it is not
necessarily coached time and game time that are needed to achieve these
numbers. More evidence around deliberate
play or non-coached play (e.g. street soccer, backyard cricket)
can and should provide an important contribution to performance improvement.
Elite athletes are better at anticipating what is going to happen through
visual cues, recognition of patterns or structures and more accurate search
strategies of the opponent leading to a refined increased in the possible
outcomes and better tactical decisions.
It is not as simple as “talent identification” either. Motivation of
the athlete (both internal and external) would appear to be the most
important factor (probably a strong correlation with deliberate play) in
addition to traditional talent identification factors. Interesting data from European soccer
academies showed that despite the same anthropometric data your chance of
selection into an academy was improved if your birth data fell within the
first three months of the selection year! Our
theoretical understanding of practice and instruction in sport has turned more
towards an implicit
learning model (automatic) as opposed to the more conscious
explicit model, which can be destabilized under competition pressures.
Implicit learning techniques have been evolving in training situations with
the use of dual task learning, but newer strategies include analogy learning
and errorless learning. Errorless learning with under-developed
cognitive resources (e.g., young children who have not programmed their minds
with previous error-ridden experiences) may benefit from this type of
learning. Jonathon Maxwell presented evidence of such a technique by getting
children to start learning golf putting starting close to the hole and then
they got progressively further away from the hole but noticeably trusted
their learnt technique and did not try to change what they were doing. Again,
when under pressure, their success rate did not alter. Perhaps error-less
learning could also be used for the poorly coordinated child who avoids the
task as it is too hard and they learn to fail. Whether error-less learning is
valid in an adult-trained population is not known. Training an athlete revolves around the acquisition
of skills and perhaps it is time that we demand of coaches to use
evidence-based training methods. Talent DevelopmentTricia Leahy (Hong Kong Sports Institute) talked about developing giftedness, where the aim is to pursue excellence in the international arena. “The athlete entourage” concept assumes we need sport-science support for the athlete and coach and uses a bio-psycho-social paradigm. Characteristics of effective scientific support systems should include multidisciplinary teams with practice informed by science, scientist-practitioner strong links, on-field sport science provision, sport-specific expertise and a highly individualized approach. The question to ask is whether the scientific support systems are helping. Tricia then reported some statistics that stunned the audience. Apparently there has been criminal sexual abuse in 15% of the total Australian elite sport members, and of those who had been abused 50% had sustained abuse in sport. Most abuse occurs in an environment of fear and entrapment where the person is confused. As sport has an emotionally intense environment there is a need for a code of ethics and for education about ethical competencies for sport scientists and coaches. Silence about perpetrator abuse needs to stop and bystanders need to report incidents. Parents need to be involved in monitoring behavior but can also be part of the bad environment (e.g., parents shouting from the sideline). Tricia recommended reading the 2005 consensus statement on training the elite child athlete at the IOC's official document site. Sport CultureSigmund
Loland (Oslo Sports Trauma Research Centre, Norway), a sports philosopher,
opened the conference with his keynote presentation entitled Citius, Altius, Fortius? Moral and immoral
interpretations of athletic performance. He presented three models of sports performance and how each
affected the individual and society as a whole. While sports perfectionism was his
ideal (a model in which the rules that govern fair sport are also applied
outside of this realm in society as a whole), he concluded that we live in a
changing environment and others view this model as outdated. Perhaps we will
see the “Olympic ideal” retained while other sports will provide the
entertainment factor with the use of biotechnological and medical
advancements. Health PromotionThe
health promotion theme included presentations on physical activity promotion
and programming, epidemiology of injury and illness, population-based surveillance
and disease prevention and treatment, physical exercise, Tai Chi Chuan and
other Chinese martial arts. Victor Matsudo talked about mobile management
using an ecological
model. Moderate activity is
enough to protect against cardiovascular disease. Accumulated physical activity
works. Interval activity is actually slightly better so the suggestion is to
try 3x 10 minutes brisk walk at least 30 minutes per day and 5 days per
week. The “half hour man” (a clock
cartoon) is used to encourage physical activity. There is also advocacy at the medical level
with pill boxes that are empty but contain physical activity messages on the
outside. The message is that physical
activity is the best medicine. Relative
risk of illness or injury multiplied by peoples’ indignation of the cost or
other effect of the illness of injury is equal to the social perception of
risk. Sufficient social perception of
risk leads to social mobilization–getting
people to want change–which will increase physical activity in the
population. Walter
Fontera (President of the International Sports Medicine Federation,Harvard
University) elegantly presented the phenomenon of sarcopenia (loss of muscle
mass) as a physiological change with age and its contribution to loss of function
In his keynote presentation titled Ageing
– How Can Exercise Help? he stated that the elderly fear losing
independence more than death. Sarcopenia as an entity is not well defined in
the literature, with no specific definitions when compared to other ageing
changes such as osteoporosis. It is
associated with a reduction in physical activity, low body weight, smoking,
and a reduction in Vitamin D and testosterone levels. Cross-sectional studies
in the knee and elbow show a reduction in isokinetic strength of between
15–26% in this population. This loss of muscle mass is not just muscle
atrophy: the amount of intra and inter-muscular adipose deposition (non contractile
tissue) increases with age and there is a reduction in the quality of the
muscle fibers that remain. On a molecular level there is increased synthesis
of serum
myostatin which is a negative regulator of muscle mass resulting
in a decrease in muscle protein concentration per fiber. In addition there is
an increase in glycosylation and oxidation of muscle proteins. Walter Fontera presented information
pertaining to strength or resistance training and suggested that with
standard exercise prescription (2–6 sets per session for each muscle group,
5–15 reps per set, 6–9 s per rep (slow), 40–90% of 1 RM, 2–5 days per week)
that in 12 weeks we are able to replace what has been lost over several
years. But the response rate varies between individuals, with 10–180%
increase in strength from baseline. While there may also be differences in
muscle hypertrophy between individuals, muscle strength and level or
functioning are more important measures. These improvements are due to a
reduction in myostatin levels post exercise and the anti-inflammatory effect
that exercise provides; it also helps if you have a particular allele of the
IGF-1 gene. Walter
believes the way forward is to combine aerobic exercise, resistance training
and flexibility for the elderly, but the challenge is to combine them in such
a way as to maintain adherence. Additional strategies that have been investigated
include diet
(an increase in protein intake is advisable and has been shown to have a
synergistic effect with exercise prescription of between 3–6 hours per week
in the elderly), and hormonal intervention (testosterone, human
growth hormone, insulin-like growth factor, and myostatin inhibitors). There
are only small short-term studies in the literature, and while they show
benefit, either their short-term side effects preclude use (e.g., myostatin
inhibitors) or we do not know the long-term risks. Sports MedicineSavio
Woo (University of Pittsburg, USA) chaired a symposium on tendinopathies
in athletes, featuring orthopaedic surgeons Kai-Ming Chan (Chinese
University of Hong Kong), Chig-Jen Wang and Chih-Hwa Chen (both from Chang
Gung University, Chinese Tapei). The pathogenesis, biochemical and
histological changes at the tendon level with the abnormal healing concept
were outlined. Weak evidence for the use of extra-corporeal shock-wave
therapy in the treatment of plantar fasciitis, calcific rotator cuff
tendinitis, lateral epicondylopathy and patellar tendinopathies was presented
by Chig-Jen. Surgical management for chronic overuse syndromes such as
chronic Achilles over-use injury, chronic patellar tendon over-use injury and
chronic tennis elbow overuse injury were presented by Chih-Hwa, but he did
not add any new information. The
holistic approach to tendinopathies –a Traditional Chinese medicine model–
was an interesting look at East and West presented by Kai-Ming, but he
admitted to no actual hands-on use of such a model! For those involved with Asian athletes,
knowledge of these alternative treatment strategies that patients may be
seeking provided some useful information.
Traditional Chinese medicine involves the synergistic use of herbal
medicines applied orally or topically (to provide
anti-inflammatory action, promote micro-circulation, promote matrix
deposition, and reduce adhesions), acupuncture as a pain relief, manipulative
therapy (tuina) for mechanical stimulation of remodeling and Tai Chi
as a functional exercise regimen incorporating proprioception and restoration
of tendon function. These strategies
are applied simultaneously and not in a step-wise fashion, as each has its
own scientific pathway (not actually presented or known) with clinical
relevance in the holistic management of tendinopathies. Will East and West
ever meet on this issue? Tianjun
Wang presented the effect of Fu’s subcutaneous needling (FSN) for tennis
elbow. Normal-needling acupuncture was
compared with FSN. According to the uncontrolled clinical trial FSN was
quicker and better. With FSN the
needle is put in under the skin but not in the muscle, and is moved for one
minute then left in for 24 hours. The
FSN tube creates tension under the skin.
Patients reported no pain when the needle was in. Only one treatment per week was needed for
FSN compared with acupuncture of three times per week. Tianjun reported that
18 of 48 patients were cured in one week using FSN and overall there were
significant beneficial differences in curing rates with FSN compared to
acupuncture. There was no suggestion
of the mechanism by which FSN would work.
This may be a technique that can reduce pain in athletes, if it is not
all down to the placebo effect of novelty. Sport
related sudden
cardiac death syndrome is a constant reminder to the hazard of
sport and exercise participation. Fabio Pigozzi (University of Rome, Italy)
chaired the athletic heart symposium with speakers Hans Dickhuth (University
of Freiburg, Germany) and Antonio Spataro (University of Rome, Italy). Hans
Dickhuth outlined the morphologic and functional features of the athlete’s
heart. Recognized cardiac
morphological and functional adaptations that are nowadays termed the
athletes heart include most notably an increase in left ventricular end
diastolic cavity dimension and wall thickness, resulting in increased left
ventricular mass. Athlete’s heart is the result of chronic dynamic training
and is not seen in static training (e.g. runners versus weightlifters). These
adaptations will begin to regress as early as three weeks post training with
bed rest. In addition there is no evidence that such adaptive changes
predispose to long-term cardiac damage or abnormalities. An
Italian perspective of cardiac pre-participation screening was
provided by Antonio Spataro and Fabio Pigozzi. While death from cardiac
causes during sports participation is not a new entity, the role of the media
and fan interest serve to highlight such tragic events. This dramatic event
occurs at a rate of one in 100,000–300,000 per annum in athletes under the
age of 35 years, 75% of the time in competition. Etiology varies by
geographical region with hypertrophic obstructive cardiomyopathy and
anomalous coronary artery common in USA (36% and 12% respectively),
arrythmogenic right ventricular dysplasia and anomalous coronary artery
common in Italy (23% and 12% respectively), myocarditis common in Germany and
Marfans syndrome common in China.
Ventricular tachycardia sometimes precedes fatal ventricular
fibrillation, so the early activation of CPR and the use of an automatic
external defibrillator are paramount to survival. Unfortunately survey data
from 2005 showed that success rate with an automatic external defibrillator
with those under 30 years of age is very low. The
Italians presented a more aggressive model (in use since 1971) of compulsory
pre-participation cardiac screening for those involved in competitive sports.
In 2003 it was estimated that 5 million people had undergone
pre-participation cardiac screening annually. Yearly medical history,
physical examination and a 12-lead ECG both at rest and after a three-minute
step test provided them with a 96% negative predictive value and a 90%
reduction in sudden cardiac death over 30 years. But while it served as a useful
reinforcement of a structurally normal heart, the positive predictive value
was low and the false-positive rate was high mainly due to the athletic
cardiac adaptations that occur with training and the changes that these make
to the ECG. While 80% of patients with minor ECG changes (such as non
specific T wave inversion, R and S wave voltage increases and deep Q waves) will
have structurally normal hearts, according to the speaker the rest may
proceed to clinically significant disease and therefore must be followed
routinely for determining risk of sudden cardiac death. This
series of lectures raised more questions than it answered. What is the financial
cost to the public or individual or sporting organization of such an
aggressive regimen with a high false-negative rate? What is the resource accessibility
and availability needed to cope with the demands of ECG interpretation and
ultimately echocardiography referral? Why annual screening? It is a useful
reminder of the purposes of screening and the rules that govern the
usefulness of a test as a screening tool.
Chris Milne, in reviewing our conference report, made the following comment…
“The Italians are in a club of one when it
comes to their recommendations re routine pre-participation ECG screening.
The consensus amongst clinicians is that a lot of the Italians' cardiac
problems are due to a small genetic pool in the communities studied, and
would not be replicated elsewhere. Also, the number of false positive results
generated causes flow-on effects and much human angst.” For an overview on pre-participation screening see Pigozzi et al. (2003). Injury PreventionThe
Norwegian team of Grethe Mykleburst, Lars Engebretson and Tron Krosshaug, all
from the Oslo Sports Trauma Research Centre, delivered an excellent
presentation on injury prevention in sports focusing on the
lower limb. Examples were provided for hamstrings strains, non-contact ACL
injuries and ankle sprains. Their
research and intervention strategies that revolve predominantly around the
sports of handball, soccer and alpine skiing can be viewed on-line at www.ostrc.no or www.skadefri.no; the latter is in Norwegian but be
translated into English in the near future.
Most
studies defining hamstrings strain risks are too small to
make moderate causality associations, but age and previous injury are well
recognized risk factors for this type of injury. Muscle overload in eccentric
contraction with the knee in 20-70º of flexion appears in kinematic studies
as the defining mechanism for hamstring strain. The implementation of a
prevention strategy using the Nordic or Russian Drop Protocol is well known
and has shown a dramatic reduction in hamstring injuries. Nordic
hamstring stretching (3x 30 s) should be included during warm-up
and also competed three times per week for 5-10 minutes each session. The Nordic program should be completed
three times per week pre-season and two times per week in-season. Attention to detail and oversight are the
key factors in improving athlete compliance in this area. Ropes or belts
should be used to control the drop to the point of muscle tightness/pain in
the initial stages to reduce delayed onset muscle soreness that limits such
an activity. The
incidence of non-contact
anterior cruciate ligament (ACL) injuries is much higher in
woman’s sport (soccer, handball, basketball and gymnastics) especially those
in the second decade of life, with a 5:1 gender ratio. ACL injury registry
databases have been set up in the Scandinavian countries over the past four
years for patients undergoing surgical repair for ACL ruptures. The injury
rate across all sports is higher in competition than in training. There are
many other risk factors, which can be divided into external (e.g.,
competition rather than practice, footwear with a higher number of cleats,
surfaces such as artificial versus wooden floors, meteorological conditions
such as lower rainfall) and internal (smaller intercondylar notch width or
smaller ACL, lateral versus medial posterior tibial slope, pre-ovulatory
versus post- ovulatory menstrual cycle phase) but are again based on small
studies and generally only look at one variable at a time. In published
kinematic studies there is agreement that most injuries to the ACL are
sustained in the pivoting or plant foot and cut (60%) and one-legged landing
(30%) with the knee moving into a valgus position within a short time frame
of the foot contacting the surface (within 33 ms) in addition to anterior
tibial translation with the knee in a small range of flexion. Diagnosis
of ACL injuries can be based on extreme acute knee pain post strenuous
activity, inability to carry on activity, a ‘pop’ sensation in the knee,
hemarthrosis, a positive pivot shift test to rule in ACL injury, a negative
Lachman test to rule out ACL injury. An MRI will accurately diagnose ACL
injury in 95% of cases. ACL
injuries are uncommonly associated with other knee ligament injuries: only 1%
have an associated lateral collateral ligament tear while 5% have an
associated medial ligament injury. However, up to 50% have an associated meniscal tear–more
commonly lateral meniscus in the acute situation and medial meniscus in the
chronically ACL deficient knee. No
treatment intervention has been shown to alter the risk of osteoarthritis
development. Patients
can be divided equally between being copers (able to cope with level of
activity), non-copers, and adaptors (adapt level of activity to deal with ACL
deficient knee) but currently we are not able to predict who will fall into
which category. Perhaps those who do not cope have ongoing chondral damage
due to anterior tibial translation or rotational movement. Treatment choices
between surgical and rehabilitation versus rehabilitation alone should be tailored
to the individual. Surgical interventions utilize bone-tendon-bone grafts or
hamstring grafts and newer techniques are using double bundle rather than single
bundle grafts to control rotation and possibly reduce osteoarthritis risk. If
non-surgical rehabilitation alone is the treatment of choice, the patient
should be re-assessed at 3–4 months.
If there is recurrent instability or patient unease then delayed
surgery can be an option. Post operative rehabilitation programs will
vary with surgeons but all should involve early quadriceps activation, range
of motion exercises with the aim for full knee extension, and early
closed-chain kinetic exercises, with quadriceps strengthening and neuromuscular
training to ensure knee joint stability. Implementation
of prevention programs involves neuromuscular and proprioceptive training
regimens to reduce dynamic loading at the tibio-femoral joint. In Norway
prevention programs involve floor, balance and wobble board exercises
with five minutes at each station for a 4–6 week period and then weekly
in-season. Balance prevention programs showed a dramatic reduction in the
number of injuries but discontinuation of the program once again saw the
numbers of non-contact ACL injuries rise. This training should be done at the
beginning of a training session to reduce the impact of fatigue on control.
Ideally it would not be in isolation and as part of the structured team
warm-up (cutting moves concentrating on knee over the second toe concept, two
feet landing and multi-step deceleration methods) with additional wobble
board strategies. Coaches nationwide in Norway are using the injury
prevention program. The importance of general aerobic fitness, strength,
plyometrics and stretching should not be forgotten as components of any
prevention strategy. The speaker
recommended the IOC's current concepts statement on non-contact ACL injuries
in female athletes (Renstrom et al., 2008). High
numbers of ankle
sprain injuries are well documented in sport. The main mechanism of ankle sprain is ankle
inversion and plantar flexion prior to contacting the surface and rolling
into supination. Common causes are players being hit from the medial side
(soccer tackle) or landing on an uneven surface (an opponent’s boot). Risk is
identified as greater for those with a preceding ankle injury. Prevention
includes strategies such as bracing or taping (orthoses) especially in those
with previous ankle injuries, balance board training for 10 minutes five
times per week for 10 weeks after an acute injury and then for 5 minutes
three times per week, and an adequate rehabilitation program post injury
(including continued taping until at least rehabilitation has been completed). Grethe
Myklebust stated that continual promotion of injury prevention programs was
important to maintain the injury reduction.
An example was given from the handball study, where there was a
decrease in injury rates when the intervention was put in, then two years
without the intervention where the rate went up, then re-intervention where
the rate went down again. An
evaluation of the FIFA-11 project was also provided, with data showing that
those teams with greater compliance to the intervention program had a lower
injury rate. Coaches used neck hang
cards with exercises to provide options for the exercises to reduce boredom
for players. Improvements to the
program according to the feedback from coaches included less time needed for
exercises and more exercises with the ball.
The website www.skadefri.co has all the videos that Grethe
used to show the injury mechanisms. Football SymposiumThe
three presenters in the football/soccer symposium were Albert Gollhofer
(University of Freiburg, Germany), Sigmund Loland (Norwegian University of
Sports Sciences), and Hans Hoppeler (Department of Anatomy, University of
Bern, Switzerland). Albert Gollhofer focused on non-contact injuries in
soccer, outlining a large list of intrinsic and extrinsic factors accompanied
with situational factors that contributed to non-contact injury rates. Of
these Boot stud and sprig type were examined and their effects on mechanical
loading of the lower extremities were reported. His studies showed that loading
of the lower extremities can be modified by football boot. In laboratory
testing traditional round sprigs generate higher forces in the knee and ankle
joints at low-moderate loads compared to cleats, predisposing the lower
extremity to risk of injury. The effects of fatigue due to a marked reduction
in active muscle control around the lower extremity joints result in
additional instability. Sigmund
Loland again gave a philosophical look at the game of soccer and cheating:
professional fouls, hidden fouls and play-act diving. He concluded that moral
taxonomy is helpful in the development of a rules system by which
to deal with such offences, but the implementation of rules are dependent on
the referee’s interpretation of the intent of the foul. Does infringement of
the rules and referees wanting more information to be able to make decisions
mean further video referee input into sport? Hans
Hoppeler described performance characteristics in football. Soccer
players (apart from the goalkeeper) cover a total distance of 10–12 km during
a game, of which 20–30% is high intensity running with or without the ball
and is dependent on the position. The
challenge is to achieve the required aerobic capacity without a reduction in
time spent on skills–hence the revival of interval training to improve
VO2max. Hans described the high-intensity training regimen developed by
Halgerd and showed a 0.5% increase in VO2max per session with a 10% overall increase
in VO2max over 11 days. Generally a
four-day rotational cycle repeated three times was effective. Each session consisted
of a warm-up phase, followed by a high-intensity phase for four minutes, then
a recovery phase for three minutes repeated three times for a total of 20
minutes. Days 1 and 3 involved two
training sessions, with Day 2 having only one session and Day 4 being a
recovery day. Not known is the exact
mechanism by which the training adaption occurred, so questions around how
often and how long the training effect lasts remain unanswered. Pre-Olympic Conference 2012The conference prior to the London Olympics will
held be at the
Scottish exhibition and conference centre on the banks of the river Clyde in
Glasgow, Scotland in July 2012. Link for details. Acknowledgements: Patria thanks the Faculty of Health
and Environmental Sciences sabbatical fund of AUT University, and Sport and
Recreation New Zealand for conference funding ReferencesPigozzi F, Spataro A, Fagnani F, Maffulli N (2003). Preparticipation screening for the detection of cardiovascular abnormalities that may cause sudden death in competitive athletes. British Journal of Sports Medicine 37, 4-5 Renstrom P, Ljungqvist A, Arendt E, Beynnon B, Fukubayashi T, Garrett W, Georgoulis T, Hewett TE, Johnson R, Krosshaug T (2008). Non-contact ACL injuries in female athletes: an International Olympic Committee current concepts statement. British Journal of Sports Medicine 42, 394-412 Published Sept 2008. |