“An exercise is something you do a movement is something you feel.”
Was the title of Bill Knowles’ seminar on rehabilitating (reconditioning in his terms) athletes from sports injuries.
The question he asks himself is “what’s in the best interest of the athlete?” This often means pulling the athlete out of the injured body and getting them to recognise their athletic spirit again. All too often in rehab settings, the focus of the treatment is on the injured part, rather than on the person (see previous seminar)
Once you recognise that the entire body is supporting the injured knee then your perspective on getting the athlete back to competition changes.
A few key considerations on rehabilitation
Bill outlined some of his principles that underpin his approach to reconditioning.
Rate of force acceptance (deceleration) vs rate of force development (acceleration). The latter is much talked about and measured, the former is where injuries often occur.
Rehabilitation (medical model) vs reconditioning (performance model)
We are looking to get back to performance so we need to think about this from the onset (I will use the term reconditioning from herein).
“We have to stay professionally stimulated” as improving the journey helps athletes. (It’s hard to stay professionally stimulated if you are handing out photocopied sheets of paper with “3 sets of 10” for each exercise for every person who walks into your clinic).
This then encourages us to think of more athletic ways to train. A good way to start improving the journey is through a movement that is familiar to the athlete. Bill showed a video clip of an athlete very soon post injury, who was walking in water with a knee brace and even did some low level bouncing).
The restoration of athletic normal
We are looking to prepare the athlete for return to play whilst also addressing their injury.
Physical literacy, athletic development and athletic normal are all linked and form part of a “training based prevention”.
Compare that to a medical intervention led prevention strategy with exercises which mean they are “just doing stuff”.
“Training is through movement, not simplistic exercises.”
Our aim is “The ability to move efficiently in an athletic environment with precision style and grace.” We can “start encouraging biological healing through movement.”This exercise has the added benefit of encouraging sleeping which of course is a great healer.
If you just look at things from as sports medicine perspective, you might be satisfied with an injury that is healed. However, “just because you are biologically healed, does not mean you are athletically prepared.”
Bill then quoted Carol Welch: “movement is medicine for creating change in a person’s physical, emotional and mental states”.
Followed by Plato: “Lack of activity destroys the good condition”.
The athlete must not forget what is natural and simple (to them) so this must be incorporated into their reconditioning programme.
A “protection mindset” contributes to complexity. This is unnatural and may add no enhanced healing quality if it compromises movement quality.
Rebuilding the formula one car
Formula one ferrari
Bill used a great analogy when looking at reconditioning. If your Ferrari formula one car is broken into pieces, you can attempt to rebuild it and end up with a red porsche. You have ended up with a fast red car, but it isn’t a formula one car.
You have to know what the athlete looks like at the end. “I’m not interested in restoration of jogging, I’m interested in the restoration of acceleration, deceleration and change of direction.”
Movement is so simple and yet so complex. Many clinicians prescribe exercises and restrict on other movements because they are uncomfortable with movement.
(I know one physio whose end stage acl rehab was chatting to a footballer who was jogging on a treadmill! That was his “return to play” assessment).
Bill is a fine example of the GAIN faculty and attendees who learn from the different people and return to their settings to apply, innovate and develop their knowledge in order to help their athletes.
I also spent an hour discussing ACL reconditioning and using the 4Dpro with athletes over dinner with Bill. This was very enlightening and will help the athletes I work with here in Devon: thanks Bill!
Children who get injured or burntout may be competing at sport too much and have too little opportunity to just play. These words on shoulder operations by Hall of Fame baseball player John Smoltz ring very true.
“I want to encourage the families and parents that are out there to understand that this is not normal to have a surgery at 14 and 15 years old. That you have time, that baseball is not a year-round sport. That you have an opportunity to be athletic and play other sports.
Don’t let the institutions that are out there running before you guaranteeing scholarship dollars and signing bonuses that this is the way. We have such great, dynamic arms in our game that it’s a shame we’re having one and two and three Tommy John (shoulder operation) recipients.
So I want to encourage you, if nothing else, know that your children’s passion and desire to play baseball is something that they can do without a competitive pitch. Every throw a kid makes today is a competitive pitch. They don’t go outside, they don’t have fun, they don’t throw enough – but they’re competing and maxing out too hard, too early, and that’s why we’re having these problems. So please, take care of those great future arms.”
Baseball Hall of Fame induction speech, former Atlanta Brave pitcher John Smoltz
If an adult is present, then the sport is organised. If the kids are left to their own devices they play more, compete with each other and on their own terms.
“Injured young athletes are older, spend more time in organized sports, and specialize too early”
Could this be prevented?
The evidence is quite stark if your child is spending too much time in organised activity rather than free play, if they have specialised in one sport and if they have gone through their growth spurt, then they are more likely to get injured (1).
34% of middle school sports participants get injured each year with an estimated medical bill of $2billion (5).
Talented (or early developing) children get asked to play more sport and therefore have higher injury risk (2).
The cumulative workload increases injury risk e.g. Cricketers who do more than 75 throws a week (3).
Early specialisation in one sport leads to an increase in injury risk (4).
Young athletes participating in more sports hrs/wk than their age and participating in>2 times organized sports:free play are more likely to have a serious overuse injury (1).
Injury risk increases in teenage girls from 12-13 years old and teenage boys from 14-15 years old: at their growth spurts (6).
Injury Prevention is always better than cure
Why wait until your player is injured? I prefer to have healthy athletes available all year round.
A 2 pronged approach is necessary to greatly reduce the risk of your child or player getting injured.
Plan your schedule of training and competing. Include free play time.
Implement a strength/ co-ordination exercise regime and stick to it.
Planning: The best place to start is to look at the next 4 weeks. Use this free 4 weekly planner to help. Put in all the school p.e., games and matches, then club training and matches, plus other activities.
You will probably see a lot of competing and travel, with very few rest days, and little planned physical preparation: running, speed or strength work.
How much free play does your child do? That is “jumpers for goal posts” mucking about with friends in the local park or school playground? None? Then they are at greater risk of injury!
Decisions will have to be made about what is a priority, what is “need to do” rather than “nice to do”. If you are playing more than one age group of a sport, then you should consider dropping the lower one.
Coaches should look at the overall workload that their best players are undergoing: it is unsustainable! Can you afford to lose your best player mid-season?
Strength/co-ordination training: It is the ability to control your own body throughout the match and the season that is the key to avoid getting injured. Your exercise programme has to be specific for young athletes: time spent on crosstrainers, exercise bikes and lying down on a bench is time wasted.
They need to lunge, squat, brace, rotate, push and pull: in combination with braking, landing, jumping and moving from 2 legs to 1 leg, up, down and side to side.
I get athletes to implement daily routines, at first only 5 minutes, then building up from there. This summer I have designed specific warm up routines for team sports players based on the recent research and my experience.
Members of the Athletic Development Clubhave all been given my newly designed protocol cards to help them through the season.
Leg strengthening work
The 11-12 minute warm ups contains all the movements necessary to help reduce the likelihood of injury, as well as improve their sporting performance. If done before every training session and match, the cumulative positive effect will be huge.
Coaches and teachers need to take responsibility
“Quality does not just happen. People who believe so, are people who trust in miracles to make their way through life. Quality excellence is an outcome of preparation and relentless practice. It is surely a given then, that there is time set aside routinely for this.” Frank Dick, Winning Matters.
Resisted running drills
I often hear coaches and teachers bemoan the fact that they are struggling to field a team by December due to injuries. Are they still practicing warm up routines that are ineffective and full of time fillers such as jogging, or encourage incorrect mechanics such as high knees and heel flicks?
Do they have a strength programme that helps improve performance and prevent injury? Or do they just use generic exercises that require little co-ordination and involve a lot of sitting or lying down?
A lot of coaches say they are doing the right thing, but how do they know?
Badminton coach James Elkin, Volleyball coach Denise Austin and the Fencing coaches at the SWFencing Hub have shown a great Growth Mindset by looking at what we are doing with their athletes and then changing their practice.
Injuries are far from things “that just happen“. Chronic pain is abnormal in teenagers, it can be prevented.
I set up theSports Training Systemto help busy parents and teenage athletes fit in physical preparation in a safe, effective and time efficient manner. Join nowand in 4 weeks
Parents, look at how much physical preparation and free play your child is involved in compared to organised camps, travel and competing.
“Female athletes have a 4-6 times higher incidence of ACL injury than do male athletes participating in the same landing and pivoting sports” (1)
Hormonal changes: Hormonal changes during the menstrual cycle can have a direct effect on neuro-muscular performance.
Anatomical differences: Females have a smaller intercondylar notch, therefore a smaller ACL.
AnIncreased Q Angle will influence landing technique negatively.
Slower reaction times: Females have slower and less efficient reaction times due to different neuro-physiology i.e.differences in spinal motor control.
Poor landing mechanics: Reduced leg power will cause an increased reliance on the quadriceps and ligamentous structures at the knee and ankle .An increased Q angle in females has a direct impact on landing mechanics.
Less power: Females have reduced power and muscle development.
“Implementation of practical neuro-muscular warm-up strategies can reduce lower extremity injury incidence in young, amateur female athletes.” (2)
Reducing the risk of ACL injury
This diagram summarises the key factors found in recent research on preventing ACL injuries in female athletes.
Screening: Musculo-skeletal screening can help identify specific problem areas for each individual athlete
Footwear: Wear appropriate and good quality footwear to facilitate good foot/ankle mechanics and help control ground reaction forces.
Conditioning: Functional conditioning work, related to individual screening outcomes and specific to sport requirements. To include stretching, strengthening, plyometrics, review of landing techniques, sports specific drills and balance exercises.
Bill Knowles doesn’t have any magic answers or quick fix exercises. His approach to injury rehabilitation based on good coaching and insisting on excellence in every exercise means injured athletes getting back to competition readiness sooner.
Knowles delivered a quite extensive review of his methods and some research on “Return to competition strategies for the load compromised athlete”. This included video clips of his athletes working and also his ideas on creating the right environment and team for athletes to excel within.
He started out having to work with big groups of people and not much kit, so he had to innovate and adapt right from the beginning.
Planned Performance Reconditioning (PPR) not injury rehabilitation
Knowles started with talking about why he doesn’t use terms like “prehab” or “rehab”. These imply start and end points and a medical based model. The athlete would then walk back on to the pitch, start competition and get reinjured.
Instead, the PPR should be an opportunity to get the athlete better and to ensure that they are stretched, challenged and engaged throughout the process. “Ultimately injury is an opportunity to become a better soccer playing athlete and potentially a better soccer player”.
In high performance sports you should STRIVE for a better soccer player.
In order to evaluate and plan what you are doing you need to combine Evidence Based Medicine (Science) with Experience Based Evidence (Art).
The coaching of the rehab process was emphasised time and again, the athlete and the exercise must be coached well. “Exercise is something you do, movement is something you feel” get the athlete out of the injury and remember who they are”.
A Joint Compromised Athlete is a Load Compromised Athlete
The joint is not to be trained in isolation, it is part of the whole body and the loading has been compromised too.
Once you are a LCA you are always an LCA. That is why you need an “Athlete Sustainability Programme”. This is something that is included throughout the year to prevent lapses.
This is a Performance based model, compared to a Physio or Medical based model: they are not experts in planning performance training.
This was a theme that came up several times over the conference (And Rob Newton mentioned this at the RFU conferencetoo about Australian sport) where teams are now letting physios lead training sessions with “Pilates” or “core” and wondering why they are not performing on the pitch!
“It’s a brain injury dude”
Knowles explained something called “Arthrogenic Muscle Inhibition” (AMI) which is the change of the sensory receptors due to injury. This results in an inability to completely contract a muscle.
This is a bilateral situation: Quadricep activation deficits of 7-26% in the unaffected limb have been measured. After an ACL injury the athlete is more likely to tear the opposite knee, and more likely to get reinjured than the non injured athlete.
The AMI is severe in the short term, plateaus at about 6 months, and slowly declines over the next 18-33 months! So, training the rest of the body is important to prevent that getting weaker too. This must be continued for nearly 3 years!
The brain has to be worked and rehabbed too: so lots of new challenges, games and activities must be included to ensure the athlete is ready to play and compete.
“The knee bone is connected to the head bone”.
The Central Nervous System has been affected, so this must be trained too: “It is not a race to get them back, it is a process to get them better” Gambetta.
Envelope of healing
The upper limit of the envelope is for the elite athlete, but too much work leads to inflammation. Too little work is safer, but it is not causing enough adaptability.
There are no time frames for the rehab procedures, instead criteria based progressions are needed. Function leads to the next stage. For example, biologically running might be right after 8 weeks, but mechanically the loading ability isn’t ready.
The LTAD process gets interrupted by an injury, so other areas need to be worked on during the recovery. Contact sports players need to be “toughened up” to prepare for training, others can develop volume, load or skill ability. It can be a time to “increase the player’s bandwidth” of exercise competency.
There are so many things that can be done to “stop the bleeding of skills and mindset” when injured. Knowles gave great examples of working with golfers and soccer players on using limited skills, or slower actions with severely injured players very early on in the rehab process.
It was great to see how a World Class expert in rehab works, and how he is passionate about coaching athletes. The videos we watched and practical demonstrations we saw and did later really opened my eyes. (Physiotherapist Sarah and I discussed this when doing therebounder exercises).
The “Progression, Variety and Precision” that Ed Thomas talked about were very apparent in Knowles’s work.
One of the good things about GAIN is the interaction between different professions. Everyone was learning from each other and recognising the transfer across areas.
After witnessing the aftermath of the parents’ races at my daughters’ school sports day last week, I decided to review the current Executive Summary of the Management of Acute Soft TissueProtection, Rest, Ice, Compression and Elevation(PRICE) by the Association of Chartered Physiotherapists in Sports and Exercise medicine (ACPSM).
The previous recommendations by the ACPSM were made based on evidence published up to 1996. These current clinical guidelines, which I have summarised below, were produced by a team of volunteers using evidence up to 2010. Each PRICE intervention has been graded as STRONG, WEAK or UNCERTAIN.
PROTECTION AND REST (STRONG)
“Definitely unload soft tissue in acute phases after injury”. WHY?
Minimise internal bleeding
Prevent excessive swelling
Prevent re –injury
The type and duration of the protection /resting phase is not clear and will depend on the specific injury and its severity.
Progressive and mechanical loading plays a vital role in tissue healing. The transition from this protective stage needs to be supervised by a Physiotherapist.
“Definitely apply ice after an acute soft tissue injury.” WHY?
Cooling the tissues…..
Can limit the extent of the soft tissue injury
Provides pain relief
Can facilitate rehabilitation
The guidelines suggest that crushed ice in a bag which is wrapped with a ‘damp barrier’ i.e. damp cloth or tea towel is applied to the area for 5 – 15 minutes every 2 hours.
During sporting events, application of ice for > 10 minutes can have an adverse effect on athletic performance and increase injury risk.
COMPRESSION AND ELEVATION (WEAK)
“Probably use compression/elevation after an acute soft tissue injury”. WHY?
to limit tissue swelling
can reduce pain due to increased tissue pressures
Evidence is poor to support the use of elevation and most of the research is conflicting regarding the use of compression.
The guidelines conclude, “Probably don’t use high levels of compression with simultaneous elevation.”
If compression bandages or external supports are used they must fit well. They can offer some support and give confidence to the injured when returning to normal function.
Always consult with a Physiotherapist or an appropriate medical professional after a significant soft tissue injury.
In response to Tommy’s question about persistent shoulder pain.
If you have shoulder pain, then there are a few things you need to do:
Diagnosis- what is actually wrong with it? Going to the GP and being told to rest and given some anti inflammatories may work in the immediate future, but not necessarily in the long term.
Similarly if you have a serious tear or rupture, then doing any exercise will make it worse- so you need to understand how severe it is first. Book in for a Physiotherapy(based in Willand, Cullompton) appointment to get the correct diagnosis.
Do not participate in sport until you are pain free.
The Rehabilitation process
Start to work on low level movement and control exercises. This includes extended press ups either against the wall or on the floor, shoulder rolls, shrugs, and protraction exercises.
Isometric contractions are also useful in strengthening a specific weak point under control. So for a thrower/ striker/ racquet sport player, that might mean getting into your sport stance close to a wall and then pushing against that wall for 3-5 seconds quite hard. Rest for 10 seconds, then repeat 3-5 times. See how that react the next day and then you can increase that.
If you have chronic shoulder pain, then it may mean you have to do these exercises on a daily basis as a preventative tool. (The same applies to chronic low back pain). Five minutes a day, every day will help stabilise that joint.
From there you can start to add in multi joint exercises that use the shoulder in more functional ways- dips, press ups (lots of variety here), pull ups, dumbbell presses, and throwing lighter implements for short distances.
Remember: Diagnose, move, stabilise, strengthen, function and consistency.
However, this does not apply to healthy athletes- if it ain’t broke- don’t fix it.
Instead try this series of healthy shoulder exercises to keep things working.
Children and adolescents endure many of the same injuries and mechanical dysfunctions as adults. However, in the maturing skeleton there are some specific conditions that are only seen in the young.
Here is an overview of the common conditions, their causes and how to manage them.
Osgood -Schlatters, Sinding-Larsen-Johansson and Severs lesions
These are non-articular types of osteochondrosis or ‘traction apophysitis’. These specific conditions affect the growth plates, where muscle tendons attach to bone.
They are normally seen in the more active and sporty adolescents during or after a growth spurt. Either one or both limbs can be affected. All three of these conditions are self- limiting and in some cases the symptoms can continue for years.
Recovery rates will vary between each child. Investigations such as x-ray and diagnostic ultrasound are not normally indicated to make a diagnosis.
A common cause of anterior knee pain in the young athlete. Pain, swelling and local tenderness will be present at the tibial tuberosity, where the patella tendon attaches below the knee joint. In some cases a boney lump can be seen. Affects boys more than girls.
A less common cause of anterior knee pain in the young athlete. Pain, swelling and local tenderness will be present at the inferior pole of the patella, at the superior end of the patella tendon (at the bottom of the knee cap).
A common cause of heel pain in young athletes. Pain, swelling and local tenderness will be present where the Achilles tendon attaches onto the heel.
What are the causes of Growing Pains?
Growth spurt (during this period bone will lengthen before muscle. This will put increased pressure on tendon attachment during exercise) Increased intensity of training
Adaptation to a new sport, especially those which involve running and jumping.
Reduced muscle length, especially during or after a growth spurt.
Reduced muscle strength.
Poor control / stability at the spine and pelvis.
Poor foot mechanics.
How to manage the condition
Monitor and keep a record of the child’s growth. This can help to adapt training needs specifically .e.g. during a growth spurt an increased emphasis on stretching is required and maybe some reduced activity.
Reassurance to the child that his/her condition is relatively short term and that by continuing with their sport is not doing any harm.
Activity modification (this should be guided by pain levels. There is no evidence to suggest that prolonged and complete rest is beneficial)
Regular stretching of the surrounding muscle groups
Strengthening of the surrounding muscle groups. This should be focused on during periods of reduced symptoms and limited growth.
Spinal and pelvic stability / control work.
Assessment of foot mechanics Maybe a need to change footwear or use of orthotics. Small heel raises or gel cushions can be useful to control the symptoms of severs.
Use of ice locally
Use of massage to surrounding muscles
Seek medical advice regarding use of analgesics and anti-inflammatories.
Growing Pains could be considered a normal part of growing up. A sound training plan and recognition of sudden changes in growth can help guide the young athlete through the problem.
‘A heel cup improves the function of the heel pad in Severs injury : effects on heel pad thickness, peak pressure and pain.’ Perhamre et al. Scandinavian Journal of Medicine and Science. August 2012.vol 22.4.p516.
‘Childhood lower-limb apophyseal syndromes : “what is the egg on my leg?.”’ Stickland. SportEX Medicine. Jan 2011.47.p22.
‘Adolescent anterior knee pain’ Gerbino et al.Operative techniques in Sports Medicine. July 2006.vol 14.3.p203.
Clinical Sports Medicine. Bruckner et Al. Third edition 2006.Mcgraw-Hill Australia Pty Ltd.
A recent article in the New York Times hailed the Nordic Hamstring Exercise as the saviour of all athletes involved in explosive sports. Citing several published papers, the NYT suggests that this single exercise could put an end to the dreaded hamstring injuries.
We take a more in depth look at the implications of the Nordic Hamstring Exercise relating to both injury reduction, and performance.
Prevalence of hamstring injuries
Hamstring injuries are common in sports characterized by maximal sprinting, kicking and sudden accelerations. Studies have shown that hamstring strains account for about 29% of injuries among sprinters, 16–23% of injuries in Australian Rules football and 12– 16% of all injuries in soccer.1
The recent Rugby Football Union (RFU) Injury Audit showed that 92% of all hamstring injuries were running related, and were the most common training injury.
Not only are they very common, hamstring injuries can also cause significant time loss from competition and training. A rate of 5 to 6 hamstring strains per club per season has been observed in English and Australian professional soccer, resulting in an average of 15 to 21 matches missed per club per season.3
With this in mind, training methods to reduce hamstring injuries should be at the forefront of preparation for athletes of these sports.
What causes hamstrings injuries?
In order to be able to reduce the likelihood of injuries, it is first necessary to identify and understand the factors that contribute to hamstring injuries.
“ EMG analyses during sprinting have shown that muscle activity is highest during the late swing phase, when the hamstring muscles work eccentrically to decelerate the forward movement of the leg”. 1
It has been reported that most hamstring strains occur during maximal sprinting, as this is when the forward movement of the leg is at its fastest. The eccentric overload could put strain on the hamstring muscle and lead to injury. This overload is likely to be exacerbated by inadequate muscle strength.
It has also been suggested that hamstrings are susceptible to injury during the rapid change from their eccentric to concentric action, at the start of the downward swing of the leg. At a high intensity, the force exerted whilst changing the direction of the leg may exceed the limits tolerated by the muscle. This suggests that strength imbalance is also a factor in hamstring injuries.3
Among 64 track and field athletes, 24.2% had suffered from hamstring strains in a two year period following assessment of hip and knee flexion and extension. When these subjects were divided into injured and uninjured groups and compared using the various strength measures, the injured group had greater bilateral imbalance e.g. relatively weak hamstrings compared to quadriceps on either side.6
A literature review during the same study also reported how contralateral (side-to-side) strength imbalances could pose a similar risk for injury. A trend for higher injury rates was found in female collegiate athletes who had strength imbalances of 15% or more on either side of the body. (Ebook on strength for females here)
Strength imbalance of the hamstring muscles compared to quadriceps and contralateral imbalances are both major causes of strains.
Whilst strength is one aspect, timing of contractions could be more important. If the hamstrings are working too late in the running pattern, they will be ineffective in slowing the leg down and may therefore get injured.
Is the Nordic Hamstring the cure?
Figure 1.0 The Nordic Hamstring (NH) exercise. The subject attempts to resist a forward-falling motion using his hamstrings to maximize loading in the eccentric phase. The subject should aim to brake the forward fall for as long as possible using their hamstrings.
A program based around the NH exercise (sets of 12, 10 and 8 repetitions) has been shown to increase eccentric hamstring strength in soccer players when performed 3 times a week over a 10 week period.6 Eliminating strength imbalances in athletes with bilateral hamstring asymmetries has been shown to reduce frequency of injury. 4
However, the NH exercise only impacts on eccentric strength of the hamstring during knee extension. (Most studies also test hamstring strength performing knee flexion/extension, using a dynamometer in a seated position).
However, the concept of “eccentric- concentric” action is an oversimplistic view. The hamstrings actually act isometrically at top end sprinting, with the elastic properties of the tendons being used to transfer energy.
When running, the knee angle does not change dramatically, meaning the length of the hamstring muscle stays relatively fixed. Instead, the biarticular hamstrings (particularly the tendons) work eccentrically to decelerate the leg during the forward swing. Therefore NH does not replicate the actions of the hamstring muscle during running.
“Functional training of the hamstrings should therefore not be done through eccentric training, but in an elastic-isometric way, reflecting hamstring functioning during sprinting.”
So does NH prevent hamstring injuries?
In One study, Soccer Players performed a conditioning program for 9 months, after which, the individuals with a previous imbalance had reduced frequency of injury, similar to individuals with no initial imbalance. 4 Furthermore, the players with untreated strength imbalances were found to be 4 to 5 times more likely to sustain a hamstring injury when compared with the normal group.
Despite the apparent success of the above study, the details of the conditioning program undertaken were not given. This could mean that a number of possible exercises, or combinations of exercises were used, making conclusions about the NH impossible.
Further studies however have described how a conditioning programme of NH is effective in reducing prevalence of both new and recurring hamstring injuries. 1, 2, 8, 9
The results of these studies are positive for athletes and coaches involved in sports involving maximal sprinting as the use of the NH could potentially be effective in reducing injuries.
So is the Nordic Hamstring all that?
Despite the positive findings of these studies, there are limitations with this research that should be considered.
Lack of randomised trials within some studies
Inconsistencies with frequency of injury monitoring(In one study 1, control group were monitored daily, whereas intervention group only monitored at matches, making it possible that injuries could go unrecorded)
Inconsistencies with thoroughness of injury measurement(some groups used MRI and ultrasound to detect/confirm injuries, others only used judgment of physical therapist.)
Possible confirmation bias(therapists expecting less injuries in intervention groups or vice versa could potentially downplay severity of injuries, skewing results)
No studies compare other possible eccentric exercises, so could be a case of “better than nothing”.
One important note of these studies 1,2 is the timing of the interventions. In Both cases, NH was used as part of a pre-season strengthening intervention, meaning an absence of high intensity and volume of matches. Many experienced coaches such as Vern Gambetta have reported an increase in hamstring injuries when the volume of hamstring loading is high, caused by excessive fatigue. Although the participants in the studies may have continued the NH during the season 1, it was only once a week, allowing the hamstrings time to recover.
One major downfall of the NH is that the hip remains in a fixed position while the hamstrings contract. By working with the hip in a fixed position, the exercises fail to replicate the movement patterns that occur during running. The Hamstrings are biarticular, passing over both the hip and knee joints, and during running they play an active role in hip extension as well as knee flexion.
“Therefore the effects of the Nordic hamstring exercise on running performance can be questioned, despite the possible effects on injury prevention.” 10
What should I do to protect my hamstrings from injury?
Strength training is mode specific meaning that the body will adapt to the specific stimulus placed upon it.
It could therefore be suggested that to strengthen the hamstrings effectively to reduce injury and also maximise sprinting ability, exercises should be eccentric in nature but also replicate the movement patterns of running.1,5
(The Run Faster ebook combines specific resistance training exercises and run drills that follow this protocol. It has proven very effective).
Exercises such as Good Mornings/Stiff Leg Deadlifts strengthen the hamstrings eccentrically whilst involving flexion of the hips and would therefore more closely match the specific physiological demands of running than the NH.
Concentric style hamstring exercises such as machine curls are another common method of conditioning.1 However, concentric exercise tends to reduce sarcomere numbers in muscle fibres and consequently results in muscle operating optimally at shorter lengths.3
This training effect raises the susceptibility of the muscle to damage from eccentric exercise. It should therefore be recommended that concentric style conditioning exercises for the hamstrings should be avoided in sports characterised by maximal sprinting efforts.
Other Measures to prevent injury
There are also measures which athletes can take during competition to reduce the chances of hamstring injuries. Hamstring strength has been found to deteriorate throughout the duration of a soccer game, and this fatiguing effect was consistent with a higher injury risk during sprinting movements. 5
Interestingly it was also found that the halftime interval produced a negative influence on eccentric hamstring strength. After remaining seated, strength was lower after half time than at the end of the first half.
This suggests that performing a ‘re-warm up’ after half time may be beneficial, especially with the high injury rates found in the early stages of the second half.
Take Home Message
The high prevalence of hamstring injuries in sports involving maximal sprinting and acceleration shows the importance of an effective conditioning programme for the hamstrings.
Experience of many practitioners suggests that too much eccentric loading before maximal intensity sprinting can lead to injury. Therefore high volume/intensity strength work should be completed outside of competition, with more low volume specific work being done in season.
All found in our Run Faster ebook (click on image)
1) Arnason, A., Andersen, T.E., Holme, I., Engebretsen, L. & Bahr, R. (2008) Prevention of hamstring strains in elite soccer: an intervention study Scandanavian Journal of Medicine and Science in Sports, 18 (1), 40-48.
2) Askling, C., Karlsson, J. & Thorstensson, A. (2003) Hamstring injury occurrence in elite soccer players after preseason strength training with eccentric overload Scandanavian Journal of Medicine and Science inSports, 13, 244-250.
3) Brocket, C.L., Morgan, D.L. & Proske, U. (2004) Predicting hamstring strain injury in elite athletes Medicine and Science in Sports Exercise, 36 (3), 379–387.
4) Croisier, J.L., Ganteaume, S., Binet, J., Genty, M. & Ferret, J.M (2008) Strength imbalances and prevention of hamstring injury in professional soccer players: A prospective study American Journal of Sports Medicine, 36, 1469-1475.
5) Greig, M. & Siegler, J.C. (2009) Soccer-specific fatigue and eccentric hamstrings muscle strength Journal of Athletic Training, 44 (2), 180-184.
6) Mjolsnes, R., Arnason, A., Osthagen, T., Raastad, T., & Bahr, R. (2004) A 10-week randomized trial comparing eccentric vs. concentric hamstring strength training in well-trained soccer players Scandanavian Journal of Medicine and Science in Sports, 14, 311-317.
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Many athletes and recreational sports people suffer from on-going knee pain and soreness. Today Physiotherapist Sarah Marshall looks in more detail at one aspect.
One of the most common types is Anterior Knee Pain (AKP). It describes pain at the front of the knee and can affect up to 40% of the population. It is especially common amongst athletes, yet not disrupt their sporting function or ability.
What are the causes of AKP?
There are many causes of AKP and I have listed the most common below. Symptoms will often present without specific injury. Any persistent pain must be assessed by an appropriate medical professional in order to make an accurate diagnosis who will then advise on the correct treatment plan.
Patello-Femoral Joint Pain (PFJP) is by far the most common cause of AKP. Athletes will describe pain in and around the patella. I would not expect to see any significant swelling around the knee joint.
Symptoms are usually aggravated by stairs, kneeling, squatting, lunging and running. PFJP can also cause pain at rest, especially when sitting for long periods (movie goer’s knee).
A Patella Tendonopathy, Fat Pad Irritation / Impingement, Bursitis and Patella Instability with also produce AKP.
What causes PFJP
There are many contributing factors to the development of PFJP
Local muscle weakness (especially quadriceps)
Poor neuromuscular control
Muscle tightness (especially quadriceps and hamstrings)
Poor hip / pelvic control / stability
Poor foot posture / mechanics
All of the above will increase the functional loading of the Patello-Femoral Joint which is likely to cause inflammation and pain with repeated use. PFJP is also a very common complaint following any knee joint surgery and must not be missed as referred pain from an old Posterior Cruciate Ligament injury.
Management of PFJP
Always seek professional adviceif you can before embarking on a rehabilitation programme. Initially, pain levels need to be managed and controlled before early rehabilitation can be progressed.
Activity modification i.e. avoid aggravating factors
Soft tissue massage
Stretching programme (hamstrings, quadriceps, gastrocnemius, anterior hip structures)
A graded strengthening programme with initial emphasis on quadriceps
Hip and pelvis stability exercises ( transversus abdominus, gluteus medius)
(Post rehab, there are 3 keys to maintaining Knee Health)
There are limited surgical options for this problem with relatively poor outcomes.
A biomechanical assessment of the foot can help determine whether shoes orthotics are indicated. Commitment to rehabilitation must be adhered to for many months in order to achieve individual goals.
Unfortunately, without the appropriate management, PFJP often develops into a chronic problem.
If you want an individual assessment on your knee pain, then please book in to see me.