Outcome measures: An observation and a reflection

Sports science and strength & conditioning practice is built on a foundation of identifying a problem, testing the problem, applying an intervention and then re-testing to ensure progression. Athletes will buy into fitness testing, injury prevention and subsequent high performance behaviours if they are given the impression that their coach and medical team know what they are doing and things are done with a purpose (Kristiansen and Larsson, 2017). This begs the question whether coaches can justify and clinically reason their battery of performance tests.

When applying a performance measure, understanding of the underlying kinematics is essential to understand the validity of the test to the desired outcome. The OptoJumptm is a valid tool in assessing a reactive strength via  drop jump (Healy et al., 2016) however what components of the jump is the coach wishing to address? The validity of the tool is the not the same as the validity of the test. For example, reactive strength index (RSI) can be influenced by a reduced contact time (stretch shortening cycle via the musculotendinous unit) or via total jump height (power output throughout the lower limb and nervous system) or a combination of both (Healy et al., 2017). Understanding these mechanisms may influence the instructional bias of technique given by the coach in order to test what is desired.

With complexities over a test like an RSI to something seemingly obvious like a jump, testing for broader components of fitness and multiple movement patterns is much more difficult.

The Yo-Yo intermittent recovery test (IRT) is reported to be a valid measure of fitness and correlates to match performance in football (Krustrup et al., 2003). However, this is an example of a fitness capacity test and in fact correlates to fitness capacity in a match scenario. In field based team sports, there are a large number of variables and complex interactions that all contribute towards “performance” as an outcome (Currell and Jeukendrup, 2008). Krustrup’s conclusion was based on correlated Yo-Yo IRT results to high speed running in a game (>15km.h-1) with a strong correlation (r=0.58). Overlooking the methodological accuracy of this (pre-GPS, using VHS locomotive assessment retrospectively), the correlation is between two differing metrics. Where the high speed running was recorded over 90 minutes of varying intensities and periods of effort (12 players across 18 different games), the Yo-Yo IRT covered 1.7km in a mean time of 14.7mins with incremental increases in pace dictated externally. For a test to be considered a valid indicator of performance, it should meet the same metabolic demands as the sporting activity (Currell and Jeukendrup, 2008). The Krustrup paper does not make this comparison, instead analysing physiological markers from rest to exhaustion during the Yo-Yo IRT, not exhaustion markers in comparison to game data.

Perhaps semantics, but in fact there should be differential terminology to distinguish “fitness performance” from “athletic” or “sporting performance.” It should be considered that sporting performance is influenced by a large number of uncontrollable and non-modifiable factors that would make any comparison of validity and reliability to outcome measures unfair. Essentially, recreating a competitive environment is near impossible. This raises the question whether we are exercising just to improve test scores or, closing the loop and relating exercises to performance? Does raising the envelope of one, consequently improve the other? Something that we should not only be asking ourselves, but a question we could come to expect from coaches and athletes a like.

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Does the research answer this?

It has been suggested that stronger athletes produce faster sprint time, quicker change of direction speeds and higher vertical jump scores when compared to weaker athletes of the same sport (Thomas et al., 2016). Squat jump (r = -0.70 to -0.71) and counter movement jump (r = -0.60 to -0.71) demonstrate strong correlations to change of direction speed (Thomas et al., 2016). Peak force during isometric mid thigh pull was significantly correlated to 5m sprint time (p <0.05) however this correlation was only moderate (r = -0.49). But again, does this correlation transfer into performance if the testing protocol doesn’t accurately mirror sporting performance?

Sprint times over 40m have been shown to decrease following an acute bout of heavy loaded squats, hypothesised to be due to post activation potentiation (Mcbride et al., 2005). Higher squat strength scores also correlate with sprint times over 0-30m (r= 0.94, p=0.001) and jump height (r = 0.78, p=0.02) (Wisløff et al., 2004). Importantly, we know sprint performance tests have demonstrated construct validity to the physiological requirements of a competitive field based game (soccer) (Rampinini et al., 2007), which is ultimately what we are aiming to do; relating performance testing to physiological and metabolic markers from a given sport.

The addition of a jump squat exercise into a training program may help improve 1RM squat and 1RM power cleans (Hoffman et al., 2005). So perhaps yes, there is a perpetuating loop between exercise, tests and performance but the link between them all may not be tangible or direct.

But how do we translate all of these statistics and data sets this to a non-scientific population, as a lot of our athletes are? I’ve developed the following analogy to try and help with this.

 

Solar system analogy:

If we consider that “athletic performance” is the main focus of any intervention, much like the sun at the centre of the solar system. This is the bright light that everything revolves around; media, finance, fan base and support and so on. It could be argued that any intervention we have as coaches will never truly replicate “athletic performance” but should be influenced by it. This influence works both ways, positively and negatively. For example, if we maximally test an athlete before a competition, this will likely have a negative impact on “athletic performance”. Conversely, if we were able to collect data that informed a training program to improve athletic performance, despite not actually replicating “athletic performance” it would (hopefully) have a positive impact. For example, a football game is determined by so many uncontrollable variables that can not be replicated in a gym, but we might identify that a player needs to improve their 5m sprint time which in turn, will benefit performance.

Figure 1 solar system
Figure 1: An analogy depicting the relationship between “athletic performance” and controlled interventions / measures. The skill of the coach is identifying which outcome measure or intervention is going to have the greatest influence on athletic performance.

Let’s consider our potential interventions to be orbiting the sun (Figure 1). There is an interaction between the planets and the sun via gravity but they do not have a direct overlap, where the planets do not collide with the sun just as an outcome measure does not truly match sporting performance. We know that larger planets have a greater influence, so as coaches, we are trying to affect the level of positive interaction with “athletic performance”, the gravitational interaction. By influencing links between exercise intervention and outcome measures, we can affect the size of these planets. In turn, this will have a greater interaction with the centre of our solar system, “athletic performance” (Figure 2). Much like the universe, there will be many different solar systems just as there are different sporting codes and contexts, so the skill lies in identifying the most influential planets in your solar system.

figure 2 solar system
Figure 2: The impact of enhancing an intervention or measure on sporting performance, in this case there has been a greater focus and development of the blue “planet” which has changed the interaction with the “athletic performance”

 

A clinical reflection:

For long term injuries, I utilise a continuum to guide return to play (train / play / perform), often these stages are guided by outcome measures linked to goals and aims for stages of rehab. Typically these tests are scheduled in advanced and often follow a planned “de-loading” micro-cycle. This helps with continuity and, as much as you can in sport, standardisation of the test.

A recent case study found me questioning my judgement and to a degree, wondering if my intrigue and curiosity about my rehab plan drove me to test out of sync with the schedule, instead of doing the test for the athletes benefit.

Following a good period of return to train, the proposed testing date previously scheduled clashed with a squad training session. Observational assessment suggested the athlete was coping well with the demands of training and it seemed counter-intuitive to pull them out of training to undertake some tests. A few weeks later, a gap in the daily schedule presented an opportunity to re-test. The test scores were down compared to the previous month, most likely because the athlete had trained in the morning and trained the 4 out of the last 5 days in some capacity. In previous tests, the athlete had come off of a de-load week and tested the day after a day off.

The result:

The athlete began to question their ability and availability to train. They were visibly knocked in their confidence given a drop in scores, despite me being able to rationalise why this could be. Having had the opportunity to feed my own interest and try to prove to myself that a rehab program had worked, the outcome was much worse. I threatened the confidence of a long term injury returning to training, potentially adding doubt and hesitation to their game and I did not get the results I was expecting.

On reflection, given their time out through the season so far, I should have stuck to protocol and tested on the scheduled day (one training session was not going to increase their chances of availability).. or, not tested at all. Instead, i shoe-horned some testing into an already busy schedule. What did I expect given the current level of fatigue?!

Image result for reflection

Previous results had reached a satisfactory level to return to train and I was now chasing the final few percentages available. To give them confidence? Probably not, as they were training and enjoying the return to train. So perhaps it was just to give myself confidence. An interesting lesson learnt, mostly about myself.

 

Yours in sport,

Sam

Compex doesn’t have to be complex

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I should probably start by acknowledging that there are other muscle stimulation devices available… but I’m not employed by Compex, I just have some very good experiences using their product. This blog was borne out of frustration of seeing Compex machines gathering dust in treatment rooms or being used ineffectively as passive, plinth based modalities. I think a lot of people are missing the trick, you need movement!

While I am an advocate of its use clinically, I  want to disclose that using a Compex will not make a bad exercise good. It is a bolt-on to a rehab program and is something that can make a good exercise great. That is key. The clinical reasoning, exercise selection and placement of the stimulation all underpins an effective application, so before rolling it out to all athletes or patients make sure you can reason why it has a place in your practice.

Its all about progress

Like with any intervention, the clinical reasoning behind the application of muscle stimulation can influence its use at different stages of injury and rehabilitation. In the acute stages, it is believed that muscle stimulation may modulate pain. For an interesting read on the use of electricity and pain throughout the centuries, click here. However, as we understand more about optimal loading and mechanotherapy, we probably need to limit the time an athlete sits on the plinth watching the latest Mannequin Challenge on their smart phone while their quad twitches. It is worth considering that a Compex placed on a dead body would still cause it to twitch. The key is to get them moving and use the Compex to either facilitate movement or provide an external load. Interesting that we can use the same machine and the same settings to either regress or progress an exercise… the key is in the exercise selection.

Consider the tissues

Muscle injury: It should be pretty obvious that placing a muscle stimulation device, designed to promote contraction of muscle, on a contractile tissue with a tear or micro-damage could have negative consequences. For a second, lets forget the Compex. Respect the pathology and consider if you really need to lengthen or contract that muscle to load it. Is there a way you can work that tissue as a synergist perhaps? If the hamstring was injured in the sagital plane, can we move through coronal (frontal) planes and still load the hamstring? This could possibly be a slight progression on an isometric exercise and shouldn’t change the length of the muscle that may cause pain or further damage. Certainly more beneficial than sitting on the treatment bed though. So now consider how muscle stim may benefit this stage of injury. It could possibly help with any inhibition due to swelling or pain, perhaps be used to add an increased load to unaffected tissues that you may not be able to load otherwise.

As the healing progresses and the level of activity increases, it is quite common that we see some deficits in muscle function, especially after a long acute phase (if that isn’t a paradox?! Think post surgery or fixation). A good example is post ankle reconstruction, where you have worked on regaining plantar / dorsi flexion but when you ask the athlete to do a heel raise, it’s quite an effort. It may be appropriate to use the Compex here as a little crutch to facilitate movement and contraction. But the key thing here is it is not our cadaver that we causing a contraction in, the athlete is consciously initiating the movement. (Previous blog on internal and external cues here).

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Now promise me if the Compex hurts, you will turn it down. OK?
Progressions by all definition, progress. So after working through isometric and concentric exercises, the program may require some eccentric load. This is worth trying yourself before asking a patient to do it, because a very simple exercise like a TRX squat that may have been cleared earlier in the program can dramatically increase in work with the addition of Compex. Consider a quad injury. The Compex has two phases of a cycle, a fasciculation phase that causes visible twitch and a long contraction phase (depending on the setting, the length and intensity of the contraction change). After one or two cycles for familiarisation, instruct the athlete to work against the contraction – so when the Compex wants to promote knee extension via a quad contraction, sit back and encourage knee flexion. Try this yourself for 6-8 reps and feel the fatigue induced, it usually surprises people. Again, make sure you can reason WHY you are doing this. This is usually a good bridge for someone who needs to step up their program but maybe can’t tolerate external load (confounding injuries, instability of joints, lack of technique etc etc.)

Joint Injuries: In comparison to a muscle injury, your application of Compex may be more aggressive. Because you are unlikely to affect a non-contractile tissue with the stimulation, you may use the eccentric reasoning to help reduce atrophy rates following a intracapsular injury like an ACL. Ensure you know the available range first of course.

With these injuries, the external stimulation may help with inhibition, improve proprioception lost by the ligament or capsule or it may provide stability to the joint by increasing the available contraction. Again, there will be a time and a place and it requires the clinician to reason through the application, but this may be a great addition to a program that is becoming stale.

Tendon injuries: The use of the Compex to enhance an isometric contraction or to create an eccentric contraction may be a great addition for an in-season tendinopathy as a way of managing load. The timed contraction allows clinicians to monitor Time Under Tension (TUT) which is essential for tendon management. If considering a High-Medium-Low frequency through the week, a pain free exercise that is used on a Medium day can become a High load exercise with the addition of an externally generated contraction. But consider the two things that aggravate a tendon, compression and shear. Appropriate exercise selection and range is going to be crucial, that being said, it may be that the addition of stimulation to the quads actually reduces shear through the patella tendon by changing the fulcrum of the patella (no research to back this up, just my musings).

musing
I really like Geckos. I found this Gecko a musing
Conclusion:

I think there are many options out there to enhance rehabilitation by considering the diversity of muscle stimulation. But I want to repeat for the hundredth time, it is the exercise selection that is key. The addition of a Compex will only amplify that choice.  For the patient, it adds a bit of variety to a rehabilitation program and for the clinician it is another tool to help with optimal loading of a healing tissue or structure. I am a big fan of weight training (don’t let my chicken legs fool you) but there are injuries or athletes that for one reason or another are unable to tolerate weights. This is one tool in a very large and overused metaphorical tool-box that may bridge that gap between body weight exercises and weighted exercises. I also believe there is great benefit when complimenting this with Blood-Flow Restriction Exercise or Occlusion training… but that’s another blog.

As always, thoughts and opinions are welcome.

 

Yours in sport,

Sam

Rehabbing teenagers can be awkward! – sensorimotor function during adolescence

There is a bit of a buzz phrase in rehab about “individualising programs” and while it is something we wholeheartedly agree with, it is a phrase that is very easy to say and yet very difficult to implement. Especially when you work with a population where said individual changes rapidly through time, like a teenager! It is a common sight on a training pitch to see a star player in their age group suddenly tripping over cones or developing a heavy touch where there was previously effortless control. Side effects of the adolescent growth spurt, where the brain is now controlling a much longer lever. It’s like giving a champion gardener a new set of garden sheers when for the past year they have used little hand-held scissors and asking to them maintain their award-winning standards. (My garden embarrassingly needs some attention and it’s affecting my analogies).

Master-Gardener-Pruner-Secateurs-Shears-Garden-Hand-plants-Shears-trim-cutter-easy-carry-Garden-Tool
The control and precision between these two instruments is influenced by the lever length of the handles…
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…Similar to a rapidly growing femur and tibia which is still being operated by muscles that have length and strength suitable for shorter levers.

 

 

 

 

 

 

 

 

Alongside the performance related issues, there is suggestion that this period of growth may coincide with increased risk of injury (Caine et al 2008). We believe that bone grows quicker than soft tissue, so we are asking a neuromuscular system to control a new, longer lever using prior proprioceptive wiring. Imagine our gardener again, for a long time he has been able to keep his pair of scissors close and controlled, now with his extra long shears the load is further away from his body, his back and shoulders are starting to ache. Not sure what I mean? With one hand hold a pencil to the tip of your nose. Now, with one hand hold a broom handle to your nose. The longer lever is harder to control. **I promise it gets a bit more sciencey than gardening and broom handles. **

Managing these growth spurts is something we have talked about before and recently contributed to a BJSM podcast on the topic (Part 1 & Part 2) and a complimentary BJSM blog about “biobanding” during periods of growth and development (here). This particular blog was inspired by a recent (2015) systematic review looking into exactly which sensorimotor mechanisms are mature or immature at the time of adolescence by Catherine Quatman-Yates and colleagues over in Cincinnati (here). The following is a combination of their summary and our examples of how these findings can influence our rehab programs.

Tailoring the program:

We have so many options for exercise programs, that’s what makes the task of designing them so fun. It challenges our creativity. When working with a teenager with sensorimotor function deficits, let’s call them “Motor Morons” for short, we don’t have to totally re-think our exercise list, just perhaps the way we deliver them. We previously spoke about motor control and motor learning (here) and how our instructions can progress just as our exercises do, but the following relates to children and adolescents in particular.

Consider the stimuli.

Children aged between 14-16 have well-developed visual perception of static objects however their perception of moving objects and visual cues for postural control continue to mature through adolescence. When very young children learn new skills such as standing and walking, they become heavily reliant on visual cues. Quatman-Yates et al suggest that puberty and growth spurts (think gardener with new shears) brings new postural challenges that causes adolescents to regress proprioceptive feedback and increase reliance on visual cues again. From a rehab perspective, we need to consider this as part of our balance and proprioception program. How many of us default to a single leg stand and throwing a tennis ball back & forth from therapist to athlete? For our Motor Moron, this may not be an optimal form of treatment in early stages, where it is commonly used, however it may incredibly beneficial to that athlete in the later stages or as part of ongoing rehab as we try to develop that dynamic perception.

Consider the amount of stimuli involved in an exercise versus what your goal of that exercise is

We should also consider the amount of stimuli we add to an exercise. Postural stability in children is believed to be affected by multiple sensory cues. If we consider that children are more dependent on visual cues than adults are, perhaps our delivery of external stimuli should be tailored also. With a multi directional running drill for example, there is sometimes an element where the athlete is given a decision making task (a red cone in one direction and a yellow cone in another) and they have to react quickly to instructions from the therapist or coach. Rather than shouting instructions like “red cone”, “yellow cone” etc, hold up the coloured cone for the corresponding drill. This way we are utilising this developed visual perception, minimising the number of stimuli and also encouraging the athlete to get their head up and look around rather than looking at their feet.

When to include unilateral exercises:

Within adult populations, it is often considered gold standard to make exercises unilateral as soon as tolerable. If they can deep squat pain free and fully weight bear through the affected side, progress them to pistol squats ASAP, or single leg knee drives. However, young children (pre-pubescent) may struggle with this for a couple of reasons.

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Difficult enough even for an adult to perform, but uncoupling the actions of the each leg & fine muscle movements to maintain balance are extra challenging for children

Firstly, we need to consider postural adjustments. Where as adults and young adults can adjust their balance with smooth control and multiple, small oscillations, children rely on larger ballistic adjustments. There is also reduced anterior-posterior control in younger athletes which suggests reduced intrinsic ankle control. Put this alongside immature structures and (if working a physio, most probably) an injury then single leg exercise become a progression that may be further down the line than an adult counterpart with the same injury. Instead, consider semi-stable exercises. Support the contralateral leg with a football or a bosu ball – something that is difficult to fixate through but provides enough stability to support the standing leg.

Secondly, we understand that coupled movements are mastered earlier in adolescence, around 12-15 years old but uncoupled movement patterns take longer to develop, 15-18 years old (Largo et al). A good example is watching a young child reach for a full cup of water at the dinner table. It is much easier and more natural for them to reach with both hands than it is with one, as coupled movements are unintended. Rarely do you see a child taking a drink with one hand filling their fork with the other – yet this is something commonly seen with adults as they are able to uncouple and segmentalise. Another example is watching a child dynamically turn, watch how the head, trunk and limbs all turn as a “block”, it is not until further down the line where dynamic movements become more fluid. The argument here is that surely running is an uncoupled movement? Or kicking a football, swinging a tennis racket, pirouetting in ballet – they are all uncoupled, segmental movement patterns that we expect kids to do, and in all they cope with. Correct, but it is usually in rehab programs for kids that we begin to introduce unfamiliar tasks and exercises that they may not have encountered before. Also, we should respect the impact of the injury on proprioception and control. So these are all considerations for starting points in exercise & if a regression is ever required.

For this reason, it is important that exercises are monitored and reviewed regularly. There is no need to hold an athlete back because of their age and making assumptions on motor function because of their age. If they can cope, then progress them. But be mindful of “over-control” where speed and variability of movement are sacrificed in place of accuracy and control (Quatman-Yates et al 2015).

Become a Motor Moron hunter

It is worth spending some time watching training, watching warm ups, watching gym sessions and talking with coaches and S&C’s trying to identify a Motor Moron as soon as possible. It’s important to minimise the chances of an immature sensorimotor mechanism ever meeting a growth spurt. It is when these two things combine that we see kids doing immaculate Mr Bean impressions and therefore increase their risk of injury.Safari-kids

Regularly re-assess your exercise programs. If things arent quite progressing as quickly as they should, it may not be failed healing of an injury, but it may be that we are providing the sensorimotor mechanism with too much information!

 

Yours in sport,

Sam

 

“The Young Athlete” conference 9-10th Oct, Brighton. Here

Hamstring Injury – What are we missing? by Jonny King

We are delighted to introduce a guest blog from Jonny King (@Jonny_King_PT), a sports physiotherapist based at Aspetar, Qatar. Jonny has experience working in professional football in the UK with both Norwich City FC and AFC Bournemouth before he made the big move East to Doha. A prevalent voice on twitter and definetely worth a follow, he provkes some intriguing questions regarding our current understanding of hamstring injuries. We hope you enjoy… P&P

 

Hamstring strain injury (HSI) continues to present as a huge challenge for those of us working within the sport and exercise medicine field – whether that be in a research or clinical setting. Disappointing figures have recently shown that despite an increasing body of publications over recent years and a perceived improvement in understanding of underlying causes, the epidemiology for HSI in elite sport has not changed over the past 10 years (Ekstrand, Hagglund & Walden, 2009) A worrying reality.

Some will argue that WE HAVE improved our understanding and management of hamstring injuries but the evidence base is not being applied effectively into clinical practice. (Bahr, Thornborg, EKstrand, 2015). Others will state that our ability to influence epidemiological data at elite level, has been affected by the evolution of sporting competition including increased physical application. Take professional football for example, both sprint distance (35%) and high intensity running distance (30%) have significantly increased over the past 7 years, alongside a reduction in recovery times as a result of increased fixture congestion (Barnes et al, 2014) These can all be seen as restraints to our drive for better data around HSI.

These are all factors we should appreciate, however are we missing something else?

In brief, we know those at highest risk are those with history of previous strain, weak eccentric strength and those in a fatigued state (Opar, Williams and Shield, 2012). Flexibility, neuromuscular inhibition, biomechanics and H:Q ratios have all been flirted with, but with no real hard conclusion as to their influence on HSI. Identifying those at risk is relatively straight forward these days, given increased accessibility to advanced monitoring technology, helping to identify fatigue or strength reduction. We can thank systems such as GPS and The Nordboard for this. These are for sure all very important considerations as we take a multifactorial approach to injury management and prevention. But, Is there anything else we need to consider?

One area that I feel needs further investigation with regards to HSI is the psychological harmony of the athlete. It may be difficult to account for the primary injury, but are negative beliefs, anxiety and apprehension contributing factors to high rates of re-injury?

jonny blog
More brain training before RTP?

Cognitive functioning and therapy has been discussed at length in the treatment and management of many other musculoskeletal conditions, notably chronic LBP (O’Sullivan 2012) and ACL Reconstruction , with methods such as CBT proving an effective intervention in many cases. I wonder therefore if this needs more consideration when it comes to hamstring injury treatment? Poor psychological readiness has been associated with hamstring strain re-injury (Glazer, 2009) and this would also provide a feasible explanation as to why completion of Carl Askling’s H-Test appears a strong indicator for RTP. Maybe it’s something we are missing, or not considering enough? By more thorough monitoring of anxiety and apprehension can we mitigate ‘previous HSI’ as a risk factor? Food for thought..

What about fatigue and eccentric weakness?

  • We know HSI is more likely to occur towards end of 1st half & throughout the 2nd half (Ekstrand 2011) and that optimal time for full physiological recovery is 72 hours (Dellal et al 2013).

We also know..

  • The widely documented success of the Nordic Curl programme and other eccentric lengthening programmes in reducing HSI in some populations (Arnason, 2008 and Askling 2013).

Throughout the competitive season, the clinical challenge is to address both fatigue and eccentric strength, because for me, the 2 are counterintuitive to one another. You cannot perform regular, effective eccentric strength training without inducing fatigue, therefore it becomes very difficult to address both variables during a season of heavy fixture congestion.

I do wonder if we spend too much time in-season, prescribing injury prevention programmes and exercises. I feel there is a strong argument that we are only exposing our athletes to a greater risk of injury by adding to the overall accumulative training load and fatigue.

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Are we doing too much?

Why are we not reducing hamstring strain injuries?

Are we trying too hard in search for that holy grail of HSI prevention? Do we just need to ease off these guys?

Ultimately, and realistically I think there has to be a fine balance between the 2 . Windows of opportunity, such as the international breaks and pre-season, should be fully utilized for specific strength training and the remainder of the season used to ensure players have adequate time to recover and prepare physiologically for upcoming competition.

 

No answers here, just some food for thought. Enjoy your sport =)

 

Jonny

Motor learning theories – why should progression stop at physical?

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As a younger physiotherapist, I don’t think I ever consciously paid attention to the psychological aspect or power of my job. By that I mean, I didn’t read any research around it – it all seemed a bit wishy-washy and non-tangible. But quickly you realise that a verbal cue that just clicks with one patient turns into a complex dance choreography with another.. “No, I just wanted you to bend you knee.. why are you doing the worm?”

I’ve talked before about the clinical reasoning behind exercise progression and regression and in doing so, I skimmed the surface of the addition of intrinsic & extrinsic stimuli.  So now I want to build on the concepts of motor learning to underpin that exercise progression.

My inspiration for this blog came from a couple of podcasts by the PT Inquest gang, Erik Meira (@erikmeira) & JW Matheson (@EIPConsult). Well actually, first I bought a chinchilla, then I wrote this blog. If that doesn’t make sense, don’t worry. It doesn’t. But listen here (PTInquest).

Funny chinchilla1

The gents speak in detail on two particular podcasts about non-linear pedagogy and how this teaching concept & theory of motor learning ties in with implicit learning. I will break down the idea and definitions shortly, but the reason I wanted to blog about this rather than just direct listeners to the podcast, is I feel the motor learning concepts need to be progressed just as much as the physical demands of an exercise are considered.

explicit

What are we talking about?

Ok so breaking down some of the terms. Because from first hand experience, these terms can be confusing. Cap in hand moment but, I Published a model to explain exercise progression (here). You will see I have described implicit & explicit learning – where in fact I mean intrinsic and extrinsic. Very different things, here’s why:

Intrinsic exercises – relies on internal feedback mechanisms, such as capsuloligamentous structures – Pancian & Ruffini receptors within joint capsules providing proprioceptive feedback that the athlete is acutely tuned into. A good example is a single leg stand where the athlete is consciously thinking about balance, aware of every movement in the foot & knee, the upper body and arm position etc – those exercises where nothing else in the room matters apart from the mark on the floor you are concentrating on to keep your balance.

The opposite to this are Extrinsic exercises – these revolve around the athlete and their environment. A snowboarder reacting to a sheet of ice after carving through powder, or a downhill biker absorbing the changes in terrain – their thought process is very external. Its about the factors they can’t control. At no point (or at least for an extremely limited time) are they consciously aware of their scapular position or degree of knee valgus, for example.

Explicit teaching – This is probably something that is easy for us to relate to. It’s a teaching technique that most of us are comfortable with because we can achieve quicker short term goals. “I want you to put your feet shoulder width apart” or “keep your knees in line with your second toe during the squat” – very clear instructions that require the athlete internalise their thoughts, suddenly their actions become intrinsic. But we get quick results in line with our (not necessarily their) goals.

Implicit teaching – this is a bit more tricky. It is giving the athlete non-directive instructions with the aim of externalising their thoughts. “When you jump onto that box, I want you to land as quietly as you can” or as the PT Inquest lads say “Land like batman” (in the batman voice). If you are encouraging effective change of direction, Conor always says “Push the ground away with your foot.” We are still giving instructions, but the athlete is thinking about external environment; noise, surface contact etc.

And this is where non-linear pedagogy comes in. Creating learning environments for athletes to explore movement variability. After all, that perfect text-book single leg squat we spent weeks mastering isn’t going to look so perfect on a skier trying to regain their balance. Chang Yi Lee et al (2014) use the example or learning a tennis stroke – comparing linear pedagogy of prescriptive, repetitive drills versus non-linear pedagogy of more open instructions like “make the ball arc like a rainbow.”

Think shoe lace tying - easier to learn with the rabbit going round the tree etc
Think shoe lace tying – easier to learn with the rabbit going round the tree etc

 

How does this fit into progression?

The ideal scenario is for the athlete to have as little reliance on us as therapists or coaches as possible. We wont be following them around the track, or on the pitch reminding them of their pelvic tilt.

I think the concepts of non-linear pedagogy are brilliant to explore with coaching. Working with young athletes for example that are still developing their motor control and have some fantastic imaginations to tap into.

However with a rehabilitative role, I think we need to be more inclusive of all concepts. Learning of a new task is initially rapid but without the addition of further stimuli it can quickly plateau (Gentile 1998). A rehab program should always be low risk, high demand (Mendiguchia & Brughelli 2011).Consider the pathophysiology and the structures injured. No injuries happen in isolation, if muscle is injured we will have some neural limitations also. The presence of swelling and inflammation decreases cell metabolism along with a decrease in the presence of oxygen; so we can assume that proprioception is reduced and risk of secondary injury is high.

Therefore, following injury, it is always a good concept to assume that skill level has regressed to novice, regardless of the level of athlete pre-injury.

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“So whats the knee brace for?”                                             “Well you only had your surgery 2 weeks ago – just being safe”

What if we were to encourage intrinsic, explicit, linear pedagogy exercises in the early stages? We don’t need to be adding external stimuli at this stage. It’s important to internalise in order to rehabilitate proprioception. You can’t safely expect someone to externalise while proprioceptively deficient – as soon as someone can weight bear, we don’t start throwing them a tennis ball whilst stood on a Bosu (I hope!)

As the injury improves and skill levels progress, it is then important to move our instructions towards non-linear pedagogy methods, encouraging extrinsic thinking via implicit instructions. By end stage rehab, our instructions should be “start – stop” and hopefully not much more.

Just as we would progress the demand of physical activity following injury, we should really progress the cognitive demand also – but we need to start from a safe, effective position in acute stages.

Yours in sport,

Sam

Walking the “Plank” with core stability prescription

My colleagues are currently taking great pleasure in including “clams” in their exercise programs just to wind me up, so thought it was about time I gave them some new material. (See my thoughts on clams here).

Like “Clams” I have similar opinions on the rational behind including “planks” as part of an exercise prescription for athletes. I will start, and re-iterate later on, that there are times when they are appropriate, providing they have been clinically reasoned. But this is my point, do we throw them into rehab plans / injury prevention plans out of habit or have we individualised the exercise for an athlete?

 

walkingplank

 

What are the benefits?

Performed properly, the Plank is an isometric exercise that crudely speaking, activates the “core”. In doing so, it should encourage a sustained hold of a posterior pelvic tilt and neutral spine for a set duration of time, also working the shoulders and lower limbs to support the torso. Stability provided by the trunk muscles allows for whole body dynamic balance (Anderson & Behm 2005) and as such, these muscles require both strength and endurance.  The deep stabilisers of the lumbar spine display a small cross-sectional area, as such their ability to generate any torque is limited, so their function is to provide local stability and require this endurance component we talked about – perfectly targeted by a well performed plank. In patients with chronic low back pain, isometric exercises had positive effects on increasing the cross-sectional area of the multifidis muscles (Danneels et al 2001).

If we apply the principle of Optimal Loading, then there may be examples of injury where a static exercise is the only way of applying load to an individual. It may be that they are limited with any rotational components of exercise and are pain free in a neutral position. We also understand that isometric contractions can have an analgesic effect on patients (Bernent et al; Huber et al), hence the popularity of adductor squeezes for adductor tendinopathies.

 

..So what is wrong with Planks?

There are undoubtably examples and case studies where the use of a Plank is appropriate for an exercise program. However, un-supervised, there are many compensation patterns that patients can adopt when performing this exercise.

If prescribed as a home exercise, you should have great confidence in the athletes proprioception and ability to self correct. Otherwise you will likely re-enforce the exact reasons why you are treating the athlete in the first place. My biggest gripe with Planks, or Side Planks, or any isometric core exercise is that most people will fixate instead of stabilise. Locking the back into extension (plank) or into side flexion (side plank), or tilting the pelvis anteriorly, or flexing through the thoracic spine are examples of relying on passive structures like ligaments and joint capsules rather than stimulating active structures that should stabilise these joints.

“Don’t replace STABILITY with FIXATION”

Core stability is “the product of motor control and muscular capacity of the lumbo-pelvic-hip complex” (Click here for an excellent core stability review by Paul Gamble). The clue in this quote are the the words “stability” and “motor control”. There are very few examples in sport or even in daily living where we need to hold a whole-body isometric contraction for 1 minute or more. Essentially movements in sports occur in multiple directions. Even in events like Skeleton or Luge, the athletes are reacting to perturbations from the track or adjusting their course via small shoulder or lower limb movements, so I’m struggling to think of the cross-over benefits of a plank into sport. The benefits of a strong lumbopelvic region help transfer ground reaction forces to produce movement and integrate the function of the kinetic chain. Weakness or dysfunction of any link in the chain can increase risk of damage to another structure and as such, any one muscle should not be views a more important to another in terms of lumbopelvic stability (Brown 2006).

 

Note the increased Lumbar lordosis due to extension at the head end of the tiger
Note the increased Lumbar lordosis. Also, the stripy athlete underneath is rotated slightly.

 

“Don’t give me problems, give me solutions”

As I said, in principle there are he benefits to core stability, especially in terms of proprioception and limbo-pelvic dissociation. But for me, the trick is to stimulate the core during movement.

Some simple modifications of the Plank can greatly enhance its suitability for athletes.

 

1) Plank with Wall Taps:

Assume the traditional Plank position, you can regress this with bent knees, similar to a press up regression. Position the athlete about 2ft from a wall, facing the wall. Ask them to reach forwards and tap the wall with alternating arms but maintain stability of the pelvis and trunk.

Although a sagital plane movement, the athlete will be working against a transverse plane to stop the pelvis and lower trunk from rotating to the side of the moving arm.

photo 1[4] photo 2[4]

 

2) Plank with Stacking

Again, in a traditional Plank position, but this time set up a stack of 3 x 2.5kg weight discs on one side of the athlete. Ask them to reach over with their opposite hand, pick up a weight and start stacking on the opposite side. Repeat until all weights have transferred sides, then begin with the other arm. In doing so, instruct the athlete to stay as still and controlled in the hips and lumbar spine as possible, the movement should come from the shoulders only.

By reaching across with one hand, you are de-stabilising the torso. Moving the weight from one side to the other adds a transverse element to the exercises, as well as the challenge of moving with and without a weight.

 

photo 3[3] photo 4[1] photo 5[2]

 

 

3) The Side Plank with arm tucks:

Add an element of upper body rotation whilst stabilising the pelvis. Instruct the athlete to keep their hips up (relative hip abduction of the lower leg), tuck their extended top arm underneath themselves (like putting on a seatbelt) but in doing so, don’t let the pelvic twist. Encouraging dissociation of the pelvis and spine to stop them moving as one column.

 

photo 1[3] photo 2[3]

 

There are so many variations that I haven’t included; you can add cables or theraband and ask the athlete to pull  in different directions maintaining the plank position, you can add movements of the lower limb or think of various ways to de-stabilise the more advanced athletes. For those athletes that just “get it”, there are brilliant variations of the Bear Crawl which may be appropriate – for me, a perfect example of “core stability” (averagely demonstrated below)

– Bear crawl core stability exercise

 

Conclusion

Activities during sport require both static and dynamic strength – however in rehabilitation, these should be dynamic exercise with a pause rather than prolonged holds. At times, we may have to regress back to its most simple form in order to educate the athlete on correct positioning or increase proprioception but there should always be a plan to progress into dynamic core stability, rather than progressing the time holding a plank.

When designing rehab programs, we should always consider the individual – what do they need to cope with for their sport / daily life? What physical capabilities do they have at this moment of their program? Am I challenging them appropriately?

I hope this provokes some thought and discussion, please let us know your experiences and opinions

 

Yours in sport,

 

Sam

 

Exercise Progression & Rehab Programs

A year or so ago, I put on a CPD evening for our part time staff at the football club discussing exercises and the clinical reasoning behind developing a program (needless to say I got talking about the use of clams for a quite a while – clam blog). In this presentation, I started drawing my reasoning process onto powerpoint using some coloured blocks to help visualise the theory that I was trying to describe.

The theoretical model was recently published in Physical Therapy in Sport and I thought I would use this blog to try and discuss it in a less formal way than the writing style allowed in publication.

 

The model (here) is designed to be fluid and adapted to any individual by any level of clinician. Let me quickly introduce the components:

Model
A theoretical model to describe progressions and regressions for exercise rehabilitation (Blanchard & Glasgow 2014)

 

  • The triangular blocks (1) represent the fundamental exercise, the core ingredient that will remain throughout the progression. The arrows running up the side of the triangles represent an ongoing progression throughout the rehab process such as speed, duration, repetition etc. So basically, something that can’t be affected by the stimuli that are added or removed. If you add an unstable surface to an exercise, you can still progress by increasing the duration.
  • The coloured blocks represent a stimulus that will help the exercise progress. This can be one of two things;
  1. Internal – something that the patient has to focus on intrinsically. A decreased base of support for example, where the patient must focus on the balance element of an exercise.
  2. External – the addition of something to the exercise that takes the patients focus away from the movement or action they are performing – adding a ball to a running drill, or a verbal command that initiates a change in direction.

The blocks are interchangeable and can be added / removed at the clinicians discretion.

  • Adding a new block, which will progress the exercise, is accompanied by a regression of the “gradient” on the blue triangle. Creating a step-like progression across the model. As you progress with an internal or external stimulus, its important to bring the difficulty levels back down, so reducing repetitions or speed or duration. This allows the pateints to adjust to the new stimuli without fear of re-injury or task failure. When teaching a child to ride a bike with stabilisers, you don’t take them off and ask them to cycle at the same speed you did with them on. For that reason, you wouldn’t get someone going from 30 reps of a hamstring bridge straight into 30 reps on a single leg bridge as a progression. You would decrease base support and reduce reps to allow adaptation.
  • Adding a “block” doesn’t mean you have to add something to the exercise. The block represents a step up in their progression. So progressing from two legs to single legs is technically “taking away base of support” but is an addition to the ongoing progression.

 

Lets use an example, recently I started designing a program for a teenage footballer with a proximal adductor strain. New to professional football with no history of conditioning.

In the sub-acute stage, once intial pain had settled, we began looking at his movement patterns and stability and noticed a huge imbalance with his left sided control through sagittal and transverse planes compared to his right. He is left footed, so his plant leg (right) is used to supporting his body weight.

His body awareness and “physical literacy” was so poor we had to regress him right back to basics. The following represents a small proportion of a larger exercise program. I’m not usually an advocate of planks in a multidirectional sport like football, but in this case, his single plane control was so poor that I swallowed my pride and began with basic planks.

imagesCA39QJMI

When I say basic, we reverted to short lever planks with the knees on the floor – this was the only was we could get him to control the relationship between his trunk and pelvis. Looking at the model, this short lever plank would be the singular blue triangle at the start (1). We built up the duration of the hold from 30 seconds to 90 seconds over time. This would be the arrow running up the gradient of the triangle.

 

The addition of the first block (2) was to increase the length of the lever so that he now has to hold a traditional plank. In doing so, we dropped from 90s hold back down to 30 seconds and over time, built up to 90s. (These are just arbitrary times, based on no real evidence).

 

The next block we added was a rotational element (3), but to ensure the progression wasn’t too sharp, I removed the long lever and returned to a short lever position. I then asked the player to move a light 1.25kg weight from his left side, with his right hand and place it on his right side. Then with his left hand etc etc. The purpose of this was to introduce a transverse task to a sagittal plane activity – as the arm moves from the ground and across the body, the player has to control the rotation through his trunk and avoid rotation at the pelvis. Instead of duration, we built up repetitions over time.

 

Now that we were confident he could hold a plank, and control rotation in a short lever plank, we could combine the two blocks as the next progression. Now in a long lever plank with a rotational element.

 

The next progression was to add an unstable surface (4). To do this, the player performed a plank with his thighs on a gym ball. This in itself was quite easy so we instantly added a rotational component with an unstable surface, gym ball pelvic rotations (see video here). So now on the model, we have the basic “plank” triangle at the top, a block underneath to symbolise the long lever, another block to symbolise rotational control and a third block to symbolise an unstable surface.

 

“The length of time required by an individual to master a task has

been described as a linear function that begins quite rapidly with

the introduction of a new task and then plateaus or slows over time

as practice continues (Gentile, 1998).”

 

 

This is a very simplistic example of how the model works, but hopefully it demonstrates the fluidity that is intended with it and how the blocks are interchangeable and can work independently or as part of a more complex progression. Every program you write will be individual and the progressions will be different, therefor every model will look different. Some will continue longer than others, some may be shorter than the one I’ve described here. Some will end up with taller columns due to the number of progressions. The width of one column compared to its neighbour may be different size due to the length of time it takes for the patient to master. And so on and so on. If I continued, hopefully I could have ended up with the player doing this:

imagesCANGK06X
But whats the use of that defending a counter attack?

 

Like many conversations I begin or poor jokes I tell, this may be one of those things that only makes sense in my head, but I would love to hear if it makes sense to others – if you think it works and examples of doing so.

 

Yours in Sport

 

Sam