Our good friend, Bill Katovsky of http://zero-drop.com, did an awesome expose of wild and crazy shoes! If you are unflamiliar with Bill, or his work, please visit his site!
Thanks for the entertainment, Bill!
Ivo and Shawn
As promised. The info you need to make an educated decision about your training.
What is lactate testing?
Lactate testing is a highly scientific, reliable and accurate way of looking inside the body during exercise to see exactly what’s going on physiologically. At its simplest, lactate (a salt) is a by-product of lactic acid, which is produced during exercise, especially at higher intensities. It’s not necessarily bad or good, but it is of key importance when you are looking to improve as an endurance athlete.
To better understand it, some key points are best made from the start because, all lactate testing is not the same and as a consumer you must be careful to learn the facts before you get tested:
Ø Unless you are getting blood lactate measured through blood samples taken during exercise, you are not getting a true lactate test and you cannot get accurate, valid & complete results.
Ø Lactate is a key player in endurance performance. It is far more important than VO2 max as it is directly related to your ability to perform at race pace.
How does blood lactate testing compare to other testing methods?
Lactate testing removes the guesswork and estimation that many other testing methods use and is based solely on the data that your body provides. Anaerobic threshold prediction tests, max heart-rate tests and heart-rate formulas are all based on guesswork and mathematics and as such don’t always give the most accurate results.
After being lactate tested and comparing the results with those from a heart-rate formula or anaerobic threshold prediction test, it’s not uncommon for some athletes to realize that they’ve been training as much as twenty beats per minute out of their optimal range! Suddenly the athlete can see why they were prone to over or under-training, underperformance and constant disappointment.
Almost always, the athlete improves dramatically following lactate testing as for many this is the first time that they get accurate data that allows their true athletic potential to be realized.
With lactate testing your training zones are based on the exact concentration of lactate at certain exercise intensities and the corresponding heart-rates, power outputs and speeds. These are different for everyone. There is no 85% or fat burning zone, just unique and personal results specific only to you based on sound science.
Regularly performing true lactate tests on athletes allows you to:
1. Monitor the balance of the aerobic and anaerobic systems
2. See how your body has adapted to training
3. Allow your body to tell you what training it needs
4 Develop accurate training parameters to bring about optimal progress for you
How can a lactate test help you?
Lactate testing is vital for the optimal development of an endurance athlete. At its best, it gives you precise heart-rates and training parameters like power output and speeds that are not available from any other method. Furthermore, you learn what training works for you and also learn what doesn’t work. It saves you from repeating mistakes and wasting time. For example, imagine getting 6 weeks in to a 12 week training program and doing a repeat lactate test. Imagine that the test tells you that your aerobic system has not improved sufficiently enough for the planned increase in volume that you had in mind. That’s information that you need to know. You can now change your training plan to reflect what you’ve learned, so that you continue to progress over the next 6 weeks and so that your racing experience is more successful.
What if you hadn’t done the test?
Chances are, you’d have ploughed through the increased mileage, overstressing an already weak and undeveloped aerobic system and ended up getting slower and slower, even over-trained. The race would pass miserably and you’d be left wondering what happened.
Is lactate testing only for elite athletes?
Lactate testing is just as important for the Novice athlete as it is for the Elite athlete. If you are genetically gifted, you can get to high level in endurance sports based on what you were born with. At the elite level, lactate testing helps refine training and improve already high standards. At the Novice or Age Grouper level, genetic talent is limited so you need to maximize what you have.
With blood lactate testing you optimize your training so that every second counts and you maximally develop your potential to its highest possible level.
Can you improve without lactate testing?
Of course you can, but how much guesswork are you willing to involve and how much time do you have to waste? Let’s face it - training is hard work. It’s not always fun so you want to guarantee that what you do works for you optimally. You want to make the most of the time that you have available. You can wander through the various books and pick up new ideas and try things but the reality is that the fastest way forward to peak performance, National team qualification, Hawaii ironman qualification and everything you want from your sport, is through rapid and continual development. That comes from good planning and monitoring the success of your training.
Sifting through the science, so you don’t have to. we are: The Gait Guys
The information you have been waiting for. How do you facilitate a muscle? How do you defacilitate a muscle? Do you already know how? Do you know the mechanism?
Fear not… In this weeks Neuromechanics, Dr Waerlop simplifies the function of Golgi Tendon Organs. Clinical correlations are made throughout the presentation with his usual sense of humor. Neuro and foot geeks around the world are rejoicing…
Wow, we really are geeks!
Mov Disord. Author manuscript; available in PMC 2009 February 15.Published in final edited form as: Mov Disord. 2008 February 15; 23(3): 329–472. ____________________________________________________________________________
Executive function (EF) refers to an assimilation of numerous higher central nervous system cognitive processes from various regions of the brain in order to process, manipulate and generate behavior. Dr Ivo talked about this in some of the recent Neuromechanics lectures as the “Central Integrated State”.
This study suggests that people with gait abnormalities are much more susceptible to developing dementia. As they say here , “subtle gait changes predicted the subsequent development of dementia." This kinda makes what The Gait Guys are trying to bring to light, well … , pretty darn important for us all ! The study also suggested that those that walk daily, as a form of exercise we are assuming, significantly reduced this risk compared to those who were more sedentary.
This study postulates that gait, daily walking, uses Executive Function (EF) in the brain and thus if someone refrains from daily activities such as gait that EF will diminish. And since EF loss and dementia see parallel, the less active we are, the more the risk for dementia. So the old adage "if you don’t use it, you lose it” applies here.
The study does point out that the relationship between walking and cognitive function is multifactorial. The study seems to suggest that there could be a relationship between dual tasking gait abilities and the development of dementia although studies are not yet available. Remember that the brain works best when running parallel tasks, rather than unitasking. Studies seem to suggest that the cerebellum is involved (with learning), and thus a gravitational activity like gait certainly would apply.
Now, we are sure they are not talking about walking and juggling chainsaws but they could be eluding to conscious awareness of corrective gait exercises such as those we use in our office with our patients to cue certain corrective patterns however they very well mean engaging in stimulating conversation with someone while walking might fit the bill.
They make this suggestion when they discuss the fact that attention demanding tasks change the walking pattern in subjects and thus an alteration in Executive function (EF) but they also mention that a change in executive function will also change walking patterns. So, it appears it is clearly a two way street. We see these things in our office, and you will see them in your patients and athletes. With a change in information or a change of focus, you see a change in patterning because EF has had a demand change. When we have patients doing a gait patterning exercise and we suddenly ask them what they had for lunch, basically engaging either a memory or a spacial-temporal memory, their gait pattern reverts to the older established pattern we are trying to amend.
As the study summarizes, “a causal relationship between EF changes and gait changes remains to be more firmly proven, however, there is ample evidence demonstrating a relationship between these two seemingly disparate domains including numerous investigations which have documented changes in the gait pattern in response to dual tasking. This dependence is most notable in patient populations where the ability to compensate for an impaired gait is restricted to due a lack of “cognitive reserve.”
This study has pertinence on many levels. From athletes, to elderly with the risk of falls and dementia and possibly on the subconscious levels of learning.
we highly suggest you obtain this article for your archives.
Shawn and Ivo, The Gait Guys……. looking at how we move from every aspect……from the brain to the toes.
AUSTIN, Tex. (Sept. 6, 2011) - It’s been called the four most important days in the running business. For four days, the Austin Convention Center and the Hilton Austin will host well over one thousand running specialty vendors and business leaders to The Running Event® (www.therunningevent.com). It’s the first opportunity for retailers to see the latest footwear, apparel and accessories for fall 2012.
The conference portion of The Running Event on Dec. 7 and 8 focuses on retailer education, sales training and business growth, featuring speakers such as Gene Marks, columnist for Businessweek, Forbes and The New York Times; a panel discussion with representatives from Fleet Feet, Naperville Running and Salt Lake Running Co.; and Dr. Shawn Allen, co-founder of The Gait Guys.
The Expo runs from Dec. 8 to 10, and with over 200 exhibitors is the largest in the show’s six-year history.
2 links:
Lets take another look at yesterdays post “the Single leg squat” from a little different perspective….
Watch carefully. Did you pick up the bunion forming on both feet (Hallux Abducto Valgus)? This tells us that this individual has a faulty foot tripod, and is not able to get the base of the first metatarsal to the ground (remember the tripod is the base of the 1st metatarsal (big toe), the base of the 5th metatarsal (little toe) and the center of the heel). As a result, the muscles which are supposed to be assisting in forming the longitudinal and transverse arches are pulling the big toe (hallux) laterally. This also means that the medial side of the tripod is collapsing. This can be seen at :05 as she descends into the squat. You will also notice that this drives the knee medially and is causing some collapse of the arch. You also see the big toe flexing to try and create some arch stability through the flexor hallucis brevis.
As Dr Allen Points out, keeping the arch stable requires core stability, muscular strength and good proprioception. It also requires adequate flexibility (ie Range of Motion) of the 1st ray complex (the proximal and distal phalynx of the great toe and the 1st metatarsal). This range of motion can be seen from :12 to :20 and again from :42 to :51
Sorting through the subtle…We are The Gait Guys,
Ivo and Shawn Two docs out there making a difference
(visit our blog daily at www.thegaitguys.tumblr.com)
How to (and how not to) do a single leg squat, CORRECTLY !
Here Dr. Allen has one of his elite marathon and triathletes demonstrate how to correctly and incorrectly do a single leg squat. The single leg squat can show many of the pathologic movement patterns that occur in a lunge. The single leg squat is more difficult however because it requires balance and more strength. Many people do not do the single leg squat correctly as you will see in this video. Many drop the opposite hip which means that there is an inability to control the frontal plane pelvis via the stance leg gluteus medius and the entire orchestrated abdominal core. Most folks will drop the suspended hip and pelvis and thus collapse the stance phase knee medially. This can lead to medial knee pain (tracking disorder in the beginning) , a driving of the foot arch into collapse and impingement at the hip labrum. We know that when the knee moves medially that the foot arch is under duress. This problem is often the subliminal cause of all things foot arch collapse in nature, such as plantar fascitis to name a common one. Remember, optimal gluteus medius is necessary here. And the gluteus maximus is working to eccentrically lower the pelvis through hip flexion. So, if you do not consider the gluteus maximus a hip flexor then you are mistaken. Everyone thinks of it as a powerful hip extensor and external rotator. But do not be mistaken, in the closed chain it is a powerful eccentric controller of hip flexion and internal hip rotation.
Tomorrow we will look at this same case and look at her feet and discuss those as a problem, predictor and limiting factor to long term optimal function.
We are The Gait Guys,
Shawn and Ivo (visit our blog daily at www.thegaitguys.tumblr.com)
what we think we look like when we run is not always the case. Pictures are worth a thousand words !
Trust us, this will be something we will see in time. This brief newsflash talked about foot plantar pressure representations, but as Ivo and I know…… there is so much more to the overall gait patterning. We know, we look at it everyday.
According to the brief article, “Researchers at the University of Liverpool analyzed more than 100,000 pressure points people’s feet create when they walk and came up with about 70 patterns said to be unique to any one individual, The Daily Telegraph reported.
The researchers said the findings could add another type of "biometric” identification in addition to retinal scanning and fingerprints at airports and in other security settings.“
Gait Forensics labs……. you might want to look at our body of work…… we kinda know what we are doing.
Shawn and Ivo, quite possibly, future experts in Gait Forensics.
speachless……. brilliant
Check this guy out! we hoipe we are still running when we are his age…
Hope you are enjoying the weekend!
Ivo and Shawn
Our brief mention in Sept 16th issue of Triathlete magazine
link is above….. Jene Shaw the editor did a nice job on a touchy subject.
Although they date back to King Tut and Cleopatra, your favorite thong-style sandal may be bad for your running health according to biomechanical experts The Gait Guys (Thegaitguys.com), Dr. Shawn Allen and Dr. Ivo Waerlop.
In 2008 Auburn University researchers found that wearing flip-flops alters your gait, which can result in biomechanical issues from your foot to your spine. “In flip-flops the kinetic chain is essentially asked to function differently,” Allen says. “They can force changes in step and stride length, reduce function of the glutes, and compromise lower leg and foot intrinsic muscles, to name a few.”
When wearing flip-flops, use of the foot intrinsic and toe extensor muscles is reduced in the stance phase of gait. What’s important about this is that the toe extensors, found in the lower leg, are synergists for ankle dorsiflexion (the upward movement of the foot), which is key in running. Without ample function of these muscles, the toe flexors, calf and Achilles shorten and tighten, which impairs optimal ankle and foot joint function.
3 strikes against flip-flops:
• Without sufficient strength in the anterior tibial compartment (the front of your lower leg) you are at risk for several problems, including shin splints.
• Lack of adequate function of the toe extensors can lead to toe flexor dominance (look to see if your toes have a gentle curl to them at rest; if so, you are in that group!) which has implications with general weakness of the foot muscles responsible for arch strength and general foot health.
• In order to keep a flip-flop on our foot, we tend to grip with our flexors, which forces us deeper into this scenario.
If you are going to wear sandals and you want healthier feet, The Gait Guys recommend wearing sandals that have straps that fasten to your heel or lower leg.
We don’t dig the music, but lots of shoes and entertainment factor here!
Have a great Friday!
Ivo and Shawn
This is a nice study looking at lateral gastroc activity and changing firing patterns with speed of movement. It also melds nicely with yesterdays Neuromechanics post…
Those darn Ia afferents….
You remember them, large diameter afferent (sensory) fibers coming from muscle spindles and appraising the nervous system of vital information like length and rate of change of length of muscle fibers, so we can be coordinated. They act like volume controls for muscle sensitivity. Turn them up and the muscle becomes more sensitive to ANY input, especially stretch (so they become touchy…maybe like you get if you are hungry and tired and someone asks you to do something); turn them down and they become less or unresponsive.
Their excitability is governed by the sum total (excitatory and inhibitory) of all neurons (like interneuron’s) acting on them (their cell bodies reside in the anterior horn of the spinal cord).
If we slow things down, the rate of change of length slows as well and excitability decreases, like we see in this study (3-6% slower). We also notice that the length of contraction increases; hmmm, why doesn’t it decrease?
Remember these folks are on a treadmill. The treadmill is constantly moving, opposite the direction of travel. With the foot on the ground, this provides a constant rate of change of length of the gastroc/soleus (ie, it is putting it through a slow stretch); so , once the muscle is activated, it contracts for a longer period of time because of the treadmill putting a slow stretch on the gastroc (and soleus).
This article also talks about people with upper motor neuron lesions. An important set of inhibitory neurons come from higher centers of the brain, in the motor cortex. These tend to attenuate the signals affecting the Ia afferents, and keep us stable. When we have an upper motor neuron lesion (like a brain lesion or stroke), we lose this “attenuation” and the stretch reflexes (and muscle tone) becomes much more active (actually hyperactive), making the muscle more sensitive to stretch. This loss of attenuation, along with differing firing patterns of the gastroc are important to remember in gait rehab.
The soleus and medial gastroc begin firing in the first 10% of the gait cycle (at the beginning of loading response) and fire continuously until pre swing (peaking just after midstance). The lateral head begins firing at midstance; both leads (along with soleus) decelerate the forward momentum of the tibia, flex the knee at midstance, and the medial head assists in adducting the calcaneus to assist in supination.
We remain, inexplicably….The Gait Guys
Effects of treadmill walking speed on lateral gastrocnemius muscle firing.
by Edward A Clancy, Kevin D Cairns, Patrick O Riley, Melvin Meister, D Casey Kerrigan
American journal of physical medicine rehabilitation Association of Academic Physiatrists (2004) Volume: 83, Issue: 7, Pages: 507-51 PubMed: 15213474
OBJECTIVE: To study the electromyographic profile-including ON, OFF, and peak timing locations-of the lateral gastrocnemius muscle over a wide range of walking speeds (0.5-2.1 m/sec) in healthy young adults. DESIGN: We studied gastrocnemius muscle-firing patterns using an electromyographic surface electrode in 15 healthy subjects ambulating on a treadmill at their normal walking speed and at three paced walking speeds (0.5, 1.8, and 2.1 m/sec). Initial heel contact was determined from a force-sensitive switch secured to the skin over the calcaneous. RESULTS: For all speeds, the gastrocnemius firing pattern was characterized by a main peak, occurring 40-45% into the gait cycle, that increased in amplitude with walking speed. Speeds of > or =1.3 m/sec produced a common electromyographic timing profile, when the profile is expressed relative to the stride duration. However, at 0.5 m/sec (a speed typical of individuals with upper-motor neuron lesions), the onset of gastrocnemius firing was significantly delayed by 3-6% of the gait cycle and was prolonged by 8-11% of the gait cycle. CONCLUSION: Many patients with upper motor neuron lesions (e.g., stroke and traumatic brain injury) walk at speeds much slower than those commonly described in the literature for normal gait. At the slow walking speed of 0.5 m/sec, we have measured noticeable changes in the electromyographic timing profile of the gastrocnemius muscle. Given the importance of appropriate plantar flexor firing patterns to maximize walking efficiency, understanding the speed-related changes in gastrocnemius firing patterns may be essential to gait restoration.
This week on Neuromechanics, Dr Waerlop discusses muscle spindles and their importance in determining muscle tone. Think about this clinical applications with gait, in light of our most recent posts
More Lactate:
Before we talk about determining blood lactate levels, we need a deeper understanding of the energy producing systems at play, as well as some commonly used terminology.
There are 2 main systems for producing energy in the body, the aerobic system and anaerobic system. There is a 3rd system, the Creatine Phosphate system, which provides energy for very short bursts of a few seconds, or until your creatine phosphate stores are depleted. we will concentrate on the 2 main ones.
The aerobic system or aerobic metabolism, utilizes oxygen, using predominately fats & some carbohydrates for energy along with recycled lactate which is produced at low levels and metabolized efficiently. This is your endurance energy system. You may still have recurring nightmares about this from freshman biology, also known as the Krebs (or Citric Acid) Cycle
Your lactate threshold (LT) is a highly aerobic point where lactate levels in the blood are still low but just starting to reach steady state levels. Your LT is the most efficient effort level that you can sustain for long periods of time without going in to your energy reserves (i.e. glycogen). Beyond this point, you are exceeding your ability to recycle lactic acid back into the Citric Acid Cycle and lactate levels begin to rise; changing local blood pH and affecting local chemical reactions.
The anaerobic system does not utilize oxygen, using predominantly carbohydrates for energy. An efficient anaerobic system will produce a lot of lactic acid as its by-product. As you know, in large amounts, this causes the burn and fatigue you often feel when working hard. Thus, your anaerobic threshold (AT) is much more stressful and is therefore only sustainable for shorter periods of time.
What does this mean?
For the endurance athlete, the BALANCE of these two systems must be developed optimally for their chosen event. Performing a lactate test (to be discussed in another post) will help determine the relative contribution of each system. In general, the well-developed endurance athlete will produce very little lactate even at high speeds. Endurance sport athletes, such as cyclists, Ironman athletes, triathletes and top marathon runners need to be highly aerobic, which means that very little lactate is produced even at peak speeds and testing reveals a very flat lactate curve. Most of their energy comes from aerobic sources.
Optimizing lactate threshold development is the main goal of endurance training, and racing at or near LT proves the most efficient route to a solid race day performance.
So, how can you use this information for training? Watch for an upcoming post on Lactate testing.
Yup, we know a thing or two about gait AND training.
The Gait Guys: Ivo and Shawn
The Ankle-Foot Orthosis : Another option for foot drop.
Do you have a client who suffers from some foot drop ? Do they have a classical AFO but it drives them nuts ? Foot drop occurs when the anterior compartment of the lower leg (mostly tibialis anterior and/or long toe extensors) gets compromised neurologically leaving a persons gait compromised during the swing phase and early half of stance phase. Early to mid stance phase of gait requires that the anterior compartment muscles slowly (eccentrically) lowers the foot to the ground in a controlled manner. When this is compromised the foot quickly, and without strategy, slaps to the ground thus rushing the persons gait onto the forefoot. This often occurs in an uncontrolled fashion and renders some balance and weight transfer complications. Then, during late stance phase, when the foot comes off of the ground merely by forward body progression, these clients leave the foot in the pointed plantarflexed position leaving the toes without proper clearance. This often leads to tripping and stumbling.
Always looking out for newer and better solutions, we came across this variation on the AFO (ankle-foot orthosis) strategy. It seems like it could have some advantages from a logistical side. Whereas the typical AFO comes under the foot and maintains the foot in a 90 degree ankle rocker (dorsiflexion) position this one has a bit of a dynamic effect. The bungee cord-like device should slowly lower the foot to the ground as well as help to spring the foot back into dorsiflexion for swing phase clearance so that the toes are not catching on the ground. Seems so simple we have to wonder. We might give this one a try on a few patients who have varying degrees of footdrop and report back.
Regardless, we wanted to share……. we love outside the box thinking. Especially when it is so simple !
bravo !
shawn and ivo…………. toss in a side of orthopedics and a main course of neurology, sprinkle a little biomechanics on that and you have a well rounded meal. We are …… The Gait Guys
Parkour Running: Taking gait and running to another level.
Nike Commercial: How to outrun a chicken .
Sebastian Fouucan vs. David Belle
Pants around your thighs. We have this gangster gait on our list of things to do.
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