How many of you are using a microwaves to prepare or re-heat food ?

I know I use one almost daily, being in the gym from 7am till 9pm sort of forces you to!

Anyway as ever I was doing some reading and found an excellent piece on the subject area and though I needed to share it with you

Click here to go to full review

However here’s the recommendations if you are to lazy to read the whole thing :

Summary and Recommendations:

Microwave ovens usually don’t destroy nutrients in food. If using a microwave helps you eat more nutritious foods and less junk food, then keep it. But there are potential harmful effects from too many electromagnetic frequencies, and doing without a microwave is one way to limit exposure.

If you use a microwave:

• Don’t heat food in plastic.
• Make sure food reaches 160 degrees F in all areas (you have a food thermometer, don’t you?).
• Cover food to help ensure uniform cooking.
• Allow the food to sit a few minutes after microwaving.
• Microwave food only as long as necessary, with little to no cooking water.
• Keep the microwave out of high traffic areas.

If you don’t use a microwave:

• You can eat leftovers cold. If you don’t have to reheat – don’t. Each time we reheat, no matter the method, we are going to lose nutrients.
• Try the stove, including steaming or stir-frying.
• Use the oven, including baking and broiling.
• Consider a toaster oven, which uses less energy than a conventional oven. (Heck, consider a solar cooker. Just sayin’.)
• Heat water in an electric tea kettle.

It would be great to hear your thoughts and comments on this interesting area.

Written By Nicholas Jones DNA Sports Performance Director

Muscle strength imbalances occur when one muscle or group of muscles are overloaded. This may not sound serious; however it can lead to a variety of problems including reduced performance and increased injury susceptibility.  For example Orchard et al., 2002 surveyed injuries in Australian first class cricketers and found that “the most common injuries suffered were hamstring strains, side strains groin injuries, wrist and hand injuries and lumbar soft tissue injuries”.

The question on every coach’s mind is whether or not to integrate prehabilitation exercises into their exercise programme to reduce their predisposition to injuries caused by overloading or to change loadings of performance improvement exercises.

It is suggested that muscle strength imbalances are common in most athletes.   For example tennis players are susceptible to shoulder injuries in their dominant arms.  Chandler et al., 1992 suggested that “external rotation strengthening exercises should be implemented in tennis conditioning programs to maintain muscle strength balance, and possibly reduce the chance of overload injury”.

Knapik et al., 1991 completed a study on female college athletes and suggested “there was a trend for higher injury rates to be associated with knee flexor or hip extensor imbalances on either side of the body and that specific strength and flexibility imbalances are therefore associated with lower extremity injuries”.

McMaster et al., 1991 evaluated the isokinetic strength of the rotator cuff in elite water polo players and found that “the water polo players were significantly stronger than the controls. Of greater importance was the confirmation of imbalances in the rotator cuff force couples of adduction/abduction and external/internal rotation”.

The answer to this earlier question is that prehabilitation exercises should undoubtedly be integrated into athletes exercise programmes to correct their muscle strength imbalances, which will inevitably reduce their predisposition to injuries.

Functional movement screening (FMS) is the one the methods used by your strength and conditioning coach for identifying weak points/muscle strength imbalances.  “The FMS is a ranking and grading system that documents movement patterns that are key to normal function.  By screening these patterns, the FMS helps to readily identify functional limitations and asymmetries, which can reduce the effects of functional training, physical conditioning and distort body awareness”.

Here at DNA Sports Performance we work with our physiotherapists to screen our new athletes using our every own integrated movement assessment.  Some of you may have experienced this recently when you started working with us and may now be completing prehabilitation exercises within your strength and conditioning programmes.

Practical Application:

Have you been screened for identifying weak points/muscle strength imbalances recently?

If so, has your strength and conditioning coach integrated prehabilitation exercises into your exercise programmes?

If you have answered no to any of the above questions then you need to act now because an injury may be in waiting.

References

Chandler T. J et al., (1992).  Shoulder strength, power, and endurance in college tennis players.  American Journal of Sports Medicine. July 1992, Vol. 20, No. 4, Pages 455-458.

Knapik J.J et al., (1991).  Preseason strength and flexibility imbalances associated with athletic injuries in female collegiate athletes. American Journal of Sports Medicine. January 1991,Vol. 19, No. 1, Pages 76-81

McMaster, W, C et al., (1991).  Isokinetic torque imbalances in the rotator cuff of the elite water polo player.  American Journal of Sports Medicine. January 1991, Vol. 19, No. 1, Pages 72-75.

Orchard et al., (2002).  Injuries in Australian cricket at first class level 1995/1996 to 2000/2001.  British Journal of Sports Medicine 2002, Vol. 36, pages 270-274.

The focus of this blog post will be the use of sport specific skill testing and protocols designed to stimulate the physiological aspects of sport performance, and the benefits and downfalls to this type of sport specific simulation testing.

A recent protocol used to test soccer specific performance was utilised by Currel, et al., (2009), the protocol combined both the skilful aspects of soccer performance (which were measured) and the physiological aspect. Using a field test created by Ekblom (1989) the test’s intention is to simulate the physiological conditions of a soccer match. Participants complete a variety of movements (changes of direction, forwards, sideway and backwards locomotion and jumps) at a variety of intensities – walking, jogging, cruising and sprinting – that are found during a football match (Reilly & Thomas, 1976). This was done in an effort to simulate the conditions of a soccer game.

The four skills tested during this protocol are: -

• Agility, consisting of a timed run through a set course of cones.
• Kicking accuracy, where a goal is divided into 5 equal sections with the middle section being 5points, the outside sections 1 point and the two intermediate 3point and the player takes a dead ball shot from 18yards.
• Jump height, where the measurement is taken from the height of a ball suspended above the participant that they have been instructed to head.
• Dribbling skill test of a timed dribble between cones.

The tests are performed two at a time, alternately between 6-minute blocks of the field test and this is repeated for 10 intervals equating to a full 90minute match.

Although this post concentrates mainly on soccer performance testing, the theory and application are relevant for most skills based sports that involve a physiological stress. Very few testing protocols aim to combine both the physiological and technical aspects of sport; coaches instead choose to test these separately or, especially with technical aspects, not at all. However, is this a more efficient right way to test athletes? As it is the technical part of the sport that makes the difference to winning and losing, but these skills are useless if they cannot be performed in a fatigued state.

Literature Review

A few studies have tried various protocols to combine the physical and technical elements of soccer performance prior to Currel et al., (2009), including testing players’ technical performance post game (Ostojic & Mazic, 2002), a 60 minute mixed locomotion field test with kicking accuracy test (Cox et al. 2002), using the Loughborough Intermittent Shuttle Test followed by soccer specific tests (Ali et al. 2007a) and the Ball Sport Endurance & Sprint Test (BEAST90) (Williams et al., 2009.)

Furthermore, during my use of the Currel, et al., (2009) protocol I modified the duration to correspond with the participants’ usual 60minute 6-a-side competitive games. Recorded heart rates during the testing and during competitive games showed that the protocol didn’t produce high enough average heart rates compared to a real match situation (177.6 beats.min^-1 (highest average recorded) vs. 182 beats.min^-1 (average heart rate recorded during match play)).

As you can see from the table above each protocol has significant weaknesses – some of them less easily remedied than others. One of the conclusions I came to was to create a more valid test by combining the physiological protocol and testing sequence from Currel, et al., (2009) and the more valid (due to the cognitive components involved in them), skill tests used in Ali et al (2007a).

While the above protocol pros and cons are all based on soccer, they are applicable to all sports that rely on skilful performance involving open, externally paced, interactive skills combined with a strong physiological response, e.g. rugby, tennis, water polo, badminton.

Practical Application

So, the questions posed are:-

• Should coaches directly test skilful performance or rely only on match day or training subjective judgements?
• Is it possible to accurately test skilful performance e.g. Does performance in a skills test relate to improved performance in a real match?
• Should testing of skills be done in a similarly fatigued state to that experienced during a match?
• Is it possible to simulate match day physiological responses in a controlled protocol? And perhaps most importantly, is it really worth researching?
• Is it not easier for an experienced coach, with the help of performance analysts, to determine skilful performance by assessment during match play and during training? And for an expert strength and conditioning coach to test the physiological aspects of play using widely accepted specific tests that correlate well with sports performance?

My opinion is that much more research and development needs to be done in the area of skill testing before it can be replied upon for determining between players e.g. trial selection. For example, while the Loughborough Soccer Shooting and Passing Tests have been found to be reliable and valid when comparing elite vs. non elite (Ali et al. 2007b) – it is uncertain whether they could determine skill differences between a team of players of similar skill level; it is also a similar story in a range of sports including rugby (Stuart et al. 2005), basketball (Dougherty et al. 2006), field hockey (Keogh, Weber & Dalton (2003) and handball (Lidor et al. 2005). But, if skill testing is to be done then I think it is sensible to perform them in a non-fatigued and fatigued state – an individual may be able to perform skills easily and have good endurance – but unable to perform sport specific skills when tired. Furthermore, it is likely that the application of this type of testing will be more easily applied in one versus one sports, such as racket sports, or in sports where there is a lot of ‘set plays’, such as American football or basketball; as these sports are less random in nature than rugby, hockey or lacrosse, for example.

With the current research, strength and conditioning coaches should test physiological markers of sport specific performance in order to monitor training only. Sport specific coaches should determine between players for selection from observation of training and match play. However, the combination of skill specific tests with simulation protocols is an interesting concept to be explored in the future, particularly in reference to racket games and invasion games with set plays.

Leave a reply below to let me know what you think.

References

ALI, Ajmol, et al. (2007a). The influence of carbohydrate-electrolyte ingestion on soccer skill performance. Medicine & science in sports & exercise, 39 (11), 1969-1976.

ALI, Ajmol, et al. (2007b). Reliability and validity of two tests of soccer skill. Journal of sport sciences, 25 (13), 1461 –1470.

COX, G., et al. (2002). Acute creatine supplementation and performance during a field test simulating match play in elite female soccer players. International journal of sport nutrition & exercise metabolism, 12 (1), 33-46.

CURREL, Kevin, CONWAY, Steve and JEUKENDRUP, Asker E. (2009). Carbohydrate ingestion improves performance of a new reliable test of soccer performance. International journal of sport and nutrition & exercise metabolism, 19 (1), 34-46.

DOUGHERTY, Kelly A., et al. (2006). Two percent dehydration impairs and six percent carbohydrate drink improves boys basketball skills. Medicine & science in sports & exercise, 38(9), 1650-1658.

EKBLOM, B. (1989). A field test for soccer players. Science & football, (1), 13-15.

KEOGH, Justin W.L., WEBER, Clare L., DALTON, Carl T. (2003). Evaluation of anthropometric, physiological, and skill-related tests for talent identification in female field hockey. Canadian journal of applied physiology, 28 (3), 397-409.

LIDOR, Ronnie et al., (2005). Measurement of talent in team handball: the questionable use of motor and physical tests. Journal of strength and conditioning research, 19 (2), 318-325.

OSTOJIC, S.M. and MAZIC, S. (2002). Effects of carbohydrate-electrolyte drink on specific soccer tests and performance. Journal of sports science & medicine, 1 (2), 47-53.

REILLY, T. and THOMAS, V. (1976). Motion analysis of work-rate in different positional roles in professional football match-play. Journal of human movement studies, 2 (2), 87-97.

STUART, Gene R., et al. (2005). Multiple effects of caffeine on simulated high-intensity team-sport performance. Medicine & science in sports & exercise, 37 (11), 1998-2005.

WILLIAMS, J.D., ABT, G. and KILDING, A.E. (2009). Ball-sport endurance and sprint test (BEAST90): Validity and reliability of a 90-minute soccer performance test. Journal of strength and conditioning research, 24 (12), 3209-18

Since I began to play canoe polo a mere 3 years ago at Bangor University in North Wales, I have continually tried to improve my personal kayaking through work in the gym.  Now having graduated, I am training towards being a Strength and Conditioning coach and I am seeing a growing population of paddlers (polo specifically) who look like monsters when inside their kayak, but when they get out of their boat  their biceps are bigger than their quadriceps! Why is this? Because one of the first things we were taught in a kayak is to press through our feet for a stronger stroke?  An important thing to consider before you continue to read is that to my knowledge there is no research stating that a stronger pushing force with the legs will in fact benefit your kayaking stroke. Also note that I know of no evidence to state that having a weaker pushing force will hinder this performance. The main worry paddlers have is gaining unnecessary weight that they then have to pull through the water. But consider that training to improve (for example) your squat or deadlift (fundamental exercises to all sports for a number of reasons) by 10kg does NOT make you 10kg heavier.  But the important question to ask here is does this extra force give you a stronger stroke? We don’t know yet, but here is what we do know.

As kayakers we are all encouraged towards training from the waist up, and for obvious reasons that I don’t need to explain (see Fekete 1998, Michael et al 2008, Ackland et al 2003). However a study that compared leg girth sizes of elite rowers against kayakers found that rower’s legs were stronger and larger. Although this information is interesting, it is flawed as half the kayaking population for the study were recreational (Sklad at al 1994). Other researchers then use information like this in their own studies to justify the fact that training the legs for kayaking is unimportant.

A good example is from a very well known race kayak manufacturer, giving tips on cross training for flat water racers. They talk about how legs are used to increase torso rotation during the stroke, but likely have enough strength from walking running biking and other activities, and state that leg training is not generally important to improve you’re kayaking, but it can’t hurt to do.

This does however not reflect Stone and colleagues (2002) very well respected work of five criteria that can be applied in order to maximise the transfer of training effect. Two of the important ones to note are to “Accentuate regions of force production” and the “Dynamics of effort”, meaning your leg training for a forwards kayaking stroke should consist of efforts greater than that felt in your kayak and in a similar static motion.

Obviously just like upper body and core training there are other aspects to consider, such as mobility of the muscles in and around the hip (which can be improved with good squat mechanics). You would also expect that application of force and direction changes when you perform every other stroke involved with kayaking and canoe polo such as dipping, double pumping, and throwing. Also consider how individual characteristics can effect these parameters as every kayaker has their own style. Michael & Colleagues (2008) nicely state ” Kayaking is one such sport, where although paddlers possess unique characteristics not commonly observed in the general population, there is no single trait that distinguishes an elite kayak paddler.” However, I digress.

Core muscles are religiously trained in kayaking so that the power output from our upper torso can be transferred to our lower body and to the boat. Because in simple terms a floppy core means that you are losing potential power to drive you through the water, like firing a bow and arrow with a loose string. With this in mind you would expect the legs to work in the same way. Trying to pull your body towards your feet through two tightly coiled springs instead of some soggy spaghetti legs will increase your stroke power.

How many times after a long day boat training have you felt stiff in your legs? And have you also ever tried to perform a seated row (predominantly a upper torso exercise)  in the gym at your maximum weight with straight legs, bent more than 90°, and on one leg? Is there a difference? You tell me.

Also consider the medial angle of your knee  while kayaking, if you sit in this position for a considerable period  of time, on a regular basis because of hip adductor activity, your knee will be encouraged to fold inward when you walk and run. Simply because these muscles will “shorten” if you do not compensate with hip abductor exercises, which occurs with good squatting position.

This is the opinion that I have gained from the evidence that I have seen and my experiences as a kayaker. You should know that I am unbiased in the research that I find, and carefully rethink my opinion after every article, paper and web page I read and video I see. I look forward to the day that these questions can be answered unequivocally so that the science of kayaking can improve and we can all become more efficient in our discipline. But until that day I will continue to enjoy performing squats and deadlifts in the gym as I believe it is making me a stronger kayaker.

Written By Sam Murphy DNA Sports Performance S&C Level 2 Intern 2011-12

Well no doubt even the most dedicated of our athletes let their training and nutrition habits slip over the festive period.  Therefore I though it was a great time to share my thoughts on intermittent fasting as a way of putting on lean mass and losing fat mass.

About a year ago one of my assistants, Adam Bentley, put together a plan for me. At first I though he had gone mad……don’t eat breakfast…..don’t eat small meal regular and often……eat everything within a eight hour window he said ! This was the exact opposite of what I had been doing since my first year of undergrad when I had first researched performance nutrition. But after read around some of his recommendations a bit I though I would give it a go, after all I had nothing to lose and everything to gain !

I’m pleased to say the results surprised me….I lost fat and gained lean mass over a 3 month period, in fact I was 16lbs lighter with clearly more muscle mass and all my strength / power makers were up. What is more, I felt great doing it ! Following on from this I tried it with a some of my athletes and its had great results for them to, the shots below are after four weeks on the program…..

So I hear you say……”How do I apply it with my athletes”…..”What evidence base is there”…..well this PDF, written by Dr John Berardi gives it you all. It a fantastic overview of the subject area and for your reference I was using the 16/8 methodology.

click here for link

It would be great to get your feedback on this once you have applied it with some of your athletes to.

Written By Nicholas Jones DNA Sports Performance Director

Introduction

The sport of running is highly popular with many professional runners through many distances as well as recreational runners looking to maintain/improve fitness as well as those looking to improve their health. However, running comes with its risks with to 52 % of professional and recreational runners suffering with some form of injury whilst running, whether muscular, skeletal or joint injuries (Van Mechelen, 1992.). It is important to understand the risks of running and how to limit these. One trend which has become hugely popular in recent years it that of barefoot running and as such running brands such as Adidas, Puma, Nike and Vibram have developed running shoes that are light-weight and minimalistic in design to mirror the effect of barefoot running whilst reducing the risk of injury sustained from standing on stones, glass and/or other sharp objects found in modern day cities and towns.

Running footwear and performance have long been closely related with a wide variety of research looking at the differences between different shod conditions (Nigg et al, 2003. Verdejo et al, 2004.) as well as differences found between shod and barefoot running (De wit et al, 2000. Squadrone & Gallozzi, 2009. Stacoff et al, 2000.). More recently there has been a large rise in the amount of people taking up barefoot running and this has led to the manufacturing of barefoot simulating products such as the vibram fivefingers model. This running shoe model aims to replicate minimalist running through having an extremely thin sole and minimal support throughout the footwear. It has been suggested that running without any suitable support and cushioning can increase the likelihood of injury, in particular injuries relating to stress such as stress fractures (Giuliani et al 2011).

Barefoot Running, Shod Running and Minimalist running
The use of the term shod running during this article refers to the use of wearing running trainers whilst running. A recent study considered this rise in barefoot running as well as the increase in minimalist running footwear and studied the differences between shod running (SR), barefoot running (BR) (Divert et al 2005; Nigg et al 2000) and running in vibram Fivefingers (VF) (Squadrone and Gallozzi, 2009). This study was able to test the differences between the shod running conditions. The main results relating to the risk of injury found that the impact peak force during the initial contact between the foot and the ground was in fact of significantly lower values during both the BF and the VF conditions when compared against the shod condition (there were no significant differences between the BF and VF impact forces). It has been suggested previously that athletes who had higher vertical force impact peak values resulted in an increased frequency of injury (Hreljac et al, 2000). This therefore, suggests that the risk of injury could be lower in the BF and VF conditions than that of the shod condition. The reasoning behind why these results were found could be drawn from another significant result which was the angle of the ankle which was significantly higher in both the BF and VF conditions compared to that in the shod running condition. This reveals that the foot is in a significantly more plantar flexed position during the BF and VF running condition. This could be due to a number of various reasons such as a reduced contact time (Squadrone & Gallozzi 2009, Nigg et al, 2003,), decreased stride length and even due to the cushioning tendencies of the metatarsals located at the forefoot.

Practical Implications
Therefore with these findings it could be suggested that both BF and VF running could benefit the athlete by reducing the impact forces which could also reduce the risk of injury when compared against shod running. However, alternative research looking at the initial phase switching from shod to BF running suggests that it has related to an increase in injury (Giuliani et al 2011). This suggests that it is a gradual process of the athlete altering his/her stride patterns in order for the athlete to adapt to the differing running technique. Therefore the initial stages of BF or VF running after shod running could be critical to running performance and injury prevention. It has been suggested that specific gait training could reduce the risk of stress injury when transitioning from a shod running condition to that of a BF or VF running condition (Giuliani et al 2011). As mentioned previously the angle of the foot is significantly more plantar flexed during the BF and VF running conditions therefore the gastrocnemius muscles located at the calve have increased tension and this could suggest that there may be an increase in the risk of injury to the muscle due to overuse if this is not monitored closely and adjusted accordingly once any tightness or soreness develops.

Reference:

De Wit B, De Clerq D, Aerts P. Biomechanical analysis of the stance phase during barefoot and shod running. J Biomech 2000; 33: 269-278

Divert C, Mornieux G, Mller S, Baur H, Belli A, Mayer F. Re-evaluation of the influence of shoe on running pattern with new treadmill ergometer. Med Sci Sports Exerc. 2005; 5: 237

Giuliani J, Masini B, Alitz C, Owens B, D. Barefoot-simulating footwear associated with metatarsal stress injury in 2 runners. Orthosupersite.com. 2011; 37:7: e320 – e323.

Hreljac, A., Marshall, R.N., Hume, P.A. Evaluation of lower extremity overuse injury potential in runners. Med Sci Sports Exerc. 2000; 32(9):1635-1641

Nigg BM. Stefanyshyn D, Cole G, Stergiou P, Miller J,. The effect of material characteristics of shoe soles on muscle activation and energy aspects during running. J Biomech. 2003; 36: 569-575

Squadrone R, Gallozzi C. Biomechanical and physiological comparison of barefoot and two shod conditions in experienced barefoot runners. J Sports Med and Phys Fitness 2009; 49: 6-13

Verdejo R, Mills NJ. Heel-shoe interactions and the durability of EVA foam running-shoe midsoles. J biomech 2004; 37: 1379-1386

Van Mechelen W. Running injuries: a review of the epidemiological literature. Sports Med 1992; 14:320-335.

To cool or not to cool…..that is the question !

Introduction

Welcome to this post on the performance benefits that can be gained through the use of external cooling. As all athletes will no doubt have experienced as soon as we start to exercise we start to get warmer and as we get warmer the body starts a number of processes in order to cool us back down and maintain our optimal body temperature of 37 degrees. A critical increase of this body temperature is considered to be the primary factor leading to fatigue and reduced performance in any endurance exercise (Galloway and Maughan, 1997).

Physiology

The body has adapted to help us cope with the demands of increasing body temperature through mechanisms such as vasodilation (expansion of the veins to increase blood flow) which results in sweating and an increase of heat loss through radiation (body heat passing from the body into our surroundings). In order to meet the cooling demands the large increases in blood flow to the skin requires an increased cardiac output (CO) through a raise in heart rate (HR). Skin blood flow and sweating continue to increase in proportion to internal temperature until a steady state is reached at which heat dissipation and heat generation are equal, and therefore body temperature is constant or until maximal responsiveness is reached (Johnson et al., 1984).

Limitations such as these and the body’s ability to adapt to them can make all the difference to the success of a high level athlete. Unfortunately this adaptation to decrease the bodies temperature may also have the effect of diverting oxygen rich blood away from the working muscles and brain reducing the amount of energy we can produce through the aerobic system (Montain & Coyle, 1992) reducing performance (Nielsen et al., 1993) and increasing lactate accumulation (Young et al., 1987).

One theory that suggests a practical application for the control of this response is the use of external cooling to reduce amount of blood pumped to the skin required to maintain a stable body temperature. The suggestion is that the body has an upper limit of temperature control where the amount of heat the body can release is matched by the amount the body produces. Once this maximal temperature has been reached it is well documented that exercise intensities have to be terminated or reduced (Marino, 2002) or risk suffering from some form of heat illness, collapse and in extreme cases even death (Bergh et al., 1979).

One of the mechanisms to control this increase in temperature is the shunting of blood away from the vital organs and towards the skin and working muscles. This process of blood shunting occurs during all forms of exercise however, in the higher intensities commonly found in team sports there is a competition between the muscles and the skin for the blood with the muscles needing the oxygen it carries for muscular contraction and the skin requiring a reduction in body temperature through sweating and radiation. At this point of maximal temperature being reached the brain starts diverting more blood away from the muscles and towards the skin in an effort to reduce the critical body temperature with the side effect of preventing continued muscular contraction through the reduction of the availability of oxygen rich blood (Nielsen et al., 1993). If however the amount of blood sent to the skin was reduced through an external cooling effect more oxygenated blood would be available to be sent to the muscles and allow for the continuation of exercise.

Research

Due to this noticeable decrease in performance a lot of sports science research has gone into looking at ways to limit this reduction in performance through use of pre cooling strategies such as total body immersion in water, the wearing of ice vests or the immersion of the athletes hands in cold water resulting in some supportive findings suggesting that reducing the core body temperature before exercise has the benefit of increased exercise endurance when exercising in warm or up to maximal conditions (Gonzalez-Alonso et al., 1999).

A related study by Hessemer et al. (1984) using cyclists found that pre cooled subjects could achieve a considerably higher rate of absolute work load. Similarly to this, Olshewski and Bruck (1988) were able to increase endurance time from 19 minutes (during control test) to 21 minutes after pre cooling. Duffield and Marino (2007) had similar findings on their test population of rugby players finding in a repeated sprint for distance test that individuals covered a greater distance in a set time with a lower heart rate after sitting in an ice bath for 15 minutes then competing at 31^oC. A slightly different study looking at 5000m running showed that the use of ice vests in the runners warm ups decreased the perceived exertion and heart rate of the runners in the first 3000m run and reduced total running time by on average 13 seconds with a faster pace being evident in the last two thirds of the run when performing at 32^oC (Arngrımsson et al., 2003).

Practical applications

Taking this research into account as well as the availability and expense of using ice vests or cold water immersion techniques pre exercise the recommendations for the average athletes would be not to wear base layers or compression tops as standard when competing. The benefits gained from wearing compression tops are varied and can be beneficial to performance but when offset against the limitations that the increases in heat retention may actually lead to a reduction in performance. This being said this blog is not meant to suggest that a benefit to performance cannot be gained through use of compression clothing and base layers but that judgement should be exercised as to whether or not their use is necessary to keep warm both before and during match play and practice.

As the majority or UK sport is currently played in temperatures sub 15 degrees the body is likely never to reach that maximal threshold of heat production/expulsion and as such thermoregulatory strategies need not be enforced unless extreme levels of exertion are expected to be performed. In competition where temperatures rise above the 20^oC it would be recommended that the most simple and cost effective action in maintaining a stable body temperature would be to drink cold fluids directly before exercise giving the added benefits of reducing the negative effect of water loss on the body as well as preventing excessive temperature increases (Skien & Duffield, 2010).

It should also be noted that possible benefits gained from external cooling should not be taken as advice against completing a warm up prior to exercise and should be avoided completely in short time explosive events such as competitive weight lifting where a reduction in muscular temperatures have been shown to decrease potential muscular power.

Written By Richard Wilcock DNA Sports Performance S&C Intern 2011-12

Bergh U, Ekblom B. (1979). Physical performance and peak aerobic power at different body temperatures. J Appl Physiol, 46, 885–9.

Duffield R. & Marino F.E. (2007). Effects of pre-cooling procedures on intermittent-sprint exercise performance in warm conditions. Eur J Appl Physiol,  100,727–735

Galloway, SDR., and Maughan, RJ. (1997) Effects of ambient temperature on the capacity to perform prolonged exercise in man. Medicine and Science in Sports and Exercise, 29, 1240–1249.

Gonzalez-Alonso, J., Teller, C., Andersen, SL., Jensen, FB., Hyldig, T., and Nielsen B. (1999). Influence of body temperature on the development of fatigue during prolonged exercise in the heat. Journal of Applied Physiology, 86, 1032–1039.

Hessemer, V., Langusch, D., Bruck, K., Bodeker, RH., and Breidenbach T. (1984) Effect of slightly lowered body temperatures on endurance performance in humans. Journal of Applied Physiology, 57, 1731–1737.

Johnson, JM., O’Leary, D., Taylor, WF. and Park, MY, (1984) reflex regulation of sweat rate by skin temperature in exercising humans. Journal of Applied Physiology, 56, 1283-1288.

Marino F. E. (2002) Methods, advantages, and limitations of body cooling for exercise performance. Br J Sports Med, 36, 89–94

Montain, SL., and Coyle, EF. (1992) Fluid ingestion during exercise increases skin blood flow independent of blood volume. Journal of Applied Physiology, 73, 903–910.

Nielsen, B., Hales, JRS., Strange, S., Christensen, NJ., Warberg, J., and Saltin, B.  (1993). Human circulatory and thermoregulatory adaptations with heat acclimation and exercise in a hot, dry environment. Journal of Physiology,  460, 467–485.

Olschewski, H. and Bruck, K. (1998) Thermoregulatory, cardiovascular, and muscular factors related to exercise after precooling. Journal of Applied Physiology, 64, 803–811.

Sigurbjorn A . Arngrımsson, S.A. & Petitt, D.S. (2003). Cooling vest worn during active warm-up improves 5-km run performance in the heat. J Appl Physiol, 96, 1867–1874

Skein M. & Duffield R. (2010). The effects of fluid ingestion on free-paced intermittent-sprint performance and pacing strategies in the heat. Journal of Sports Sciences, 28(3), 299–307

Young, A., Sawka, M. and Epstein, Y. (1987) Cooling different body surfaces during upper and lower body exercises. Journal of Applied Physiology, 63, 1218-1223.

Houglum (2005) describes massage as the systematic and scientific manipulation of soft tissue for remedial or restorative purposes. Massage produces various reflex and mechanical processes on the treated area (Houglum, 2005). Myofascial release (MR) is a form of soft tissue physical therapy used to treat somatic dysfunction and accompanying pain and restriction of motion. Houglum (2005) defines MR as the use of manual contact for evaluation and treatment of soft-tissue restriction and pain with the eventual goal of the relief of those symptoms to improve motion and function. Similarly, Curran et al,. (2008) describes MR as a system of diagnosis, which engages continual palpatory feedback to achieve release of myofascial tissues. This is accomplished by relaxing contracted muscles, increasing circulation, increasing venous and lymphatic drainage, and stimulating the stretch reflex of muscles and overlying fascia.

Arroyo-Morales, et al. (2008) highlight that the value of massage as a recovery method following high-intensity exercise has yet to be established. Myofascial release massage favors the recovery of heart rate variability and diastolic blood pressure after high-intensity exercise (three Wingate tests) to pre-exercise levels, meaning that MR and SMR techniques can be implemented as a recovery aid following training/competition (Arroyo-Morales, et al., 2008).

Benefits of Self Myofascial Release

• Correct muscle imbalances.
• Increase joint range of motion.
• Decrease muscle soreness.
• Decrease neuromuscular hypertonicity.
• Increase extensibility of musculotendinous junction.
• Increase neuromuscular efficiency.
• Maintain normal functional muscular length.
• Relieve joint stress.

SMR Physiology

Autogenic inhibition and the stimulation of the golgi tendon organ (GTO) is the reason as to why self-myofascial release (SMR) using a foam roller or other implement (such as a tennis ball, hockey ball, etc.) is so effective. The GTO is a mechanoreceptor located at the muscle-tendon junction; it’s main function being to regulate the level of tension within the muscle tendon unit.

Autogenic inhibition is the reflex muscle relaxation as the muscle/tendon tension increases to the point of a high risk of injury (e.g. tendon/muscle rupture). The GTO stimulates muscle spindles to relax the muscle in question in order to protect the muscle from injury. During SMR, the muscle contraction that precedes the passive stretch stimulates the GTO, which in turn causes relaxation that facilitates this passive stretch and allows for greater range of motion. With foam rolling, you can simulate this muscle tension, thus causing the GTO to relax the muscle (Robertson, 2008).

Traditional stretching techniques simply cause transient increases in muscle length (assuming that we don’t exceed the “point of no return” on the stress-strain curve, which will lead to unwanted deformities). SMR, on the other hand, offers these benefits and the breakdown of soft-tissue adhesions and scar tissue (Robertson, 2008).

A recent study examined the effects of foam rolling on myofascial release and performance (Healey, et al., 2011). Although the study concluded that thirty seconds of foam rolling on each of the lower limbs and back had no effect on performance, post-foam rolling fatigue measures were significantly less than post-planking fatigue measures. Healey, et al. (2011) suggest that this reduced feeling of fatigue may allow athletes to extend acute training time and volume, therefore resulting in chronic performance enhancement. However, it should be noted that further research is required in order to examine the effects of chronic foam rolling on performance.

Conclusion

Active Release Techniques (ART) or other deep-tissue modalities have long been utilized by individuals in order to eliminate adhesions and scar tissue. Unfortunately, from both a financial and convenience standpoint, we can’t all expect to get ART or massage done on a frequent basis. SMR techniques prove to be a more convenient and financially cheaper method of myofascial release. For specific SMR techniques, head over to our ‘Athlete Zone’, see ‘Roll Your Way To Improved Performance’ article. Please head over to our YouTube channel for our latest video on specific SMR techniques:

You Tube Channel

References and Further Reading
Arroyo-Morales, M., Olea, N., Martinez, M., Moreno-Lorenzo, C., Díaz-Rodríguez, L., and Hidalgo-Lozano, A. (2008). Effects of Myofascial Release After High-Intensity Exercise: A Randomized Clinical Trial. Journal of Manipulative and Physiological Therapeutics, 31 (3), 217-223.

Curran, P.F., Fiore, R.D., and Crisco, J.J. (2008). A Comparison of the Pressure Exerted on Soft Tissue by 2 Myofascial Rollers. Journal of Sport Rehabilitation, 17 (4), 432-442.

Healey, K., Dorfman, L., Riebe, D., Blanpied, P., and Hatfield, D. (2011). The Effects of Foam Rolling on Myofascial Release and Performance. Journal of Strength and Conditioning Research, 25 (), S30-S31.

Houglum, PEGGY A. (2005). Therapeutic Exercise for Musculoskeletal Injuries. Second Ed. Champaign, Il: Human Kinetics, 153-196.

Robertson, MIKE. (2008). Self-Myofascial Release: Purpose, Methods and Techniques. Robertson Training Systems.

Written By Chris Wainer DNA Sports Performance Intern 2010-11

Benefits/Contraindications of SMR

Robertson (2008) suggests a number of reasons as to why you might want to include SMR and foam rolling techniques in your training:

• Improved mobility and range of motion.
• Reduction of scar tissue and adhesions.
• Decreased tone of overactive muscles.
• Improved quality of movement.
• Fill in the gaps between physical therapy and/or deep tissue massage sessions.

There are also several reasons as to why you may not want to include SMR and foam rolling techniques in your training, or areas to avoid (Robertson, 2008):

• Recently injured areas.
• Circulatory problems.
• Chronic pain problems.
• Bony prominences/joints.

General Guidelines

Robertson (2008) recommends that like all training principles, rationalised progression must be implemented in order to elicit continued progression. Area and density can be altered by using different sized and dense implements, e.g. foam rollers, medicine balls, tennis balls…and for the brave ones amongst us, hockey balls!!
Force can also be altered in a number of ways:

• If you have two legs on the foam roller, take one off.
• If possible, stack one leg on top of the other.
• If you have a hand/foot on the ground for stability purposes, take it off (resulting in more of the body’s weight being rolled).

Specific SMR Techniques

Robertson (2008) highlights a number of SMR techniques.
Positioning while on the foam roller is critical for several reasons:

• Improper alignment may stress the supporting muscles and/or joints.
• Improper placement can lead to excessive fatigue of the supporting musculature.
• Improper placement can lead to excessive pressure on the trained area, which decreases compliance.

Duration on SMR and foam rolling techniques varies for several reasons

• The amount of time necessary to get the derived benefits is directly related to your current tissue quality, e.g. poor tissue quality requires more time and attention.
• In contrast, the more familiar you become with the techniques and the easier it becomes, the less time you should need on the roller/ball.
• As a general guideline, you should spend one to two minutes on each area when starting out.
• The key is to spend the most time on the tightest tissues.

Conclusion

SMR on the foam roller offers an effective, inexpensive, and convenient way to both reduce adhesion and scar tissue accumulation, and eliminate what’s already present on a daily basis. Just note that like stretching, foam rolling doesn’t yield marked improvements overnight; you’ll need to be diligent and stick with it – although you’ll definitely notice acute benefits (Robertson, 2008). If you’re interested in the science behind SMR and foam rolling techniques, head over to the ‘Theory Zone’, see ‘Self-Myofascial Release’ article.
Or head over to our YouTube channel for our latest video on specific SMR techniques and get rolling your way to improved performance
You Tube Link

Written By Chris Wainer DNA Sports Performance S&C Intern 2010-11
References and Further Reading
Robertson, MIKE. (2008). Self-Myofascial Release: Purpose, Methods and Techniques. Robertson Training Systems.