The Master Manipulators.

First Blog and reasoning

I have come to share my views and opinions long past the appointed hour of being able to reverse the impending collapse of the current civilisation as we know it. My motivation on this journey is to simply convey information that might help people understand the reasons why we have, as a species arrived at this point and also to help people who survive to adjust and make the most of a new start in the aftermath of this inevitable collapse.

Personal Thoughts

I say current civilisation as there have been many civilisations before this that have inexorably collapsed just like were witnessing today. From my research and putting pieces together, like you would a jigsaw puzzle has allowed me to understand many things. Things I simply would never have recognised or conceived possible had I continued to stay in a very small box of thought the master manipulators of this great planetary body had placed me in.

The Manipulators

I have researched many topics regarding the true rulers of this planet. I was never drawn to any particular theory or disregarded any at the same time. I came to these conclusions based on the fact there was no tangible evidence to nail it down. I decided that if I used the research and applied pragmatism, common sense and an open mind that I should find at least a compass bearing that should send me in a close enough direction to make a formed theory for myself.

Some suggest there are aliens that control humanity, there are suggestions that its even a reptilian race of aliens and has a large following to back it up. From my standpoint do I really believe were the only intelligent species in the solar system that holds more galaxies than there are grains of sand on the planet and that each galaxy has the potential to hold millions of planets that can harbour life, just like our planet. So yes there’s clearly a chance out there that aliens are around and its plausible that a species billions of years old can manipulate humanity based on knowledge and technology. Since I can’t confirm either way I prefer to look at it as a dark malevolent force that hangs over humanity. I say malevolent because it certainly isn’t a benevolent force.

This malevolent force has created a playground for itself called earth and in the playground the children play I.E human beings. This is where things can get complicated but ill try my best to break it down as best I can based on my research and applying pragmatism. Earth isn’t about humans inhabiting a planet and working 40 hours a week or more scratching a living each week till you die. Surely there has to be more to it right?

consciousness/3rd dimension

It appears were not human and in fact were a soul or consciousness. The human body is our spacesuit that allows us to get about on this particular planet. In essence we don’t die we just disconnect from our spacesuit and our consciousness or soul lives on. We are on this planet to learn lessons, to evolve as a consciousness. The objective is to help people without an agenda and in so doing you are a candidate to evolve to higher dimensions as a consciousness. On earth we live in 3rd dimension which means the manipulators of the planet are probably no higher than 4th dimension consciousness. In order to keep their playground and the humans that inhabit the planet the manipulators must stop humans ascending to 4th dimension and beyond. If we all ascended or most then these manipulators lose their playground and their control as we all evolve beyond their playground and their ability to control us with their primitive techniques. It seems consciousness of lower dimension are susceptible to been malevolent in nature and higher dimension consciousness is more pre disposed to benevolent behavior. Clearly from this equation it shows why humans and the planet itself has chosen to live in a dystopia as opposed to a utopia.

The manipulators no humans can be controlled most effectively through fear and stress. Humans or 3rd dimension consciousness in these conditions are most likely to choose the easy route to a solution. You often find examples of this in everyday life and can also relate to this affectively if brutally honest with one’s self.  All the manipulators have to do now is control and set the paradigm they want to induce the particular results that will give them all the control they will ever need.

I assume that’s why we see perpetual war, starvation in a world of plenty, children sleeping on the streets, drugs, the ravaging of our planet for resources and many other things to long to put into a list.

Reincarnation

There is many examples over the years of people who speak of past lives and remember details that are accurate and later proved. Reincarnation plays an important tool for the manipulators in cementing their grip over humanity. For humans we live on average 75 -80 years old and then that’s it or is it?

What if as a consciousness we chose to keep reincarnating on earth so we can learn quicker and more effectively or was even compelled to go back to help break the grip over humanity by the manipulators themselves. Maybe we keep reincarnating on earth because we simply aren’t learning any lessons which is played out in evidence on the planet itself and that we are stuck in 3rd dimension and this planet until we start living by better moral codes and choose to help each other instead of competing and fighting each other.

The above is all speculation and cannot be proved but one thing I do know is true for myself, is from the day I was born I have always had a strong moral code, a want to do good and to help people. These arent qualities ive produced in this lifetime but have already carried over and been cemented in my consciousness for some considerable time proven by an unwavering determination to not let them be destroyed. Along the way these have not always been the easiest things to keep and I’ve been tested whilst seeing others give away there’s so easily and for such a little price. I wonder why I have this and what has compelled me to keep them no matter what and in spite of the planet demanding and coveting these things the most to take from me. Is this evidence of learning from previous lives passed down in information through the DNA of our spacesuits of lives we can’t remember. Are we not supposed to remember our previous lives as a test to see what we have learned and what we bring with us to our new life, to truly see if that has stuck and we are learning as a consciousness. If we remembered it would takeaway from the legitimacy of our actions and would be synthetic as opposed to natural like a person who knows there is a camera on them will always act differently than if they had no knowledge of that fact. Some people say the manipulators tamper with our DNA or shorten our life spans so it slows down our evolution to 4th dimension but although it’s a compelling argument I don’t believe it plays into the wider cosmology of things for it to ring true.

At the end of the day the manipulators and the planet itself can take everything away from you and it will. It’s all been set up that way but their’s only one thing it can’t take and you have to give it up to them and it’s what you stand for, your consciousness, your beliefs, your morals, YOU. When you hear the term they sold their soul to the devil, well that term exists for a reason and has stood the test of time because it’s a true law of this planet. I see and hear the regrets of people who are dying and each time I see it I see their own realisation dawning on them that it’s not so much their dying and their scared or they will miss there loved ones but of the fact that they signed up for a mission to this planet and they have failed that mission, that they never even got started with it and got distracted away from their mission by a planet that was set up to divert and make them fail that mission by design. Of course they don’t remember that mission but they feel it in their subconscious vibrating away at its highest note as they tumble towards their last breath.

Keep to your mission, stay the course and enjoy evolution to 4th dimension or endure a 3rd dimension hell designed to catch fallen souls.

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Plyometrics training for soccer

What is plyometric training
Plyometric training is popular among athletes in dynamic sports such as soccer. Jumping, hopping, skipping and bounding are executed with the aim of increasing dynamic muscular performance. In these exercises muscles undergo rapid elongation followed by an immediate shortening called the stretch shortening cycle. This utilises the elastic energy stored during the stretching phase (Vaczi et al, 2013).

Why is it used in soccer?

ImageMiller et al (2006) highlights that there is a consensus plyometric training is seen to improve sport specific skills such as agility, vertical jump performance and common measures of muscle power. In soccer there is rapid movements like acceleration, deceleration, jumps and changes of direction. A high level of dynamic muscular performance is required at all levels of this training status. According to Chamari et al (2008) plyometric training is effective at improving speed using jumping exercises. Speed cannot be performed without a high rate of power production, the rapid application of force and acceleration. This is why plyometrics is so specific to soccer as it corresponds dynamically with many athletic activities such as jumping, sprinting and kicking and thus can be assigned a high priority in training by the coach.

Stretch shortening cycle

Turner & Jeffreys (2010) describe the stretch shortening cycle as an eccentric phase or stretch followed by an isometric transitional period referred to as the amortization phase, leading into an explosive concentric action. SSC is synonymous with plyometrics and is often referred to as the reversible action of muscles. Examples of SSC actions include running, walking and the winding up movement in throwing.

Kopper et al (2014) suggest that muscles can develop greater force and perform greater work in the concentric phase if prior to the shortening, stretch occur compared to shortening without prior stretch. The greater work can be put down to the muscles elastic energy during lengthening. Counter movement jumps can hightlight the magnitude of lengthening and pre load on muscle performance during the concentric contraction phase. With this jump the centre of mass is accelerating and muscle activation is minimal, while in the second phase of joint flexion the muscle activation increases to stop the vertical momentum. Bobbert & Cassius (2005) point out that aside from the enhanced propulsive force, efficient usage of the SSC also affords the athlete with a reduction in metabolic cost of movement. Economical sprinting can recover approximately 60% of the total mechanical energy. Plyometrics can enhance the athletes use of SSC by understanding the mechanics that are involved. Several mechanisms can be involved such as elastin strain energy, involuntary nervous processes, increased active range of movement and coordination.

A mechanism important in the SSC is elastic energy or sometimes referred to as potential energy and is primarily stored in the tendons. The magnitude of the stored energy theorised to be proportional to the applied force and induced deformation. Elasticity plays an important role in enhancing motor output in sports movements (Hobara et al, 2008).

Tendons

Lichtwark & Wilson (2005) suggest that tendons are considered the key site for energy storage because of their ability to extend and store energy and recoil and release energy. Elastic energy stored in the tendons is the key mechanism underpinning the phenomenon of SSC. It is suggested that the tendon recoil is responsible for both increasing power output and conserving energy during locomotion. As a consequence of the tendons ability to store and release energy a goal of all athlete training should be the optimal transfer of potential energy arising from a pre-stretch being delivered to these structures. The transfer however can only be optimised through the development of muscle stiffness throughout the pre-stretch. Stiffness and compliance are therefore key terminology when explaining the efficiency of SSC and the athletes enhanced power output.

The research

Marques et al (2013) conducted a study involving a six week plyometric training program on strength speed abilities and kicking velocity in youth soccer players. The main finding was that the group using plyometric training enhanced there running and jumping performances significantly over a short period of time while the control group never made any gains. The experimental groups vertical jump results increased by 7.7% whilst the other group had a -1.1% decrease in performance. The muscle power increases showed that adaptations in strength are occurring and are likely to be neural at this stage of development. Another study conducted by Brito et al (2014) showed low volume plyometric training for the lower body was eliciting positive increments in maximal strength and these results were deemed to be surprising. The study related the results to improvements in the neuromuscular function i.e increased neural drive to the agonist muscles, that are likely to occur through plyometric training. It should be noted in these results that in soccer gains in muscular strength should not compromise speed of movement. In fact the ultimate goal of strength training is to increase strength so that acceleration and speed in soccer specific skills such as turning, sprinting and changing direction may be enhanced (Chelly et al, 2009).

Here are some videos showing some of the plyometric drills i used to get specificity for plyometric training within soccer:

This drill mimics stopping in soccer – https://www.youtube.com/watch?v=afxa6DXCLrE

This drill mimics jumping for a header – https://www.youtube.com/watch?v=8X5aLpiTW5Q

This drill mimics a throw in – https://www.youtube.com/watch?v=MR_pntzcYZU

This drill mimics landing and changing direction before sprinting – https://www.youtube.com/watch?v=J8MZUk5NaVc

This drill is just conditioning the core for strength when changing direction – https://www.youtube.com/watch?v=73tOEeGudT0

Here are some useful links to other Plyometric blogs

http://www.judgement-day.co.uk/training-guides/2013/10/what-exactly-is-plyometric-training-a-beginners-guide/#.U2hxHVf0P1U

http://fitnessblogger.net/plyometrics-training/

http://blog.nasm.org/fitness/developing-power-in-everyday-athletes-with-plyometrics/

References

Brito, J., Vasconcellos, F., Oliveira, J., Krustrup, P. & Rebelo, A. (2014) ‘Short-Term Performance Effects of Three Different Low-Volume Strength-Training Programmes in College Male Soccer Players’ Journal of Human Kinetics. 40 (0) pp. 121-128.

Bobbert. MF & Casius, U. (2005) ‘Is the countermovement on jump height due to active state development?’ Med. Sci. Sports Exer. 37 (0) pp. 440-446.

Buller, M. (2013) ‘What exactly is Plyometric training? A beginner’s guide’ Available: http://www.judgement-day.co.uk/training-guides/2013/10/what-exactly-is-plyometric-training-a-beginners-guide/#.U2hxHVf0P1U. [Last accessed 5th may].

Chamari, K., Chaouachi, A., Hambli, M., Kaouech, F., Wisloff, U. & Castagna, C . (2008) ‘The five-jump test for distance as a field test to assess lower-limb explosive power in soccer players’ Strength & Conditioning Journal. 22 (0) pp. 944-950.

Chelly, M.S., Fathloun, M., Cherif, N., Amar, M.B., Tabka, Z. & Praagh, E.V. (2009) ‘Effects of a back squat training program on leg power, jump, and sprint performances in junior soccer players’ Strength & Conditioning Journal. 23 (8) pp. 2241-2249.

De-Ben, L. (2013) ‘Plyometric training’ Available: http://fitnessblogger.net/plyometrics-training/. [Last accessed 5th may].

Hobara, H., Kimura, K., Omuro, K., Gomi, K., Muraoka, T., lso, S. & Kanosue, K. (2008) ‘Determinants of difference in leg stiffness between endurance- and power-trained athletes’ Journal of biomechanics. 41 (0) pp. 506-514.

Kopper, B., Csende, Z., Trzaskoma, L. & Tihanyi, J. (2014). Stretch-shortening cycle characteristics during vertical jumps carried out with small and large range of motion. Journal of Electromyography & Kinesiology. 24 (2), 233-239.

Lichtwark, G.A & Wilson, A.M. (2005) ‘In vivo mechanical properties of the human Achilles tendon during one-legged hoping’ J Exp Biol. 208 (0) pp. 4715-4725.

Marques, M.C., Pereira, A., Reis, I.G. & Van Den Tillar, R. (2013) ‘Does an in-Season 6-Week Combined Sprint and Jump Training Program Improve Strength-Speed Abilities and Kicking Performance in Young Soccer Players?’ Journal of Human Kinetics. 39 (0) pp. 157-166.

Miller, M.G., Herniman, J.J., Richard, M.D., Cheatham, C.C. & Michael, T.J. (2006) ‘The effects of a 6 week plyometric training program on agility’ Journal of Sports Science & Medicine. 5 (0) pp. 459-465.

Nasm. (2013) ‘Developing Power in Everyday Athletes with Plyometrics’ Available: http://blog.nasm.org/fitness/developing-power-in-everyday-athletes-with-plyometrics/. [Last accessed 5th may].

Turner, A., Jeffreys, I. (2010) ‘The Stretch-Shortening Cycle: Proposed Mechanisms and Methods for Enhancement’ Strength & Conditioning Journal. 32 (4) pp. 87-99.

Vazci, M., Tollar, J., Meszler, B., Juhasz, I. & Karsai, I. (2013) ‘Short-Term High Intensity Plyometric Training Program Improves Strength, Power and Agility in Male Soccer Players’ Journal of Human Kinetics. 36 (0) pp. 17-26.

 

 

 

Complex training for soccer

So what is complex training?

The traditional method for training strength is to initially develop muscle hypertrophy and strength in preparation for the transition phase to power and maximal strength. However a new method of training integrates both strength and power during training sessions and is called complex training (Duthie et al, 2002).

ImageRobbins (2005) explains that complex training is a workout comprising of resistance training followed by a matched plyometric exercise with movement patterns as close to soccer skills aiming to get the highest degree of transference between strength gains and soccer technical skills. The rational for this method is the theory of post-activation potentiation of the neuromuscular system which is a phenomenon induced by a voluntary conditioning contraction performed at maximal or near maximal intensity. This in turn can create an increase in peak force and rate of force development during subsequent twitch contractions.

The use of complex training in soccer

In soccer many studies have shown using weightlifting results in significant improvements in match related physical abilities. Brito et al (2014) suggests however since soccer is a team based sport most training is dedicated to field based conditioning drills to ensure player preparedness. This presents a problem incorporating strength training. This is where the coach needs to rationalise the time given to make sure players get the correct prescribed amounts of strength training necessary. Los Arcos et al (2014) highlighted from a study that the use of complex training on soccer players over a short period of time managed to induce positive adaptations in the performance of horizontal and vertical jumps and improving athlete performance during competition. This shows the benefits the coach can potentially achieve from using complex training.

PAP)

Sale (2002) suggests that contracting muscle is determined by its contracting history. Repetitive contractions leads to fatigue, at the same time however post activation potentiation or (PAP) is elicited. This is where acute muscle force output is enhanced as a result of contractile history. Chiu et al (2003) postulates that explosive movements can be enhanced if they are preceded by a bout of heavy resistance exercise. The performing of a set of high intensity squats prior to horizontal jumps enhances the performance as the neuromuscular system gets excited creating contractile activity. PAP and fatigue can occur at the same time, they can also co-exist during increased muscle contraction activity and when gradually returning to original levels.

Here are some example videos i did showing heavy resistance sets before a standing jump and a triple jump.

Squat reps – https://www.youtube.com/watch?v=LpA6LVCv_eo

Standing jump – https://www.youtube.com/watch?v=HASsiVCupuM

Alternate squats – https://www.youtube.com/watch?v=LYcxgQ38Tz8

Triple jump – https://www.youtube.com/watch?v=AMlN6KhU-gc

I did 4 reps at 40kg i know not a very heavy resistance but for someone like me who doesn’t work there legs and has lousy technique this was pretty hard going. In my first standing jump pre heavy resistance i scored 2.10m distance. After heavy resistance i scored a jump of 2.14m. PAP is possibly occurring here although only a minimal gain. Pre heavy resistance squats for the triple jump i scored a distance of 8.47m. After heavy resistance squats i jumped to 8.75m. Again some more evidence to suggest that the PAP phenomenon is a live variable. To put some meat on the bone of the findings that was made, i had a look at some results from other studies that looked into using heavy resistance training. Alves et al (2010) conducted a study loading participant’s neuromuscular systems with maximal intensitys of 3-5 reps on leg press contractions. Shortly after the athletes began performing 8 vertical counter movement jumps. The mean of the 8 jumps were calculated and the results showed that the athletes jumped on average 3.3% higher after pre loading with maximal intensities than they did before any loading took place. Another study conducted by Chelly et al (2009) had an emphasis on pre and post loading of maximal intensities to see the effects on vertical jump performance. The athletes performed 5RM back squats pre and post vertical jumps. The results showed again that pre loading had a positive influence on vertical jump performance but on post loading the results showed a 2.8% increase in jump performance on even the pre loading maximal intensities.

Conclusion

Their is evidence provided that PAP does indeed exist Tillin & Bishop (2009) showed from a study examining skeletal muscle fibres, they observed twitch potentiation in skinned fibres and concluded that potentiation was a result of increased myosin light chain phosphorylation. The study also examined the twitch contractile properties of muscle and consistently found increased twitch tension, increased rate of tension development and decreased post stimulus relaxation time. However there are studies that have ellicited no gains from using (PAP). Hrysomallis & Kidgell (2001) conducted a study to investigate the effects of (PAP) in the upper body. Performance was measured using explosive pushups and a set of 5RM bench press was performed prior to the pushups. The results of this test showed no improvents in performance and this was put down to different requirements needed in the upper body in contrast to lower body to ellicit (PAP). A study by Jensen & Ebben (2003) attempted to examine enhancements in peformance of loaded jump squats using 3 sets of 3RM half squats for pre maximal intensity. The results again showed no enhancement in performance even though this was concentrated in the lower half of the body. My final view on this is that (PAP) using complex training can be seen to enhance performance in power and strength techniques for soccer but it may also be inconsistant in results especially across something as broad as a team sport.

Here are some useful links about complex training:

http://blog.voltathletics.com/home/2013/12/3/break-a-mental-sweat-complex-training-for-increased-power

http://www.endurancecorner.com/node/356

https://jcissik.wordpress.com/tag/complex-training/

References

Alves, J., Rebelo, A.N., Abrantes, C. & Sampaio, J. (2010) ‘Short-term effects of complex and contrast training in soccer players’ vertical jump, sprint, and agility abilities’ Journal of Strength & Conditioning Research . 24 (4) pp. 936-941.

Brito, J., Vasconcellos, F., Oliveira, J., Krustrup, P. & Rebelo, A. (2014) ‘Short-Term Performance Effects of Three Different Low-Volume Strength-Training Programmes in College Male Soccer Players’ Journal of Human Kinetics. 40 (0) pp. 121-128.

Chelly, M.S., Fathloun, M., Cherif, N., Amar, M.B., Tabka, Z. & Praagh, E.V. (2009) ‘Effects of a back squat training program on leg power, jump, and sprint performances in junior soccer players’ Strength & Conditioning Journal. 23 (8) pp. 2241-2249.

Chiu, L.Z.F., Fry. A.C., Weiss, L.W., Schilling, B.K., Brown, L.E. & Smith, S.L. (2003) ‘Postactivation potentiation responses in athletic and recreationally trained individuals’ Strength & Conditioning Journal. 17 (0) pp. 671-677.

Cissik, J. (2011) ‘Postactivation Potentiation, Squat Strength, and Adolescent Sprinting Performance’ Available: https://jcissik.wordpress.com/tag/complex-training/. [Last accessed 5th may].

Couzen, A. (2014) ‘Complex Training: The principle of variety and multilateral development’ Available: http://www.endurancecorner.com/node/356. [Last accessed 5th may].

Derwin, J. (2013) ‘Break a mental sweat: complex training for increased power’ Available: http://blog.voltathletics.com/home/2013/12/3/break-a-mental-sweat-complex-training-for-increased-power. [Last accessed 5th may].

Duthie, G.M., Young, W.B. & Aitken, D.A. (2002) ‘the acute effects of heavy loads on jump squat performance: and evaluation of the complex and contrast methods of power development’ Journal of Strength and Conditioning Research. 16 (0) pp. 530-538.

Hrysomallis, C. & Kidgell, D. (2001) ‘Effect of heavy dynamic resistive exercise on acute upper-body power’ Strength & Conditioning Journal. 15 (0) pp. 426-430.

Jensen, R.L. & Ebben, W.P. (2003) ‘Analysis of complex training rest interval effect on vertical jump performance’ Strength & Conditioning Journal. 17 (0) pp. 345-349.

Los Arcos, A., Yanci, J., Mendiguchia, J., Salinero, J.J., Brughelli, M. & Castagna, C. (2014) ‘Short-Term Training Effects of Vertically and Horizontally Oriented Exercises on Neuromuscular Performance in Professional Soccer Players’ International Journal of Sports Physiology & Performance. 9 (3) pp. 480-488.

Robbins, D.W. (2005) ‘Postactivation potentiation and its practical applicability: a brief review’ Journal of Strength and Conditioning Research. 19 (2) pp. 453-458.

Sale, D.G. (2002) ‘Postactivation potentiation : Role in human performance’ Exercise sports science review. 30 (3) pp. 138-143.

Tillen, N.A. & Bishop, D. (2009) ‘Factors modulating postactivation potentiation and its effect on performance of subsequent explosive activities’ Sports Medicine. 39 (2) pp. 147-166.

 

Can Olympic lifting be effective in a soccer player training regimen?

Olympic lifting   

ImageOlympic lifting and power lifting are the most popular training methods used by coaches because of there focus towards power and strength development. Olympic style weightlifting consists of two different lifting techniques –

  1. Clean and Jerk
  2. The snatch

The most important aspect to olympic lifting in focus towards athlete performance is power specific force development or speed strength. Olympic style training involves lifting heavy loads that are performed at a high velocity resulting in high power output (Johnson Jr et al, 2008). Speed strength combines two crucial attributes of athletic performance to bring about power development. An athletes power capacity includes maximum strength, high load speed strength, low load speed strength, rate of force development, reactive strength, skill performance and power endurance. Athletes who use Olympic lifts can increase their speed strength. This is done because during the pull phase of the clean and snatch and the drive phase of the jerk athletes extend their hips, knees and ankle joints to push against the ground as rapidly as possible to producing acceleration on the body and barbell (Hoffman et al, 2004). Using Olympic lifts for training in soccer could be useful for developing strength speed to jump for headers, hold up the ball and quickly stop and change direction. Hori & Stone (2004) suggest that functional core strength is also developed due to the large amounts of overhead activity and movements with high loads away from the body. Different sports require different demands, so for soccer the question that maybe asked in Olympic lifting is how fast rather than how heavy.

Specificity to soccer

Its hard to imagine Olympic lifting having any specificity with regards to soccer as both are completely different from an athletic and aesthetic point of view. Soccer is a team based sport whilst Olympic lifting is an individual event, soccer is an invasion sport that requires lots of movement whilst Olympic lifting is essentially a static event. So how can Olympic lifting be incorporated into soccer training and be specific? Zatsiorsky & Kraemer (2006) suggest that all sports require different types of muscle synchronization, balance, flexibility, coordination as well as strength, speed and power. Olympic lifting can provide developments in all these areas which makes this training specific to soccer. Training maximal strength can impede speed in soccer as the hypertrophic adaptations will lead to decreased flexibility in the joints and movement speed of the muscles during explosive effort. However a way to counter this is to use smaller weights but at higher speeds as strengths gains can still occur. Mcguigan et al (2012) highlight that strength gains from high speed training can induce positive adaptations due to an increase in the number of fibres recruited along with a more effective firing of the motor neurons. In sports requiring short bursts of explosive energy Olympic lifting incorporates the necessary ingredients to accommodate the production of power and as such lead to improved performance in competition.

According to Kipp et al (2010) Olympic lifting is the gold standard when it comes to training athletes in strength and power. The speed of the movements coupled with the multiple movements you find in clean and jerk and the snatch simulate the movements involved in other sports more accurately than any other type of explosive approach. The higher power output created by faster velocity lifting can have a greater impact on positive athletic performance.

Training for improved athletic performance

The main focus of incorporating Olympic lifting in soccer is to help prevent injury. When looking to improve athletic performance power output, muscle synchronization, metabolic and biomechanical specificity are high on the agenda. If there is a set focus through a particular session for example concentrating on vertical jumping in soccer, than cleans and snatches would be used. Another way of training could be to focus on the energy systems used in soccer were explosive movement is required every 30 – 45 second on average and the training could be made specific to the interval and activity demand of this sport. Maximal strength can lead to greater power output so using Olympic style back squats and front squats could be ideal (Chiu, 2007).

Here is a few videos of me demonstrating techniques of Olympic lifts that can be used in soccer training. I decided against using weights for safety reasons as i was a beginner and the lifts are technical:

Safety concerns

As Olympic lifts are very explosive and complex there is always the risk of injury and this is a potential drawback to incorporating this training within soccer. The lifts are very technical and require a lot of coaching and a small error in technique could lead to serious injury due to the weights involved and potential body positions (Mckown, 2007).

This blog highlights the potential dangers and pitfalls of Olympic lifting

http://wilfleming.com/

Here is a list of some useful links to build on Olympic lifting in sport

http://www.olympicweightliftingguru.com/blog/

http://wilfleming.com/eric-cressey-snatch/

http://70sbig.com/blog/2012/07/transitioning-to-olympic-weightlifting/

References

Chiu, L.Z.F. (2007) ‘Powerlifting Versus Weightlifting for Athletic Performance’ Strength & Conditioning Journal. 29 (5) pp. 55-57.

Chiu, T. (2014) ‘Make success routine. Available: http://www.olympicweightliftingguru.com/blog/. [Last accessed 4th may 2014].

Cressey, E. (2013) ‘Earning the Right to train Overhead: Eric Cressey on the snatch’ Available: http://wilfleming.com/eric-cressey-snatch/. [Last accessed 4th may 2014].

Fleming, W. (2013) ‘How to miss Olympic lifts’ Available: http://wilfleming.com/.%5B Last accessed 4th may 2014].

Hoffman, J.R., Cooper, J., Wendell, M. & Kang, J. (2004) ‘Comparison of Olympic vs. Traditional Power Lifting Training Programs in Football Players’ Journal of Strength and Conditioning Research. 18 (1) pp. 129-135.

Hori, N. & Stone, M.H. (2004) ‘Weightlifting Exercises Enhance Athletic Performance That Requires High-Load Speed Strength’ Strength & Conditioning Journal. 27 (4) pp. 50-55.

Johnson Jr, J.B., Sabatini, L.P. & Sparkman Jr, R.M. (2008) ‘A Debate between Power Lifting and Olympic Lifting as the Main Athletic Training Method’ Virginia Journal. 29 (4) pp. 19-23.

Justin. (2012) ‘Transitioning to Olympic weightlifting’ Available: http://70sbig.com/blog/2012/07/transitioning-to-olympic-weightlifting/. [Last accessed 4th may 2014].

Kipp, K., Redden, J., Sabick, M. & Harris, C. (2010) ‘Kinematic and kinetic patterns in Olympic weightlifting’ International Symposium on Biomechanics in Sports: Conference Proceedings Archive. 28 (0) pp. 1-4.

Mcguigan, M.R., Wright, G.A. & Fleck, S.J. (2012) ‘Strength Training for Athletes: Does It Really Help Sports Performance?’ International Journal of Sports Physiology & Performance . 7 (1) pp. 2-4.

McKown, N. (2007) ‘Complete Body Development With Dumbbells’ 2nd Ed. Oxford, UK: Meyer & Meyer Sport.

Zatsiorsky, V.M. & Kraemer, W.J (2006) ‘Science and Practice of Strength Training’ 2nd ed. Champaign, Il: Human Kinetics.

Olympic lifting, power lifting, soccer

 

 

 

 

Using small sided games to develop metabolic conditioning in soccer.

Im using this blog to discuss the methods i have undertaken to get better metabolic conditioning from my athletes so they can perform better and more efficiently during soccer matches.

Why Metabolic conditioning?

Metabolic conditioning of individual athletes in team sports is extremely important. It can define and control the athletes contribution within a game setting. An athletes ability to maintain bursts of high intensity exertion is often the crucial factor in winning and losing soccer matches. Examples of this can be leading a counter attack or keeping up with play. Alternatively without good metabolic conditioning athletes can miss tackles, struggle to get over and block shots or be unable to keep up with play (Gamble, 2007). The Level of fitness is also a critical factor in the athletes ability to fulfil there positional role. It is recognised that sport specific conditioning modes that replicate and overload physiological and kinematic conditions during sporting activity are far more effective for preparing athletes for competition. The aim is to identify the correct amount of stress that will be encountered in a live game situation (Helgerud et al 2001).

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Small sided games

In order to work on the athletes metabolic conditioning i have chosen to use small sided games rather than high intensity interval training.Hoffman Jr et al (2014) suggest that small sided games are becoming ever increasingly popular especially in soccer. SSG’s are basically high intensity games that can be specific or non specific to the sport. It can focus on some aspects the coach is looking to improve. The reason for the application of SSG’s is their ability to replicate game like scenarios in physiological, technical and tactical demands. SSG’s have similarities with high intensity training or HIT because they will use brief bouts of high intensity movement followed by a predetermined period of rest. Ade et al (2014) highlight that heart rate response and blood lactate are most often measured to gain rates of perceived exertion and that these responses are often very similar to soccer match components. This information allows the coach to make a drill easier or harder based on the goals set. SSGs are far better than traditional drills as they can mimic game like scenarios but also produce the correct stress on the athlete that would happen in competition. SSG’s can give the athletes more touches during training that can help with technical or tactical deficiencies.

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Here are some videos of the small sided games we used for metabolic conditioning:

Metabolic demands

What you recognise during soccer is there are bouts of high intensity followed by lower intensity periods meaning its quite intermittent. This means that metabolic conditioning is providing energy for the high intensity work and then replenishing its stores of energy during lower intensities. A key aspect to focus on during metabolic conditioning is the anaerobic system because you want the players to be able to sustain power output and sprint performance for the duration of matches. To perform intermittent maximal energy bursts, the athletes need to recover and systems such as lactate handling, acid/base buffering, PCr and ATP will facilitate this process (Duthie et al, 2003). The aerobic system appears to be the less important system in team sports as studies have shown lower aerobic power output scores during soccer. However repeated sprint exercises have shown to contribute to energy production and this in turn offsets losses in power output from reduced capacity of anaerobic energy production. It has been shown that in order for adaptations to occur in these systems that training beyond their current capacity using intermittent bouts of high intensity followed by passive rest periods yields the best results (Tschakert & Hofman, 2013).

Metabolic adaptations

During the small sided games we performed, a concerted effort was made to give the athletes rest intervals as they wouldn’t be able to keep up with physical demands. Buchheit & Laursen (2013) suggest that anaerobic and aerobic systems are taxed differently dependant on the length of sprints and recovery periods. These interventions have to be accurate to allow adaptations to the systems whilst at the same time avoiding the accumulation of lactate that would compromise work output. Running velocity can develop the blood lactate threshold as improvements are made in lactate handling such as capillirisation of muscle fibres and upgrading of lactate transporters.

Here is an example video of us using high intensity sprints. After a bout, bibs were given to the rested players and the other players took a rest:

Billat et al (2003) points out that a relationship has been found between oxidative capacity of muscle and an ability to resynthesize phosphocreatine or PCr. As such cardio fitness has been shown to improve team sport athletes. Increases in aerobic power, lactate threshold and running economy have been observed in studies. Significant increases were observed in distances covered during games and the frequency of sprints and general involvement in soccer matches were significantly higher.

Here are some useful links regarding metabolic conditioning.

http://www.coachdos.com/74/soccer-is-an-aerobic-sport-isnt-it/

http://www.crossfitnorwest.com/metabolic-conditioning-or-cardio.html

http://www.ihpfit.com/ask-an-ihp-trainer/email-jc/specificmetabolicconditioning.html

http://info.precisionathletics.ca/blog/?Tag=soccer+conditioning+vancouver

References

Ade, J.D., Harley, J.A. & Bradley, P.S. (2014) ‘Physiological Response, Time-Motion Characteristics, and Reproducibility of Various Speed-Endurance Drills in Elite Youth Soccer Players: Small-Sided Games Versus Generic Running’ International Journal of Sports Physiology & Performance. 9 (3) pp. 471-479.

Billat, V.L., Sirvent, P., Py, G., Koralsztein, J.P. & Mercer, J . (2003). The concept of maximal lactate steady state. Sports Medicine. 33 (0), 407-426.

Boyd, C. (2011) ‘Sport Specific Conditioning for Vancouver’s Fall Sports’ Available: http://info.precisionathletics.ca/blog/?Tag=soccer+conditioning+vancouver. [Last accessed 4th may 2014].

Buchheit, M. & Laursen, P. (2013) ‘High-Intensity Interval Training, Solutions to the Programming Puzzle’ Sports Medicine. 43 (5) pp. 313-338.

CrossfitNorthwest. (2013) ‘Metabolic conditioning or cardio’ Available: http://www.crossfitnorwest.com/metabolic-conditioning-or-cardio.html. [Last accessed 4th may 2014].

CoachDosWork.com. (2010) ‘Soccer is an aerobic sport isn’t it?’ Available: http://www.coachdos.com/74/soccer-is-an-aerobic-sport-isnt-it/. [Last accessed 4th may 2014].

Duthie, G., Pyne, D. & Hooper, S. (2003) ‘Applied physiology and game analysis of rugby union’ Sports Medicine. 33 (0) pp. 973-991.

Gamble, P. (2007) ‘Challenges and Game-Related Solutions to Metabolic Conditioning for Team Sports’ Strength & Conditioning Journal. 29 (4) pp. 60-65.

Helgerud, J., Engen, L.C., Wisloff, U. & Hoff, J. (2001) ‘Aerobic endurance training improves soccer performance’ Med. Sci. Sports Exer. 33 (0) pp. 1925-1931.

Hoffman Jr, J.J., Reed, J.P., Leiting, K., Chieh-Ying, C. & Stone, M.H. (2014) ‘Repeated Sprints, High Intensity Interval Training, Small Sided Games: Theory and Application to Field Sports’ International Journal of Sports Physiology & Performance. 9 (2) pp. 352-357.

Santana, J.C. (2012) ‘Specific Metabolic Conditioning’ Available: http://www.ihpfit.com/ask-an-ihp-trainer/email-jc/specificmetabolicconditioning.html. [Last accessed 4th may 2014].

Tschakert, G. & Hofman, P. (2013) ‘High-Intensity Intermittent Exercise: Methodological and Physiological Aspects’ International Journal of Sports Physiology & Performance. 8 (6) pp. 600-610.

 

 

 

Bolivia 6-1 Argentina: The shocking effects of altitude training.

Is this a joke?

On april 1st 2009 a Bolivian soccer team ranked 56th in the FIFA world rankings systematically destroyed an Argentinian team ranked 50 places above them and possessing arguably the greatest soccer player in the games rich history. Looking at the date you would brush this off as no more than a cheap April fools joke. If you heard one you have heard a thousand. Unfortunately for Diego Maradona this was no light hearted tall tale, just an unadulterated hard fact. The then manager said “he felt all the Bolivia goals like knife wounds in his heart”.

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Here is a BBC blog that touches on the events that took place that day and the possible reasons for such an outlandish score line.

http://www.bbc.co.uk/blogs/legacy/timvickery/2009/04/coping_with_high_altitude.html

To fully understand the reasons behind one of the most surprising and shocking soccer results of the modern era i will be focusing on altitude training and its effects on athlete performance.

Altitude

Sporting performances have always been better at altitude. It may be kicking a ball further in Bolivia, longer jumping in Mexico or faster cycling in the Alps. The thinner air at altitude means there is less air resistance and makes these things possible. However it does mean there is less oxygen and in turn this creates various physiological effects on the body (Epthorp, 2014).

Saunders et al (2009) suggests that the continuum of altitude is classified as near sear level (0-500m), low is (>500-2000m), moderate is (>2000-3000m), high is (>3000-5500m) and extreme altitude is (>5500) upwards. The soccer match was played at 4100m above sea level in the Bolivian capital of La Paz and is known as the highest national capital in the world. This match fell into the bracket of high altitude. The percentage of oxygen breathed in, is a constant at all altitudes the percentage is 20.9% but the fall in atmospheric pressure at higher altitudes decreases the partial pressure and changes the gas exchange in the lungs. This results in each breath containing less oxygen and is commonly known as hypoxic conditions.

Physical effects on the body

Paralikar & Paralikar (2010) highlight the effects on the body at varying heights of altitude and show what sort of changes the Argentinian players would have encountered.

High altitude 1500-3500m:

  • Physiological effects through diminished oxygen pressure include decreased exercise performance and increased ventilation.
  • Minor impairment of arterial oxygen transport.
  • Ascending from high altitude quickly can bring about the onset of altitude sickness.

Very high altitude 3500-5500:

  • Extreme hypoxemia may occur during exercise, during sleep or in the presence of high altitude pulmonary oedema.
  • Severe altitude sickness occurs in this range.

Altitude/Hypoxic training

LH + TH method

The original idea of hypoxic training was for the athletes to live and train at moderate altitude for the purpose of increasing erythrocyte volume and ultimately enhancing sea level maximal oxygen uptake (vo2 max) and endurance performance. A conclusion from scientific evidence was that athletes who lived high and trained high wasn’t able to train with the same intensity as there sea level counterparts. Many athletes reported that they lost fitness, form and turnover as a result. Another study showed in 1 and 2 mile runs that performance went down by between 3% and 8% when athletes came back down to sea level to train after LH + TH methods. This could explain why the Bolivian national team cannot take the results they acquire at home and reproduce them away. Most of their players live and train in Bolivia meaning that LH + TH methods are inherent. The results from the studies show that this method of training is not transferable to sea level and that there advantage over the opposition is due to acclimatisation to their high altitude environment (Wilber, 2011).

LH + TL method

A new training method was developed by Levine (2002) in order to counter the sea level decrements in performance. The hypothesis was that LH + TL can have the athletes simultaneously experience benefits of hypoxic acclimatisation along with the maintenance of sea level training intensity. This would then result in positive haematological, metabolic and neuromuscular adaptations. Werlhn (2006) conducted a study to test this hypothesis. a Swiss national team was exposed to LH + TL over a 24 day period. Another group wasn’t exposed to altitude over this period. The results showed a 5% volume increase in erythrocyte, erythropoietic markers and haemaglobin mass, treadmill tests run over 5000m showed 4% increases in (Vo2 max)  and time trials elicited 2% increases in (Vo2 max) in comparison to the group not exposed to altitude.

So what could the Argentine team do to alleviate some of the disadvantages they encountered during the game?

As the club seasons are busy in Europe most players are contracted to national teams for only a few days eliminating the chance to come for 3 weeks to properly acclimatise to their environment. This renders the LH + TH and the LH + TL methods of training irrelevant. There is however another training route that can be taken to offer a little support in increasing performance levels for that game.

LL + TH

The introduction of new hypobaric technologies into the market such as altitude training masks and oxygen tents allows the athletes to live at sea level but be exposed to (IHE) or intermittent hypoxic exposure from between 5 – 180 minutes a day whilst in a resting state. Millet et al (2010) suggests IHT or intermittent hypoxic training can be used over a number of sessions with the aim to induce improvements in performance at sea level and for preparation for competition at altitude. Billaut et al (2012) highlight that IHT can play an important role in creating adaptations on a molecular level in skeletal tissue. These varied adaptations can increase haemoglobin mass and better ventilatory economy. In studies IHT has been shown over a 6 week period to induce enhancement in the glycolytic system creating better transport of enzymes, glucose and PH regulation. However further studies on anaerobic performance concentrating on mean power output using cycling and sprint tests at altitude showed that a placebo group performed as well as the IHT exposed group during testing. Furthermore Mclean et al (2013) suggests that although erythropoiesis is an important adaptation in altitude training such as increasing muscle buffering capacity it cannot be completely accountable for increases in performance and that findings have yet to suggest what the mechanism is for this adaptation. Other studies have even proposed the idea that intramuscular carnosine is responsible for muscle buffering capacity.

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Here is a video showing the use of an altitude mask during sports training:

Final say

The literature supports the ideas that altitude training has benefits mostly when LH + TL because athletes cant produce the same intensities in training and competition at sea level when LH + TH. It has shown that competition at altitude were you may be under prepared is almost impossible to compete with, if the opponent is acclimatised. However there is some hope that using IHT training can compensate and reduce that gap. Breaking down the information during this blog possibly shows that Argentina was on a hiding to nothing and such an anomaly was inevitable at some stage. FIFA recently changed laws to cap matches been played no higher than 2000m above sea level. This backs up the notion of an impossible situation. There is however limitations to altitude training such as accessibility and cost effectiveness of training hypoxic ally. Travel costs especially if its a team sport and time constraints play a major role. Oxygen tents and hypobaric chambers are an option against these barriers but again accessibility and cost are a problem along with theories based on studies that dont show conclusively the benefits to using IHT for acclimatisation purposes (Garvican et al, 2013).

References
Billaut, F, Gore, C.J. & Aughey, R.J. (2012) ‘Enhancing Team-Sport Athlete Performance: Is Altitude Training relevant? ‘ Sports medicine . 40 (9) pp. 751-767.
Epthorp, J.A. (2014) ‘Altitude training and its effects on performance- systematic review’ Journal of Australian Strength & Conditioning. 22 (1) pp. 78-88.
Garvican, L., Saunders, P. & Telford, R. (2013) ‘Altitude Training. Modern Athlete & Coach’ 51 (1) pp. 37-42.
Levine, B.D. (2002) ‘Intermittent hypoxic training: Fact and fancy’ High Alt Med Biol. 3 (0) pp. 177-193.

McLean, B.D., Buttifant, D., Gore, C.J., White, K., Liess, C. & Kemp, J. (2013) ‘Physiological and performance responses to a preseason altitude-training camp in elite team-sport athletes’ International Journal of sports physiology and performance. 8 pp. 391-399.
MercadoTuningPeru.com. (2013) ‘Training mask 2.0 Peru multi sport high altitude training’ Available: http://www.youtube.com/watch?v=lETenvtaJBI. [Last accessed 3rd may 2014].
Millet, P.G., Roels, B., Schmitt, L & Richalet, J.P. (2010) ‘Combining Hypoxic Methods for Peak Performance’ Sports Medicine . 40 (1) pp. 1-25.
Paralikar, S. & Paralikar, J. (2010) ‘High – altitude medicine’ Indian Journal of Occupational & Environmental Medicine. 114 (1) pp. 6-12.
Saunders, P., Pyne, D. & Gore, C. (2009) ‘Endurance Training at Altitude’ High Altitude Medicine & Biology. 10 (2) pp. 135-148.
Vickery, T. (2009) ‘Coping with high altitude’ Available: http://www.bbc.co.uk/blogs/legacy/timvickery/2009/04/coping_with_high_altitude.html. [Last accessed 3rd may 2014].
Werlhn, J.P., Zuest, P., Hallen, J. & Marti, B. (2006) ‘live high – train low for 24 days increases haemoglobin mass and red cell volume in elite endurance athletes’ J Appl Physiol. 100 (0) pp. 1938-1945.
Wilber, R.L. (2011). Application of altitude/hypoxic training by elite athletes. Journal of Human Sport and Exercise. 6 (2), 271-286.

 

 

 

 

 

 

The use of GPS technology in sport

The sports environment has become so competitive in the modern era that technology in sport is playing a far more prevalent role. The margins between victory and defeat are so tiny that athletes and coaches are constantly on the lookout for anything that can give them the sporting edge over the opposition.

The introduction of GPS or the global positioning system is one such technology that is been utilised in the sports industry in an attempt to gain that edge in competition performance. GPS is seen to be used for maximising athletic performance whilst minimising injuries.

Brief History of GPS

The invention of GPS systems are in large thanks to the work performed by Isidor Rabi in 1944. The development of nuclear magnetic resonance methods lead to the creation of atomic clocks. The precise timing from the atomic clocks allowed the basis of satellite navigation. The first attempted inception of a human locomotion device came in 1997 trialled by Garmin, it was however hardly a raw ring success. The first commercially available GPS device became available for sporting application in 2003 and this system was initially validated by a computerised system. Further validation of this system came in 2009 from three studies utilising slightly different methodology. This recent validation testing has allowed for GPS to have a niche in an ever evolving sports market (Aughey, 2011).

Data trackers

Kurzawa (2008) highlights that there are three types of GPS trackers.

  1. The fImageirst is a data logger and it simply records the data at regular intervals on the internal memory of the unit. From there it can be downloaded on to a computer for further data analysis. Data loggers are seen to be the most suitable for people playing sport and can be attached to the athlete throughout. These units collect data on movement patterns speed and distance.
  2. Data pushers send the position of the unit to a server at regular intervals which can instantly update and analyse location, direction, speed and distance. In sport data pushers can be implemented to determine if an athlete is cheating by taking short cuts or determining the gap between competitors.
  3. Data pullers are always on an can be used for location purposes at all times. These devices are becoming more popular all the time within GPS technology.

Benefits of GPS

The use of GPS in field sports can be varied. Cummins et al (2013) suggests that GPS has extensively been used in team sports such as rugby league, rugby union, cricket, hockey and soccer. GPS can be used to objectively quantify levels of exertion and physical stress on the athletes. Other advantages this system provides are that it can examine competition performances, assess different positional workloads, establish training intensities and monitor changes in players physiological demands. A study conducted by Gabbett (2010) focused on physiological demands in competition compared to game based training activities such as small sided games. GPS at 5 Hz was used to record movement of the athletes. The results of the study showed that over 19 training sessions and 32 hockey games the intensity of the 14 female athletes was much higher in competition and that training couldnt replicate what they encountered in competition.Image

 

 

The use of GPS can also contribute to decrease the chances of athletes getting injured or aid in a quicker recovery from injury. Reid et al (2013) suggests that rugby is a very demanding sport physically, requiring a variety of open and closed skills whilst at the same time having minimal breaks in play. Each position requires a different workload and using a GPS monitoring device during training can fine tune sessions were athletes of all positions can be more specific in intensity of speed, agility and aerobic endurance. From this the athletes can perform much better in games tactically and avoid potential burnout. They can also be less susceptible to injury. Creighton et al (2010) points out that GPS can be beneficial in a return to play capacity. A sports practitioner cant control the variables around a graded progressive approach to rehabilitation. The ability to complete specific drills, injury tests, sprint tests and tackling drills by using quantifiable data via GPS to identify the athletes current stage of rehabilitation mixed with a plan for the next stage shows a progression in the return to injury paradigm.

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Drawbacks of GPS

The use of GPS is most commonly used to measure distance covered at various speeds and the occurrence of high speed acceleration and decelerations. The validity of the results does however have to be questioned especially from a practical point of view. When there is a large number of players there generally wont be enough to go around so different players will end up using different units so variability in results has to be examined between the different units. Units used over a long period of time will be subject to software updates and effects on GPS measurements are unknown. Further to this, a study showed that there are large differences in measure variations between same brand and substantial differences with different versions. Therefore the use of GPS in team sports using different units has to come into question (Bucheit et al, 2014). There is also concern over the validity of of GPS systems during changes of direction. Moreira et al (2013) found from a study were athletes were monitored running in linear directions that the results showed very good accuracy between two different models of GPS but when the athletes went in non linear directions there was significant discrepancies between the known distance and the recorded distance travelled. Jennings et al (2010) continue to highlight limitations with GPS by highlighting that these devices are manufactured with different frequency levels of 5 and 10 Hz. The Hz is the number of times a signal is sent to the device per second meaning that a lower frequency of 5Hz is more likely to record inaccuracies in sprinting or changes of direction than that of its 10 Hz counterpart.

Here is a short video clip which demonstrates the beneficial uses of GPS within sport.

My view

My opinion of GPS is its a very useful tool in sport and has helped offer a new dimension of training athletes for competitiion. For me it certainly adds and contributes to the sports industry and will hopefully develop further in the future to eliminate some of the negatives that currently shroud its existance.

References
Aughey, R.J. (2011) ‘Applications of GPS Technologies to Field Sports’ International Journal of Sports Physiology & Performance. 6 (3) pp. 295-310.
Bucheit, M., Al Haddad, H., Simpson, B.M., Palazzi, D., Bourdon, P.C., Di Salvo, V. & Mendez-Villanueava, A. (2014) ‘Monitoring Accelerations With GPS in Football: Time to Slow Down?’ International Journal of Sports Physiology & Performance. 9 (3) pp. 442-445.
Creighton, D.W., Shrier, I., Schultz, R., Meuwisse, W.H. & Matheson, G. (2010). Return to play in sport: a decision based model. Clin J Sport Med. 20 (0), 379-385.
Cummins, C., Orr, R., O’Connor, H. & West, C. (2013) ‘Global positioning systems (GPS) and microtechnology sensors in team sports: A systematic review’ sports medicine. 43 (1) pp. 1025-1042.
Gabbett, T.J. (2010) ‘GPS Analysis of Elite Women’s Field Hockey Training and Competition’ Journal of Strength & Conditioning Research. 24 (5) pp. 1321-1324.
GoldCoastFC. (2012) ‘SUNS TV: Griffith Sports Science – GPS Tracking’ Online http://www.youtube.com/watch?v=s3dd2WAMXHo. [Last accessed 2nd may 2014].
Jennings, D, Cormack, S, Coutts, A.J., Boyd, L,J. & Aughey, R.J. (2010) ‘Variability of GPS units for measuring distance in team sports movements’ International journal of sports physiology and performance. 5 (1) pp. 565-569.
Kurzawa, D.A. (2008) ‘GPS in sport: Analysis and determination of fitness levels’ Final year thesis. University of South Wales. 1-62.
Moreira, A., Costa, E.C., Lodo, L., Freitas, C.G., Arruda, A.F.S. & Aoki, M.S. (2013) ‘Validity and reliability of GPS receivers in relation to the distance covered’ Revista Andaluza de Medicina del Deporte. 6 (4) pp. 146-150.
Reid, L.C., Cowman,J.R., Green, B.S & Coughlan, G.F. (2013) ‘Return to play in elite rugby union: Application of Global Positioning System technology in return-to-running programs’ Journal of sport rehabilitation. 22 (1) pp. 122-129.