By West Bromwich Albion FC, in collaboration with Liverpool John Moores University
JB Morin presented alongside Jonas Dodoo at the first of a two-part masterclass series entitled Speed Development for Team Sports. The event was organised and hosted by West Bromwich Albion FC of the English Premier League, in collaboration with Liverpool John Moores University. The aim of the two masterclasses was to provide attendees with high level speakers within speed development, from both a research and practical perspective. The second masterclass, taking place on November 30th, will see Dr. Paul Brice deliver on the biomechanics of sprinting and lessons learned from the Olympic track; and, Prof. David Bishop on repeated sprint ability.
JB (@) is currently Full Professor at the Faculty of Sport Sciences of the University Côte d’Azur (Nice, France). He is Head of Sports Performance Research at the Laboratory of Human Motor Function. He obtained a PhD in Human Locomotion and Performance at the University of Saint-Etienne in 2004. JB’s field of research is mainly human locomotion and performance with specific interest in running biomechanics and maximal power movements. He has published over 80 peer-review journal articles since 2004, a large number of which are open access through his Research Gate page:
Sprint Force – Velocity – Power Profiling: Field Methods, Performance, Injury Management
Fast and Slow Thinkers
JB began his presentation by discussing the relationships between practitioners and those working in research. A researcher’s role is to aid those in the field in selecting the right resource to achieve an outcome by providing suggestions to what may be useful and what may not.
He described researchers as slow thinkers who take their time and follow the scientific method to try to provide answers to questions arising in the field. Conversely practitioners are fast thinkers who create questions and need to work out answers more quickly. It is important that research and practice work together to better answer the questions and problems arising in the field.
You can read more on this topic in Professor Aaron Coutts’s IJSPP publication ‘Working Fast and Working Slow: The Benefits of Embedded Research in High-Performance Sport‘.
Sprint Acceleration: Force – Velocity – Power
A main focus of JB’s current research is into Force – Velocity – Power profiling. He notes that all team sport athletes require power and that sprinting (acceleration) and jumping are crucial to match outcomes. Power is a function of Force and Velocity, consequently it is important to work out which of these the athlete requires most and train it accordingly.
He claims physiology dictates that somebody cannot be a tractor and a Ferrari at the same time. Force production is highly Velocity specific and there is no supported link between being able to produce a lot of Force at a low Velocity and a lot of Force at higher Velocity. But, at different times during sprinting, both are needed. It is therefore crucial to understand how an individual produces power. The typical laboratory methods of assessing somebody’s F – V – P profile involve costly and impractical equipment such as an instrumented sprint treadmill or a track loaded with force plates. Both of these highly accurate and reproducible, however neither are particularly useful for practitioners in the field.
Mechanical Effectiveness of Force Application
Another key area of JB’s research is looking into force application and the concept of Ratio of Force. He is known for championing the importance of horizontal Force to acceleration, and claims that an athlete must look to produce a greater amount of total Force (generally gym based) but also improve the effectiveness that this is applied with (technical training). This is one of the reasons Christoph Lemaitre was able to run sub 10 seconds in the 100m without any previous strength training, because his effectiveness on the ground was very good.
It was interesting to hear that everybody will see a step after step decrease in their Ratio of Force, even Bolt! Elite sprinters are just able to reduce this linear decrease in effectiveness. JB has seen footballers generally lose around 8% in this ratio, whereas Christoph Lemaitre will only see a 4% decrease. Due to the importance of horizontal impulse to acceleration, reducing this decrease is crucial in improving performance.
Assessing F – V – P in the Field
Going back to JB’s original points on the researcher – practitioner relationship, how are these theories then applicable in the field? As part of his research group, JB has looked to validate more accessible methods of assessing an individual’s F – V – P profile. These are mainly from mathematical equations derived from Speed – Time curves during a maximal sprint. From this, individual F – V and P – V curves can be calculated. These methods are all validated and freely available through JB’s Research Gate page.
Even simpler than this method, JB aided in the development of the My Sprint app. F – V – P profiles are plotted automatically on the app by using a simple phone camera and some poles. The app is able to compute these from the user defined splits of the sprint.
As S&C coaches and Sport Scientists (fast thinkers!) we ultimately want to know what this means for our programming. JB tied together all of his research with a few practical examples. He gave an example of two Barcelona youth team players with similar 30m times. However, when profiled, they presented very differing ways of achieving this. Player 1 was significantly more Velocity proficient, whereas Player 2 was able to produce a lot more Force. To make these two players faster would require very different programs. The first player, being deficient in Force, would need to spend more time in the gym than player 2; maybe even being put at unnecessary risk by following a Velocity focused program.
JB has numerous good examples of how differing profiles can produce similar acceleration abilities. The next logical step is to look at the most efficient way to train for these individual profiles, to rectify deficiencies and improve performance. His group are due to be releasing a paper in the near future of one such example of this. They found that Very Heavy Sled Training (80% and above BM) was a very successful method in increasing somebody’s horizontal Force output. The training group saw improvements in Force, Power and Ratio of Force; and consequently faster 5 and 20m times.
To conclude his presentation, JB presented some research on how a F – V profile can be used with injury management in mind. A paper he was involved in showed that footballers returning to play following hamstring injury maintained pre injury Velocity ability, but had a reduction in Power and Force; these didn’t return to baseline for another two months. Therefore, it is questioned what functional data led to a return to play decision, and what potential risks may be present during these two months.
Following this study, the group observed F – V profiles of a whole squad longitudinally through a season. They observed that those injured during the period had either lower than the squad average Force capabilities or saw a major drop in these prior to the injury. It is hypothesised that monitoring F – V – P profiles could prove to be a viable method in a teams’ injury management strategy.
JB presented a fantastically well researched theory that S&C coaches and Sport Scientists could easily apply to their own practice. His presentation followed a clear path through his groups’ research, with practical examples throughout. I would highly recommend anybody that has the opportunity to go along to any of his seminars or workshops; reading journal articles and blogs only scratches the surface of JB’s theories, and nothing can beat discussing them with the man himself.
Look out for our future write ups from Jonas Dodoo’s presentation, as well as the second masterclass in this series by Dr Paul Brice and Professor David Bishop. To experience the second masterclass in person on November 30th visit: wbafcspeedmasterclass2.eventbrite.co.uk