Category: Strength testing

New paper: Physical Predictors of Skeleton Performance

This week I had another paper published. This paper was part of the PhD studentship of Dr. Steffi Colyer in partnership with Bath University, GB Skeleton, UK Sport and my previous role at the BOA.

In this work we looked at the testing battery for strength and power assessment of bob skeleton athletes and identified predictors of skeleton performance. The analysis approach revealed that 3 tests scores can obtain a valid and stable prediction of bob skeleton start performance. More work from Dr Colyer’s excellent PhD will be published soon, so follow her work as I am sure more applied approaches in other sports will be followed in the next years. I enjoyed working with a great group of colleagues, athletes and coaches for this project and the publication reminded me of how fortunate I was in my time in the UK.

This project is a good example of how some applied sports science projects can advance understanding of specific performance issues as well as provide meaningful advice for the coaches and practitioners involved in this particular sport.
The abstracts is below:
Int J Sports Physiol Perform. 2016 May 1. [Epub ahead of print]

Physical Predictors of Elite Skeleton Start Performance.



An extensive battery of physical tests is typically employed to evaluate athletic status and/or development often resulting in a multitude of output variables. We aimed to identify independent physical predictors of elite skeleton start performance overcoming the general problem of practitioners employing multiple tests with little knowledge of their predictive utility.


Multiple two-day testing sessions were undertaken by 13 high-level skeleton athletes across a 24-week training season and consisted of flexibility, dry-land push-track, sprint, countermovement jump and leg press tests. To reduce the large number of output variables to independent factors, principal component analysis was conducted. The variable most strongly correlated to each component was entered into a stepwise multiple regression analysis and K-fold validation assessed model stability.


Principal component analysis revealed three components underlying the physical variables, which represented sprint ability, lower limb power and strength-power characteristics. Three variables, which represented these components (unresisted 15-m sprint time, 0-kg jump height and leg press force at peak power, respectively), significantly contributed (P < 0.01) to the prediction (R2 = 0.86, 1.52% standard error of estimate) of start performance (15-m sled velocity). Finally, the K-fold validation revealed the model to be stable (predicted vs. actual R2 = 0.77; 1.97% standard error of estimate).


Only three physical test scores were needed to obtain a valid and stable prediction of skeleton start ability. This method of isolating independent physical variables underlying performance could improve the validity and efficiency of athlete monitoring potentially benefitting sports scientists, coaches and athletes alike.
[PubMed – as supplied by publisher]

>Nintendo wii fit can be used as a force plate?


Apparently it is possible to use the Nintendo Wii Balance Board as a measurement device. In fact, the Nintendo wii balance board is a simple force platform capable to sampling data at 100Hz.


Balance Board Internals

The Wii Fit offers for a low cost price a simple platform with four measuring sensors and can be used with very little effort as a simple and inexpensive force plate, even without the corresponding game console. A German company has developed a software solution to measure some key parameters;

Clark et al. (2010) suggested that the Wii Fit balance board could represent a valid cheap solution to measure standing balance. Furthermore they have recently suggested the use of the infrared cameras in the hand controllers as a possible alternative to expensive timing light systems ( Recent work from Young et al. ( also suggests the possibility of using this technology for developing bespoke diagnostic or training programmes that exploit real-time visual feedback of current Centre of pressure position.

The Wii Balance Board is certified for 300 pounds (136 kg) in Japan and 330 pounds (150 kg) in the U.S. The Wii Balance Board has four sensors, so each sensor is certified for up to 136 kg / 4 = 34 kg per sensor in Japan or 150 kg / 4 = 37.5kg per sensor in the United States.The following Wii Balance Board calibration information from WiiBrew will make more sense.

If you are interested in Linux, you can see here how to extract the force data. I am sure this is not something useful to measure high performance athletes. However it could represent a fun and simple tool for diagnostic measurements in some populations.

If you have one and are able to use it for this purpose let me know!

Strength and Conditioning Book

They say better late than ever, in this case it took few years, but eventually the project is now completed and the book will be out on the 17th of December.
It all started with a chat at a conference few years ago with my colleagues and friends Rob Newton and Ken Nosaka discussing the need of a comprehensive textbook on strength and conditioning providing information on the biological bases as well as practical applications.
This book is finally a reality thanks to the help and support of many colleagues who agreed to contribute to this project providing excellent chapters and creating a unique resource which we hope will be well received by anyone interested in Strength and Conditioning.

This book provides the latest scientific and practical information in the field of strength and conditioning. The text is presented in four sections, the first of which covers the biological aspects of the subject, laying the foundation for a better understanding of the second on the biological responses to strength and conditioning programs. Section three deals with the most effective monitoring strategies for evaluating a training program and establishing guidelines for writing a successful strength and conditioning program. The final section examines the role of strength and conditioning as a rehabilitation tool and as applied to those with disabilities.
The book is already available on Amazon and other online booksellers in hardcover and paperback editions.
A big thanks to our production team at Wiley-Blackwell and all the colleagues contributing to the chapters.

Details of the chapters are available here:
Foreword (Sir Clive Woodward).
1.1 Skeletal Muscle Physiology (Valmor Tricoli).
1.2 Neuromuscular Physiology (Alberto Rainoldi and Marco Gazzoni).
1.3 Bone Physiology (Jörn Rittweger).
1.4 Tendon Physiology (Nicola Maffulli, Umile Giuseppe Longo, Filippo Spiezia and Vincenzo Denaro).
1.5 Bioenergetics of Exercise (R.J. Maughan).
1.6 Respiratory and Cardiovascular Physiology (Jeremiah J. Peiffer and Chris R. Abbiss).
1.7 Genetic and Signal Transduction Aspects of Strength Training (Henning Wackerhage, Arimantas Lionikas, Stuart Gray and Aivaras Ratkevicius).
1.8 Strength and Conditioning Biomechanics (Robert U. Newton).
2.1 Neural Adaptations to Resistance Exercise (Per Aagaard).
2.2 Structural and Molecular Adaptations to Training (Jesper L. Andersen).
2.3 Adaptive Processes in Human Bone and Tendon (Constantinos N. Maganaris, Jörn Rittweger and Marco V. Narici).
2.4 Biomechanical Markers and Resistance Training (Christian Cook and Blair Crewther).
2.5 Cardiovascular Adaptations to Strength and Conditioning (Andy Jones and Fred DiMenna).
2.6 Exercise-induced Muscle Damage and Delayed-onset Muscle Soreness (DOMS) (Kazunori Nosaka).
2.7 Alternative Modalities of Strength and Conditioning: Electrical Stimulation and Vibration (Nicola A. Maffiuletti and Marco Cardinale).
2.8 The Stretch–Shortening Cycle (SSC) (Anthony Blazevich).
2.9 Repeated-sprint Ability (RSA) (David Bishop and Olivier Girard).
2.10 The Overtraining Syndrome (OTS) (Romain Meeusen and Kevin De Pauw).
3.1 Principles of Athlete Testing (Robert U. Newton and Marco Cardinale).
3.2 Speed and Agility Assessment (Warren Young and Jeremy Sheppard).
3.3 Testing Anaerobic Capacity and Repeated-sprint Ability (David Bishop and Matt Spencer).
3.4 Cardiovascular Assessment and Aerobic Training Prescription (Andy Jones and Fred DiMenna).
3.5 Biochemical Monitoring in Strength and Conditioning (Michael R. McGuigan and Stuart J. Cormack).
3.6 Body Composition: Laboratory and Field Methods of Assessment (Arthur Stewart and Tim Ackland).
3.7 Total Athlete Management (TAM) and Performance Diagnosis (Robert U. Newton and Marco Cardinale).
4.1 Resistance Training Modes: A Practical Perspective (Michael H. Stone and Margaret E. Stone).
4.2 Training Agility and Change-of-direction Speed (CODS) (Jeremy Sheppard and Warren Young).
4.3 Nutrition for Strength Training (Christopher S. Shaw and Kevin D. Tipton).
4.4 Flexibility (William A. Sands).
4.5 Sensorimotor Training (Urs Granacher, Thomas Muehlbauer, Wolfgang Taube, Albert Gollhofer and Markus Gruber).
5.1 Strength and Conditioning as a Rehabilitation Tool (Andreas Schlumberger).
5.2 Strength Training for Children and Adolescents (Avery D. Faigenbaum).
5.3 Strength and Conditioning Considerations for the Paralympic Athlete (Mark Jarvis, Matthew Cook and Paul Davies).