HumanBrakingPerformance

Author: Dr Damian Harper (Founder of Human Braking Performance) The ability to rapidly decelerate horizontal momentum is a critical locomotor skill required for athletes competing in multi-directional sports. In previous blogs I have highlighted the unique force demands associated with intense braking when decelerating rapidly and the implications this can have for performance enhancement, neuromuscular fatigue and injury-risk. One notable unique demand associated with deceleration and braking is the necessity to skilfully generate and attenuate forces throughout the lower limbs (see video 1). This can place substantial force demands on muscles and connective tissues to generate the high internal joint extensor moments required to control joint flexion and to mechanically buffer and absorb energy with minimal damage, which could be caused through fast eccentric muscle action (i.e., active muscle fibre fascicle lengthening/strain). As illustration, when required to decelerate horizontal momentum rapidly, ankle and knee joint flexion velocities can be around 380 and 470 degrees per second, respectively (1).  https://humanbrakingperformance.com/wp-content/uploads/2025/02/Basketball-brake.mov Video 1. Basketball player braking to perform a rapid horizontal deceleration. Necessitates ability to skilfully generate and attenuate forces throughout the lower limbs!    Given the significance of horizontal deceleration to athletes competing in multi-directional sports, there should be special interest devoted by sports science and medicine practitioners on how to optimally enhance their athlete’s horizontal deceleration ability (i.e., we want to improve our athlete’s ability to perform and be resilient to one of the most mechanically demanding tasks they will be exposed to during competition – deceleration). We have previously highlighted that this could be done by enhancing two key modifiable factors: 1) horizontal deceleration skill and 2) horizontal deceleration specific strength qualities – both of which interact to enhance horizontal deceleration ability (2). One notable strength quality that is critical for horizontal deceleration is eccentric strength (3). This is primarily due to eccentric strength being associated with the generation and control of joint motions when braking centre of mass momentum (i.e., velocity x mass) in any movement plane, and secondly, due to eccentric muscle actions being capable of generating much higher forces than those observed when performing concentric muscle actions (see Figure 1A). This may explain why athletes are able to generate greater rate of change in velocity when performing horizontal decelerations compared to horizontal accelerations during competitive match play (4), thus enabling them to rapidly reduce their momentum in very short distances and times.  The Role of Flywheel Eccentric Strength Training? Whilst there are many training modalities and techniques to enhance eccentric strength (Figure 1B), the use of flywheel training devices could be particularly beneficial for enhancing horizontal deceleration and braking capabilities. I first purchased an Exxcentric flywheel training device back in 2016, realising at first hand the unique stimulus that this training modality could provide for enhancing deceleration and braking performance capabilities. An example of this, was the potential to use a flywheel exercise within a warm-up to achieve superior horizontal deceleration performance compared to a warm-up without inclusion of a flywheel exercise (5).   Figure 1. Eccentric strength training for enhanced horizontal deceleration. (A) Force-velocity curve for dynamic eccentric and concentric muscle actions. Intense horizontal decelerations demand high eccentric strength capabilities across a range of eccentric velocities. Red arrows indicate need to increase eccentric force across a range of eccentric velocities to enhance horizontal deceleration ability. (B) Eccentric strength training modalities that can be used to enhance horizontal deceleration with equipment options and training methods. Adapted from Franchi & Maffiuletti (6).   Specifically, when using a flywheel training device, inertia generated in the concentric propulsive phase of the movement must be subsequently decelerated with a high braking action during the eccentric phase on every repetition of the set (7). This is not possible with traditional (isoweight) resistance training, where muscle activation is submaximal throughout the entire eccentric phase of a set, and up to the “sticking-point” during the concentric phase of a set (8). Therefore, traditional resistance training can be prone to ‘underloading’ the eccentric braking phase (9), which is not favourable for developing the braking and eccentric strength qualities required to rapidly decelerate horizontal momentum, such as when ‘pressing’ and changing direction repeatedly in multi-directional sports!  Traditional resistance training can be prone to ‘underloading’ the eccentric braking phase, which is not favourable for developing the braking and eccentric strength qualities required to rapidly decelerate horizontal momentum, such as when ‘pressing’ and changing direction repeatedly in multi-directional sports! Damian Harper This is in agreement with professional soccer practitioners, where there is a high consensus that when flywheel training is implemented regularly into soccer training regimes it can have a profound effect on enhancing a player’s change of direction (COD) performance capabilities (10). These perceptions are also evident in experimental data, where just one session per week of flywheel parallel squats (inertia: 0.11 kg.ms-2) performed over a 10-week period elicited significantly greater increases (effect size = moderate-to-large) in COD speed performance in comparison to a group who performed the same exercise with a traditional loading approach (i.e., 80% 1-RM) alongside routine soccer specific training (11). Interestingly, the flywheel training group had greater increases in eccentric quadriceps peak torque, whereas the traditional group had greater increases in concentric quadriceps peak torque, demonstrating adaptations specific to the training stimulus. Therefore, the authors concluded that training with flywheel squats likely led to greater braking abilities which transferred to enhanced deceleration and COD speed performance (see Videos 2-4).  Indeed, systematic reviews examining the use of flywheel training all highlight beneficial responses of flywheel training on COD performance for athletes competing in multi-directional sports, with these findings further summarised in an umbrella review on the topic (12). Therefore, flywheel training seems a particularly effective training modality for facilitating enhanced eccentric braking capabilities that transfer to enhanced horizontal deceleration and COD performance.  https://humanbrakingperformance.com/wp-content/uploads/2025/02/SDC-1.mov-Flywheel-incline-squat.movhttps://humanbrakingperformance.com/wp-content/uploads/2025/02/SDC-2.mov-Flywheel-incline-split-squat.movhttps://humanbrakingperformance.com/wp-content/uploads/2025/02/SDC-3.mov-Flywheel-Incline-SL-squat.mov Videos 2-4. Hand supported squat variations (parallel, split, and rear foot elevated) performed on the kBox Pro by Exxentric demonstrated by Chris Cervantes, Assistant Strength and Conditioning Coach of the Houston Texans American football team. Hand supported squat variations provide greater stability, but also allow

Author: Dr Damian Harper (Founder of Human Braking Performance) Given the significance of horizontal deceleration to athletes competing in multi-directional sports, there should be special interest devoted by sports science and medicine practitioners on how to optimally enhance their athlete’s horizontal deceleration ability. In other words, we want to improve our athlete’s ability to perform and be resilient to one of the most mechanically demanding tasks they will be exposed to during competitive match play! The Braking Performance Framework was published in September 2024 in the International Journal of Strength and Conditioning, with the aim of providing practitioners with practical recommendations and guidelines on how to enhance horizontal deceleration (Harper et al., 2024). Within this blog I wanted to provide a short overview of the framework and the training solutions that can be used to optimise preparation of your athlete’s horizontal deceleration and braking capabilities.   The Braking Performance Framework is illustrated below:  The key goals of the Braking Performance Framework are to: 1. Increase Braking Force Control 2. Increase Braking Force Attenuation I have discussed the importance of these two goals in a previous blog where I define what horizontal deceleration ability is and the importance of this skill for sports performance and injury-risk reduction. It is also important to highlight that a key aim of the training solutions and targeted adaptations is to help protect the health of the athlete from the very high forces encountered when decelerating (i.e., help build damage resilience). This is why we have previously described deceleration as a ‘critical mediator’ that can moderate the athlete’s external movement behaviour and ability to perform other high-intensity actions such as sprinting, changing direction and jumping (Harper & Kiely, 2018). This aligns to the phrase “you will not speed up what you can’t slow down” and further highlights the importance of increasing your athlete’s horizontal deceleration ability for both performance and injury-risk reduction purposes. Another important aspect of the Braking Performance Framework is the use and illustration of a ‘mixed method’ training approach that integrates exercise categories and training solutions targeting both local (i.e., general structure and function) and global (i.e., braking co-ordination/skill) specificity. Therefore, the different exercise categories and training solutions should be used interconnectedly to best promote transfer to enhancement of horizontal deceleration ability.  Horizontal Deceleration Ability“A players ability to proficiently reduce whole body momentum, within the constraints, and in accordance with the specific objectives of the task (braking force control), whilst skilfully attenuating and distributing the forces associated with braking (braking force attenuation)“Harper et al. (2022) The Braking Performance Framework contains 3 main exercise categories, each comprising key goals (Table 1).  Table 1. Exercise categories within the Braking Performance Framework and key goals. Exercise Category Training Solutions Key Goals Braking Elementary Exercises (BEE) ·       High eccentric loading ·       Eccentric Yielding-Isometrics/Holding Isometric Muscle Actions (HIMA). ·       Pre-planned horizontal decelerations (no COD). ·       Assisted horizontal braking steps. ·       Eccentric landing control ·       Target specific adaptations to muscle-tendon neuromechanical structural properties to enable players to produce and tolerate higher horizontal braking forces. ·       Increase ability to attenuate shock through lower limbs. ·       Enhance limb and trunk sensorimotor control (i.e., dynamic stabilisation). Braking Developmental Exercises (BDE) ·       Fast eccentric loading ·       Fast concentric loading ·       Overcoming isometrics/Pushing-pulling isometric muscle actions (PIMA) ·       Oscillatory isometrics ·       Pre-planned horizontal decelerations with COD ·       Assisted horizontal decelerations ·       Increase ability to produce high net braking forces in less time (i.e., braking impulse/braking rate of force development). Braking Performance Exercises (BPE) ·       Unanticipated horizontal decelerations ·       Contextual horizontal decelerations ·       Game-specific horizontal decelerations (i.e., small-medium-large-sided games). ·       Enhance braking skills under constraints specific to the competitive environment (i.e., game-representative braking). Within each exercise category practitioners can choose a range of training solutions to target the required adaptations underpinning enhanced horizontal deceleration ability. For more detailed coverage of these training solutions and programming considerations readers should consult the full Braking Performance Framework article that can be accessed here. Also, in future blogs (keep tuned) I am going to focus in on some of these specific training solutions and how they help to enhance your athlete’s horizontal deceleration and braking capabilities. However, for now here is an example of a couple of exercises demonstrated by Chris Cervantes (Assistant S&C Coach, Houston Texans NFL) that are included in the Braking Performance Framework article. Here you can see assisted braking steps from the Braking Elementary exercise category (Video 1) and fast eccentric loading from the Braking Developmental exercise category (Video 2).    Video 1: Assisted 2-step braking sequence with use of 1080 Sprint. Video 2: Fast eccentric hand supported rear foot elevated split squat with band assistance https://www.youtube.com/watch?v=W4my_r_nzOo In conclusion, unlike horizontal acceleration and maximum sprinting speed capabilities little attention has been directed towards training strategies aimed at improving an athlete’s horizontal deceleration and braking performance capabilities. The Braking Performance Framework provides practitioners with a selection of evidence-informed training methods to optimize the preparation of an athlete’s ability to perform and tolerate repeated horizontal decelerations during match play. Dr Damian Harper is the founder of Human Braking Performance. He has consulted with many high-performance organisations and technology companies around the assessment and training of horizontal deceleration and braking performance. For enquires around consultancy, speaking or individual and group staff CPD please enquire through the Human Braking Performance website here. References Harper, D. J., Cervantes, C., Van Dyke, M., Evans, M., McBurnie, A., Dos’ Santos, T., Eriksrud, O., Cohen, D., Rhodes, D., Carling, C., & Kiely, J. (2024). The Braking Performance Framework: Practical recommendations and guidelines to enhance horizontal deceleration ability in multi-directional sports. International Journal of Strength and Conditioning, 4(1), 1–31. https://doi.org/10.47206/ijsc.v4i1.351 Harper, D. J., & Kiely, J. (2018). Damaging nature of decelerations: Do we adequately prepare players? BMJ Open Sport & Exercise Medicine, 4, e000379. https://doi.org/10.1136/bmjsem-2018-000379 Harper, D. J., McBurnie, A. J., Santos, T. D., Eriksrud, O., Evans, M., Cohen, D. D., Rhodes, D., Carling, C., & Kiely, J. (2022). Biomechanical and neuromuscular performance requirements of horizontal deceleration: A review with implications for random intermittent multi-directional sports. Sports Medicine, 52(10), 2321–2354. https://doi.org/10.1007/s40279-022-01693-0

Author: Dr Damian Harper (Founder of Human Braking Performance). In this short blog, I wanted to provide a quick overview of the chapter I wrote titled ‘Deceleration in Sport: Incidence, Demands and Implications for Training?’ which features in the book edited by Paul Jones and Tom Dos Santos titled ‘Multi-Directional Speed in Sport: Research to Application’. In this chapter and this blog ‘deceleration’ is referring to whole body horizontal deceleration that occurs prior to the many changes of direction that players perform in multi-directional sports. As I highlight in the opening paragraph of the chapter, deceleration has been largely overlooked in comparison to acceleration and maximum velocity sprint running capabilities, and this was the first chapter in the myriad of sports performance books purely devoted to deceleration! Deceleration is a highly complex movement skill requiring athletes to generate and tolerate high impact braking forces. The chapter commences by highlighting a definition of deceleration ability, which is a “players ability to proficiently reduce whole body momentum, within the constraints, and in accordance with the specific objectives of the task (i.e., braking force control), whilst skilfully attenuating and distributing the forces associated with braking (i.e., braking force attenuation)” (Harper et al., 2022). In my previous blog I go into more detail of the two key components of horizontal deceleration ability highlighted in this definition, including: 1) Braking Force Control 2) Braking Force Attenuation  The chapter then covers the incidence of decelerations in some of the most popular multi-directional sports, providing an overview of the frequency of high-intensity decelerations compared to accelerations. Interestingly, this latest data (mainly from GPS devices) continues to show greater frequency of high-intensity decelerations compared to accelerations in most multi-directional sports, which was a trend first reported in a review paper published by myself, Chris Carling and John Kiely back in 2019 (Harper et al., 2019). Understanding the demands of deceleration in competitive matches is a very important area of future work. There is a need to better understanding the context to why high-intensity decelerations are occurring, and opportunity for advancements in technology to provide more in-depth insights into the unique biomechanical and physiological demands of deceleration and braking. Insights into the biomechanical and physiological demands of deceleration are discussed, with the performance and injury-risk reduction implications summarised from our publication titled ‘deceleration training in team sports: another potential ‘vaccine’ for sports-related injury?’ (McBurnie et al., 2022). Figure 1 illustrates the potential performance and injury-risk reduction implications of deceleration training, highlighting why deceleration is so important for players involved in multi-directional sports. Figure 1. Potential performance and injury-risk reduction (‘vaccine’) implications fromdeceleration training in multi-directional sports.   To ensure players are prepared for these demands the chapter concludes by highlighting the physical and technical determinants of deceleration and the training solutions that could be implemented to target improvements in an athlete’s horizontal deceleration ability. The chapter proposes the use of a braking performance framework (BPF) that could be used by practitioners to help guide selection of training methods and exercises to enhance an athlete’s horizontal deceleration ability (more on this in future blogs). Finally, the chapter encourages future research into the effectiveness of training interventions that can be used to enhance player deceleration ability and reduce susceptibility to injury and fatigue that can be caused from deceleration activities.  The book ‘Multidirectional Speed in Sport: Research to Application’ can be purchased here.  Hope you enjoy the read!  References Harper, D.J. (2023). Chapter 5: Deceleration in sport: Incidence, demands and implications for training? In: Jones, P.A. & Dos’Santos, T. Multi-Directional Speed in Sport: Research to Application. (pp74-103). Routledge. Harper, D. J., Carling, C., & Kiely, J. (2019). High-intensity acceleration and deceleration demands in elite team sports competitive match play: A systematic review and meta-analysis of observational studies. Sports Medicine, 49(12), 1923–1947. Harper, D. J., McBurnie, A. J., Santos, T. D., Eriksrud, O., Evans, M., Cohen, D. D., Rhodes, D., Carling, C., & Kiely, J. (2022). Biomechanical and neuromuscular performance requirements of horizontal deceleration: A review with implications for random intermittent multi-directional sports. Sports Medicine, 52(10), 2321–2354. McBurnie, A. J., Harper, D. J., Jones, P. A., & Dos’Santos, T. (2022). Deceleration Training in Team Sports: Another Potential “Vaccine” for Sports-Related Injury? Sports Medicine (Auckland, N.Z.), 52(1), 1–12.