Contents of Blog Posts

1. Introduction
2. Needs Analysis
3. Reverse Engineering
4. Understanding Field Skills
5. Deceleration
6. Agility & Pre-planned Change of Direction Speed
7. Acceleration & Speed
8. Coaching
9. Conclusion
10. About the Author
11. References
12. Comments

Introduction

Improving the competitive performance of athletes in field-based invasion sports such as soccer calls for consideration of the technical/tactical (Turner & Stewart, 2014), physiological (Stolen et al., 2005) and biomechanical (Reilly et al., 2000) requirements of the sport. Although soccer is an intermittent sport that uses both the anaerobic and aerobic energy systems (Bangsbo, 1994), this Blog Post will focus on the biomechanical and perceptual aspects of field skills in soccer. By field skill, we refer to athletic skills such as deceleration, agility and speed.

Therefore, the aims of this Blog Post are threefold 1) discuss how we can identify and program field skills 2) clearly identify and understand the field skills and 3) describe what they look like in soccer in addition to as a general technical model.

Needs Analysis

To understand what field skills occur in soccer and how these occur, we as coaches need to develop a needs analysis which is specific to the sport (e.g. soccer) and the particular playing positions on the field (e.g. midfielder or winger).

To do this, of course we can draw on peer-reviewed literature to provide us with evidence-based information which can help form a needs analysis. However, to provide more context, notational analysis of a game or video clips of gameplay on YouTube can support this evidence-based analysis. It can provide more context into exactly how athletic tasks are executed and in what context they are carried out, such as the stimulus that causes these tasks to be carried out (Jefferys, 2008).

Reverse Engineering

Once this information is collected and at our disposal, we must begin with the end in mind. S&C coaches, I included, have all been guilty of losing sight of the end outcome during the decision-making processes of programming.

So, although we should start with the end in mind, we must also keep it in mind when selecting exercises, planning sessions and organising training phases to complete the process of reverse-engineering. Each session and its contents must support the improvement of a field skill. This is not to say general physical preparation shouldn’t be carried out, or general speed mechanics shouldn’t be taught, but that context must be applied eventually in aims of achieving true transfer.

This way, we can ensure that our programming process is context-driven so that we can maximise transfer to on-field performance and ensure that the drills we prescribe are integrated by athletes in sports-specific scenarios (Jefferys, 2008) and that the gym-based exercises we prescribe support the development of these field skills. It’s also important to note that the quality and context of coaching must align with these concepts too (Jefferys, 2008) and that sessions aims are made clear to athletes to ensure this process does not fall at the last hurdle.

Understanding Field Skills

Field skills in soccer can be categorised into three main groups:

1. Deceleration
2. Agility & pre-planned change of direction
3. Acceleration & speed

It’s important to note that despite being grouped, agility & pre-planned change of direction are completely independent skills (Young et al., 2015). as are acceleration & speed (Turner & Stewart, 2014).

As proposed by Jefferys (2006; 2006b), skills can be broken down into:

1. Initiation movements – Used to start movement or change motion (e.g. Side-step motion to move laterally whilst watching play).
2. Transition movements – Used to set-up a position where subsequent movement can be efficiently executed (e.g. crossover step to assume a position facing forwards).
3. Actualization movements – The final movement that determines success in an athletic task (e.g. following a transition with a sprint to beat an opponent).

Deceleration

Deceleration is defined as a rapid stop or decrease in the body’s velocity, followed by re-acceleration in a different direction (Hewit et al., 2011). This presents deceleration as a transition movement (Jefferys, 2008). Kinematically it can be described by a centre of mass (CoM) posterior to the feet with a full foot heel strike, small steps and a wide base with knee flexion. Kinetically it can be described by high braking forces, long ground contact times, high step frequencies and eccentric muscle actions of the quadriceps and gastrocnemius (Dintiman & Ward, 2003; Andrews et al., 1997).

Deceleration can initially and generally be trained as a closed skill over short distances (~5m) with a wide, set stance. From here, it can be progressed to a split stance before being progressed over longer distances (~10m) to stop at higher velocities and with higher forces being tolerated through the front leg. Gradual progression in deceleration is key as decelerations high a load that is 37% higher than accelerations per square metre (Harper & Kiely, 2018).

In soccer, decelerations alone could occur in circumstances such as; set decelerations are used as a transition from the initiation movement of acceleration to meet an attacker face on. A split deceleration could transition from the initiation movement of walking to a defensive backpedal with a change in the direction of play. These context-specific, isolated deceleration scenarios can be progressed from closed drills to games that have a visual stimulus to react to, which starts with initiation movements such as those mentioned above and finishes with a deceleration transition in a particular deceleration position.

Being a transition movement which precedes change of direction (CoD) and having a higher occurrence in small-sided games (SSG) (Turner & Stewart, 2014), sessions entirely dedicated to deceleration are likely unwarranted after initial phases of training have progressed through closed decelerations progressions and games as a foundation of competency with this skill is developed.

From here, sessions aimed at improving CoD, agility and SGG’s will likely provide a sufficient, context-specific deceleration stimulus as a transition movement, which also allows for time to be better spent developing these qualities too. Decelerations occur 2.9x more frequently than accelerations (Harper & Kiely, 2018).

Plyometrics that can support the development of deceleration include Hop & Land variations in multiple directions (e.g. forwards, lateral and backwards). Strength exercises that can support the development of deceleration include exercises such as Stationary Lunges where the front leg absorbs force in knee flexion.

Example deceleration session:

1. Skill rehearsal – 5m Set Decelerations
2. Direct field skill development – Walk to Backpedal Deceleration Chase
3. Supporting plyometric/ballistic/jump – Forward Soft Hops
4. Supporting specific strength exercise – Forward Lunge Push (video example shown below)
5. Supporting general strength exercise – Goblet Split Squat

Agility & Pre-planned Change of Direction Speed

Sprints that include a CoD precede 6% of all goal-scoring situations in soccer (Faude et al., 2012). Even though this may appear low, players cover an average of 217 + 165m through multidirectional sprints (Castagna et al., 2003), accounting for 3.5% of their total distance. From a time-motion perspective, players change direction every 3.8 – 4.5 seconds (Bangsbo, 1994).

However, true Change of Direction Speed (CoDS) in invasion sports is rare (Jefferys, 2011), defined as a pre-planned task where “change of direction” occurs (Sheppard & Young, 2006). Albeit, closed CoDS drills can be used be as general tissue preparation to develop eccentric strength, dynamic balance and concentric rate of force development as a physical foundation to agility without a cognitive component. Constraint-based drills using something such as a cone drop can encourage athletes to lower their CoM, assume a sharp shin angle and push off the inside edge of their outside foot to promote good CoD mechanics.

Drills can be supported by ballistic exercises such as a Skater Hop & Land or Reactive Skater Hop & Land. These can be progressed to true Lateral Hop variations, where the direction travelled is entirely lateral and rebound components can be introduced. Strength exercises as Lateral Lunge Falls, Lateral Lunges & Cossack Squats can support the development of strength and dynamic balance through shorter or larger ranges of motion and faster or slower velocities, respectively.

On the other hand, agility is defined as a “rapid whole-body movement with a change of velocity or direction in response to a stimulus”. With a change of velocity being agility, deceleration alone could be performed as an offensive agility transition (Young et al., 2015). For example, an attacker could decelerate in a split position as quickly as possible to lose a defender and receive or pass the ball.

Also, offensive soccer players often perform rapid whole-body movements which are ‘tight’ and deceptive, such as slow jogging initiation movements with possession of the ball, before drop stepping laterally in a particular direction as a transition, before finishing with a sprint in the opposite direction as an actualisation movement to break away from defenders. Oppositely, a defender may have been jockeying as an initiation movement to stay with the attacker, followed by a side-step transition to follow the attackers drop step. With the attackers drop step being a fake move, the defender may be required to perform two transitions by then planting and crossover stepping the opposite side of their body to try and catching the attacker by finishing with an acceleration sprint and/or tackle.

After extensive closed CoDS drills have been executed, extensive and intensive open agility drills can be performed to mimic these game-specific movements, such as ‘Sharks in the Tank’ or a Double Circle Agility chase as shown below. Ultimately, these drills can be progressed to SSG’s (Turner & Stewart, 2014), where the most game-specific agility actions can be executed.

Example Change of Direction session:

1. Skill rehearsal – Change of Direction Mechanics
2. Direct field skill development – 180° Cone Drop Shuttle Race
3. Supporting plyometric/ballistic/jump – Soft Skater Hop & Land
4. Supporting specific strength exercise – Lateral Shoulder Box Battles
5. Supporting general strength exercise – Goblet Cossack Squat

Example Agility session:

1. Skill rehearsal – Side-step.
2. Direct field skill development – Double Circle Chase (video example shown below)
3. Supporting plyometric/ballistic/jump – Unpredictable Multidirectional Hops
4. Supporting specific strength exercise – Lateral Partner Lunge Push
5. Supporting general strength exercise – Lateral Lunge

Acceleration & Speed

Linear acceleration and maximum velocity sprinting are soccer-specific actions which can impact the outcome of games (Little & Williams, 2005). Elite soccer players average 17m per sprint, with ~50% being shorter than 10m (Stolen et al., 2005) and only 4% reaching 30m (Bangsbo, 1994b). 45% of goal scoring scenarios are preceded by a linear sprint (Faude et al., 2012). Although forwards, wingers and full-backs perform more sprints compared to centre-backs and central midfielders, there doesn’t appear to be differences in sprint distances (Fitzpatrick et al., 2019). Forwards show superior sprint speed to other positions, with defenders and midfielders showing similar sprint capabilities, followed by goalkeepers (Haugen et al., 2020).

Sprinting bouts are often preceded by players already being in motion, therefore maximal velocity is not just achieved, but achieved at reduced distances (Little & Williams, 2005) whereas successful acceleration in team sports has been characterised by faster ground contact times and increased stride frequency (Murphy et al., 2003).  Acceleration in soccer can start as an initiation movement in a variety of ways such as standing, two-point start, facing side on, facing backwards, laterally moving side on, moving backwards or jogging forwards. This warrants acceleration training that is performed from a variety of static starting positions with a forward lean that is higher than the typical angle of 45°. This can also include stimuli such as a ball, where two players race for possession and are more likely to accelerate in an upright position as a transition and finish with an actualisation movement that results in possession of the ball.

Although the characteristics of soccer gameplay highlighted above show a difference in how sprinting in soccer occurs differently to track sprinting, it’s still important to teach efficient acceleration and speed mechanics through the appropriate drills, especially in youth athletes who are going through maturation. This can support the general development of efficient acceleration and speed which can underpin the success of these movements in context specific ways as athletes develop into senior players. As shown in the session examples below, generic technical work can be completed prior to context specific work in micro-dosed approach or depending on the athlete (e.g. youth or senior) favour technical or context specific work.

Longer distances races of up 30m can be utilised where athletes are already in motion, to enable them to reach maximum linear velocity. However, soccer players have also been reported to perform curved sprints (Fitzpatrick et al., 2019). It’s suggested that full-backs perform sharper, shorter curved sprints likely to chase down attackers, who perform larger angled sprints, likely to run around and behind defenders between 10-15° and higher, with the average being around 5°.

Curved sprinting can be kinematically described by an inwards lean and kinetically and higher mediolateral forces. This should be accounted for with curved sprinting chases that permit particular angles for attackers and defenders, with an attacker’s initiation movement of a linear jog or curved acceleration being an external stimulus for defenders to react to.

In youth athletes, backpedal sprinting has been shown to be a beneficial addition to forwards sprinting for the development of early acceleration (10m) (Uthoff et al., 2018) likely due to the altered short step mechanics (Wild et al., 2011). This is a common game-specific action that defenders perform to stay behind attackers that are moving towards them whilst continuing to watch play.

In the video below, defenders begin in initiation movement of walking, before performing a forward plant transition to finish with an actualisation movement of trying to beat/catch defender, with this drill being set-up as a chase due to space constraints. On the other hand, the defender is walking as an initiation movement in reaction to the attacker, before performing a 180° turn and accelerating forwards.

Example Acceleration session:

1. Skill rehearsal – Wall Hinge to Knee Drive
2. Direct field skill development – Walk to 180° Turn Chase (video example shown below)
3. Supporting plyometric/ballistic/jump – Broad Jump
4. Supporting specific strength exercise – Heavy Resistance Band March
5. Supporting general strength exercise – Goblet Squat

Example Speed session:

1. Skill rehearsal – 10m A Skip to 20m Wicket Tempo
2. Direct field skill development – 10m Jog to 30m Linear Race
3. Supporting plyometric/ballistic/jump – Stationary Metronome Pogo’s
4. Supporting specific strength exercise – Prone Hamstring Tantrums
5. Supporting general strength exercise – Single-leg Romanian Deadlift

Coaching

Stating clear aims for sessions (i.e. development of particular field skill) should be made clear to athletes to ensure they understand the why behind what it is they’re doing. Also, having clear consistent names for movements and exercises in addition to coaching cues is essential for athletes to understand what they are doing with minimal confusion.

To continue, infrequent and precise verbal and visual feedback should be provided to help athletes develop not with reliance but rather by conscious self-exploration with appropriate guidance where required (Jefferys, 2008). Finally, athletes must be asked to answer questions regarding not just the benefits of what they are doing to understand they know the what and the why, but in what game-specific context they will execute the drills they are performing, to bridge final piece of context-driven S&C, to ensure we as S&C coaches are truly improving on-field performance.

Conclusion

The main aims of this Blog Post were threefold 1) discuss how we can identify and program field skills 2) clearly identify and understand the field skills and 3) describe what they look like in soccer, rather than as a general technical model.

To conclude, S&C coaches should ensure they truly understand not only the demands of sports such as soccer and the individual positions, but how movements occur. S&C coaches must reverse engineer their programming process and work backwards from the end outcome to ensure their programming and coaching are context-driven to improve field skills and drive high on-field performance.

About the Author

References

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