Performance behaviour: Korfball Fitness

 

Preface

Previously in the article ‘Korfball Theory’ we discussed the characteristics of korfball actions.

At the level of the team, two functions are distinguished: ‘Attacking’ and ‘Defending’.                                                  

With the team function ‘Attacking’ there two team tasks: ‘Building up’ and ‘Scoring’.                   Building up starts in the defence zone after intercepting the ball, then the ball is transported to the attacking zone through teamwork (transition).  In the attacking zone the four attacking players cooperate in different roles to create scoring opportunities.                                                                                                         If it succeeds in creating a scoring chance, the team task of’ building up’ becomes the team task of ‘scoring’.                                                                                                                                                                         The purpose of the team task ‘scoring’ is by performing attacking korfball actions such as distance shot, running- in shot or V-shot. A goal is scored when the ball has, from above, completely passed through the korf.  

In korfball there is a special obstacle during the building up. After intercepting, the ball must be played to the attack zone. In the attack (or after the throw off) an attacker first receives the ball, then the shot clock starts counting down from 25 seconds. The 25 seconds is a time-limit. The attacking team exceeds the 25 seconds time-limit to attack by neither scoring a goal nor making the ball touch the korf from a shot by a player in the attacking zone. This time-limit is indicated by a shot clock. Exceeding the time-limit is indicated by the buzzer of the shot clock. After exceeding the time-limit, the referee stops the game and awards a restart to the defending team.

The team function ‘Defending’ also has two team tasks ‘Disturbing build up’ and ‘Preventing scoring chances. Players make use of defending korfball actions such as a ‘1 on 1 defence’, ‘cooperation in roles as front defence and back defence’.                                                                                                                The ultimate form of preventing scoring chances is winning the ball. Preventing goals in korfball is mostly done by defending tightly the attackers (lock down defence) and so neutralise the attackers. Attackers exceed the time-limit.

A special transition rule in korfball is: After very two goals, the divisions switch so attackers become defenders and vice versa. .

 

Team functions		Attacking		Defending
Team tasks	Building up, creating scoring chances	Scoring	Disturbing build up Winning the ball	Defending or hindering shooting Preventing scoring
Korfball actions	Passing; assisting; receiving; catching; rebounding. Creating free positions	Distance shot; Running-in shot. V-shot	Pressing the attacker; pressing the ball line. Not allowing free position	Interception passes. Blocking shots; winning the rebounds

 

 

Korfball fitness

In top-level korfball, in our case the Dutch korfball league, it is important for the players to deliver the ability for an optimal performance in one match and every week, a league long, (about 20 matches) time and time again. It is not only about quality but also quantity delivery of korfball actions. It is about sustaining korfball actions, better, longer, and more actions in the korfball context and recovering quickly after korfball actions. This ability is called korfball fitness.

This korfball fitness requires something other than a score from the Cooper test or from a shuttle-run test. Research in team sports has shown that a (korfball) specific training is effective. These findings have given rise to more intensive korfball training interventions to secure high stroke volumes, which, in turn, have proved positive in changing both maximal oxygen[1] consumption and korfball performance in terms of distance covered for position changes, contacts with the ball and number of accelerating and decelerating in a game (team tasks and associated korfball actions). 

Korfball-specific training is more effective in improving korfball fitness than any form of training. A korfball action consists of Communication (visual and auditory), Decision (cognitive), Execution of decision (motor). Korfball ability says something about the degree to which players can perform korfball actions. In korfball it is not about one action, but about different actions that you must perform more than once. Top korfball players can fulfil all roles in attack. (shooter, attacker, rebounder, and connector). Moreover, they can switch from one role to another at a high pace. This makes top korfball different from lower-level korfball. This switching of roles within the attack requires insight, cooperation, and coordination. Communication based on reading the teammates and reading the opponents requires continuous position changes and role changes in top korfball.                                                                                                                                                                          From the position of the defenders in korfball, there is also Communication, Decision making and Execution. Defending is usually a re-action to attack. When building up the attack, the initiative can also lie with the defence. The quality of front- defence and back- defence as team tasks is very dependent on the execution of agreements. Back – defence often forces a 2-2 attack pattern. The 1-on-1 duel is usually a re-action (a response) to what the attacker shows.  But it is also possible that the defender forces the attacker into positions whereby the initiative lies with the defender, e.g., pressing the ball lines, pressing running lines. Top korfball players must perform both team functions, attacking and defending, about 72 times during a match, about 24 minutes. Top players must maintain many action and good actions, at a high tempo and with precise timing.

That is why players need korfball fitness. Players try to achieve that during training.                           Korfball fitness is being able to sustain Communication – Decision making - Execution longer and being able to perform Communication – Decision making - Execution more often in a certain period of time.  This increase in ability is only possible if there is an overload in specific korfball training.  This means that the best players should always practice with the ‘best teammates’ and against the ‘best opponents'. Overload is acting better and longer and more often. So, an improvement in quality can develop (i.e., overload on Communication, Decision making and Execution[2]). Higher resistance = less time/space to act. But in korfball fitness, it is all about sustaining this longer than once: as many times as necessary in a match of 50 minutes of pure playing time.

Korfball fitness is a specific concept that defines the workload of a competition performance. The Korfball Fitness concept includes Communication, Decision Making, Execution Decisions, as much as possible to play at a higher tempo with a correspondingly precise timing and to keep this up for as long as possible, to maintain for 50 minutes, 25 minutes in attack and 25 minutes in defence.  

 Defining this workload of the Korfball League match is necessary to arrange training sessions in which korfball fitness (ability) is developed at the desired level. Unfortunately, defining the precise workload is not so easy. For this purpose, it is necessary to interpret the figures of Korfball League matches. The statistics of matches can help for that.

In a korfball match, there is always a moment of rest after the transition. When the ball is in attack, the defence has a rest and vice versa. We know by now how often (on average) a ball enters the attack and thus also how often the ball enters the defence. On average, there are 36 attacks and therefore 36 defences.

During the 36 attacks, through cooperation and communication, korfball actions must be taken to create a free chance to score or shoot and then rebound (keep ball possession) to start another series of attacking actions. The communication, decision making and execution of the decision, which are visible in free running, accelerating, and decelerating with changes of direction; passing and receiving the ball; shooting and rebounding, happens under pressure from the opponents who want to reduce the chances of success. To get a free position by the attackers, is done by accelerating and decelerating with changes of direction and the difference in tempo to surprise and to mislead the opponent.

The pure playing time of attacking is 25 minutes. The total time of attacking during a match for one zone is about 12 minutes. So, on average one attack lasts 20 seconds. So, after an attack, the defence of a team must defend for an average of 20 seconds. But here immediately comes a problem. The average figure of 20 seconds per attack is deceptive. The length of an attack can varies by many seconds.  The attacking rebound is an important factor.

The average score of a match in the Korfball League is 24 goals. A team that scores more than 24 goals is usually the winner. Scoring more than 24 goals per game is a proof of quality. A Korfbal league team needs 85 - 120 chances to do so.

Summary: A team's attack gets the ball 36 times on average. The 36 attacks must produce about 43 shot chances and 12 goals in 12 minutes to be able to speak of quality korfball fitness. The defence of a team must perform in a way that the number of attacks (36), the attack time (12 minutes), and the shot attempts (85 – 120) are reduced so that the opponent’s attack does not score 24 goals.

Training korfball fitness can be combined well with training the playing style. In fact: The playing style determines how you organize the korfball fitness training.

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[1] Korfball is a sport where the aerobe system functions as a basis, but where oxygen is mainly used to recover. For explosive action ('anaerobic', a 1v1) the phosphate system is used. After such an action, oxygen is used again to recover.

2 see: Korfball Coaching.