The Line-Out

The lineout in rugby union is used as the method of restarting play after the ball has gone into touch. As many as all eight players of the pack line up in two parallel lines perpendicular to the sideline with a space of approximately 1m between them. The ball is thrown down the centre of this line by one member of the pack, usually, but not necessarily, the hooker.

Except in the case of a penalty kicked directly to touch, the team that did not put the ball out of play throws it into the lineout, where possession is contested by the two teams and it is retrieved from the air by a player, usually from the side throwing the ball in. Players will in almost every case jump to retrieve the ball and in the modern game of rugby the jumper is supported in his upward flight by supporting players, and held in place for a short period at the peak of flight. Rarely is the jump for the ball made without assistance.

The team throwing the ball into the lineout benefits from prior knowledge of the precise destination of the ball, but possession is very dependant upon a number of factors, including: timing of the throw and jump, accuracy of the throw, and elevation of the jumper. The factors influencing the accuracy of the throw have been discussed previously (An Analysis of Throwing Techniques in the Rugby Lineout) on this website, this paper discusses the factors influencing the lifting/elevation of the jumper and the catching of the ball while in the elevated position.

Part 1: Lineout Jumping

For full understanding of the mechanics of lifting the reader should first read the principles of Countermovement in Part 2: Background Information.

Elevation.

Advantage is gained if the jumper is in a position to catch the ball at a greater height than the opposition. To attain maximum elevation of the catching hands the jumper must be fully extended and held at arms length by the two players lifting. While there are variations of the lift in which the jumper is held at waist level the maximum height will be increased if the jumper is held below the buttocks, and this presentation describes that method. Lifting the player to this fully extended position requires a coordinated series of actions of both the jumper and the lifters and an understanding of lifting mechanics.

Initiation.

In all supported lifting the jumper begins the action with a countermovement, a step or drop followed by a full extension of all three joints in the leg. The mechanics of the countermovement are reasonably complex (see Counter Movement) but suffice to say that the effect of the applied force is increased significantly if the countermovement is well used. In addition the upward force must be applied through a full range of movement to increase the take-off velocity, and final height (see Concept 4). In all lineout jumping it is important that the jumper initiate the movement. Whether the optimum result is the height jumped or stability at peak flight, the reality of the game is that with all three athletes cooperating there is a conservation of energy by each player. The reality of rugby is that energy conserved in any individual skill, is energy still available as the game nears its conclusion. Lineout jumping should be regarded as a cooperative skill that is practised, and learned.

First lift.

The force required to assist a jumper is determined not so much by the mass of the jumper, but by the increase in vertical velocity required to reach the peak position. If the jumper is already moving upward then the lifter requires less effort, so the two actions must be coordinated. As the jumper makes the first upward movement the lifter begins to lift with arms. As a consequence simply of the mass of the lifted player the lifter's arm flexion is slowed considerably at take-off and the reaction to this is a slight dropping motion in the lifter's legs, just as in "cleaning" a bar. In effect this "loads" both the leg extensors and the arm flexors, providing the lifter with an increased level of force production. The lifting player should begin with bent legs and arms - knees at approximately mid range, elbows close to the body and at mid range - and as the jumper begins the take off action the lifting player first absorbs the force, then responds. With intelligent use of the principles of countermovement maximum elevation can be gained, with, importantly, minimal energy expenditure.

Second lift

While the front lifter serves a balance control function he/she also assists by maintaining the required upward motion and by adjusting the leg position of the jumper. This aids in keeping the jumper vertical during the lift. (Note that in the example (fig 2) the front lifter has arms bent and is balancing the jumper in the held position.)

Extension/Completion

The action of the lifter is a coordinated arm and leg movement. As the jumper nears peak height the lifter can assist full arm extension by bending the knees slightly as the arms straighten, then finish the movement with a final leg extension, (like a weightlifters clean.). In addition, the lifter should at this stage step forward into the required position to make a final balance adjustment.

Hold

While maximum force is best applied at an intermediate joint angle, the contrary turning moment - torque - is also greatest at that position. Consequently as the lift is completed the hands must be brought in close toward the line of the body to bring the centre of mass of the lifted player close to the base of the rear lifter. To facilitate this action the lifter should begin the lift standing close to the jumper, then as the jumper rises, step forward with one foot to adjust the final balance. With hands rotated inward the jumper has a stable "seat" from which to retrieve the ball, and this seat is further stabilised by the jumper leaning back slightly (this of course influenced by the opposition and the flight of the ball.). In maintaining this held position it is essential that not only is the lifter fully extended but the jumper must also make an effort to extend, to feel the tension in his body. This tension ensures that the lifted player may move to retrieve the ball while the two supporting players continue to provide support and balance of a stable body unit. The extension will ensure control right through the catching activity and will enhance not only the ability of the jumper to retrieve the ball, but also control of the descent to whatever ball delivery is selected.

Grip.

There are several variations available, two are described here. A grip at the bottom of the legs of the shorts, with hands at the back of the jumper's thighs as in the top view, works well and provides a good strong lifting position. However while successful during the lift it may result in some difficulty at the top when the stable held position is required. The lower picture shows the lifter holding the jumper's thighs with thumbs on the inside and below the buttocks and it can be seen that the lifter is in a slightly more crouched position. This grip places the lifter at a slight disadvantage compared to the shorts grip as it tends to force the elbows out to the side, changing the line of force application. This grip however does provide a much more efficient position at full extension. (In a gymnastic or dance situation the lifted athlete would be held at the side of the thighs only with hand pressure.) As the lift begins, hands are on the back and outside of the thighs with thumbs pointed toward the inside, or grasping the shorts, but as the peak of flight is reached the arms/hands rotate inward so that the held jumper is in effect "sitting" in the lifters hands, allowing the lifter to lock his elbows and hold the position. Control during lifting is enhanced if the lifter is able to grasp the shorts of the jumping player but coaches must identify which of the two is more successful for their players. With younger players in particular, ensure that shorts be of sturdy, non slippery material.

Stability.

While we are aware that a wider base improves stability, we must recognise that the front lifter plays a major role in adjusting the balance of the jumper. In that case the front lifter should not form part of the balance base, rather the rear lifter should stand almost directly beneath the jumper, with the front player providing the balance control in the held position. To facilitate this all three must be well versed in the principles of balance and rotation. The front support then, by grasping the jumpers legs at the appropriate height, rather than simply pushing, may control both left/right and front/rear rotation. As in all other techniques, practice is required and may be facilitated using physical guidance (see Guidance p15).

Ball Capture.

While being in position to capture the ball is of primary importance, the player must also be skilled at actually catching the ball. That of course is a basic rugby skill that will not be addressed here but catching the ball in the lineout whilst being held in the air is often more difficult with the problem stemming from the jumping action itself. Beginners or players with poor technique may prepare to catch with elbows to the side (fig 4), and then bring the hands together to make the catch. This makes clean catching more difficult as the timing may not be quite right and the ball will go between the hands. While the coach may simply instruct the jumper to jump with elbows at the side there are physical guidance activities that will ensure the correct action. (see Catching p11)

While the player jumps for the ball from a position on either side of the centre line, the ball, in theory, is in the middle, between the two lines of players. The jump then, in most cases, is toward the centre of the line (fig 5), leading often to instability, and in a worst case, overbalancing and falling. To counter that action we might make use of the principles of the conservation of angular momentum, as described in Newtons Leap below.

Newton's Leap.

From the angular analogue of Newtons 3rd Law. Coaches are welcome to call this what they will!

This proposal works very well mechanically but like all well learned activity must be practised and it is recommended that initial learning take place using physical guidance. As mentioned above, in a perfect situation the player and the ball are on slightly different lines and the jumper tends to leap into the middle of the line to retrieve the ball, often compromising balance. This proposal provides a method by which the jumper is lifted in the original line, but is able to retrieve the ball from the centre of the lineout. This of course provides an advantage as the jumper may be protected from the opposition not only during the jump, but also upon landing without the lifters having to move their feet and risk unbalancing the combination.

To complete this manoeuvre, the jumper leaps directly upward. At peak of flight he leans toward the centre of the line but bends at the waist with both his feet and his hands/head moving into the centre of the lineout. As he/she is supported by the major lifter at buttock level, below the centre of mass, the effect of this will be for the hips to move to the outside of the lifted line while the legs/arms move to the centre. This of course entails some lateral movement in opposite directions by both lifters, but with the line of the centre of mass between the two. The major support is now outside the line of centre of mass, so it is essential that the front support at this stage be equally beyond that line, on the inside of the line, and the lifters learn to shift their position as required. The forward lifter helps control this manoeuvre by assisting the movement of the jumper's legs toward the centre, while the rear lifter maintains the stable support. With practice, the three may soon develop an understanding that allows the front lifter to hold quite low on the jumper's legs and play a major controlling role in the movement. With ball in hand the reverse movement occurs, taking the captured ball away from the centre of the line.

The described action allows the jumper to reach over into, and even beyond, the centre of the lineout without compromising balance and risking the possible unbalanced landing. It is essential however that all must be aware of the lifting and balance mechanics of the movement, especially the need for the jumper to be in an extended position.

An extension of this action could well include turning and piking in the opposite direction after ball capture. This would have the effect of taking the ball from the centre of the line and delivering it to the receiver well beyond the line of the original lineout.

In the pictures above (fig), the ball is not high enough to allow the thrower to catch comfortably, and the front lifter is holding too high on the jumper's thighs.

However, it can be seen that the lifted player is on balance and is able to reach well into the centre of the lineout without compromising that balance. A player reaching into the lineout without the contrary action of the legs will tend to rotate in that direction leading to an uncontrolled descent and landing with, perhaps, loss of possession.

Teaching the Jumping Skills

Physical Guidance

The use of physical guidance techniques in the beginning stages of learning lineout jumping and lifting techniques is very beneficial. In keeping with the principles of skill learning a guidance system provides good positional feedback for both the jumper and the lifters, and as a bonus reduces the threat of injury from collapsed lifts (see A Physical Guidance System p15). From this very controlled situation accurate lifting positions and correct lifting and holding actions may be practiced in accordance with the principles of graduated feedback. The assistance gradually reduced as the techniques become learned.

In the absence of such a system, or once the basic skills have been learned, the lifted player may be lifted to grasp a high bar or rope allowing the coach to make adjustments to the position of the lifters.

There are three basic concepts for practice:

Counter Movement

All jumping and lifting must utilise the counter movement principle. Learning and practice should be in conjunction with coordination practice and involve the "loading" of the appropriate muscles immediately prior to a contraction. This is commonly achieved by stepping into a jump, or "taking the weight" in lifting. In throwing and passing the principle is demonstrated by use of the backswing.

Force Summation

Whether there be a guidance system or not, it is suggested that once the basics have been learned the coach and athletes develop a timed sequence of lifting actions so that players may develop an internal timing mechanism to support the coordinated action. The emphasis in this case should be in the initiation of the lift by the jumper, followed by the lift of the major lifter and the final extension utilising the balance activity of the front lifter. Throughout, the principles of counter movement and balance must be adhered to.

The combined effect of the jumper's initial leap, followed in order by the 1st and 2nd lifters will be to maintain - and even increase - the original take-off velocity, gaining maximum height. We might call this 1,2,3 or anything else that similarly indicates that several actions follow in sequence as described earlier. The essential practice is of a coordinated sequence with all three players knowing and understanding the principles.

Force summation is maximised when a throwing or jumping action is continued through a full range of motion. Whether the athlete jumps using a countermovement or from a static position, height is maximised when there is complete extension through a full range of motion of all of the joints involved in the action. Athletes who jump must learn to do this. While games like volleyball and basketball encourage athletes to develop a jumping ability, to apply force through the full range is a conscious act. Lineout jumpers can be taught to jump through the full range of motion using feedback from an observer who simply watches for the full extension of knees and ankles at take-off and encourages the jumper to complete the motion. Mechanical feedback systems like a jump and reach board, or a contact mat, provide immediate objective feedback to support the observations. It is recommended that all players learn to jump with full extension; the concept is applied in many activities in the game of rugby. .

Balance

To maintain a stable balance position with the jumper at full height, the centre of mass of the system - all three - must be within the confines of the base. In this case the base is formed by the four feet of the two lifters but in practice the centre of mass of the jumper should be very close to or even within the base of the rear lifter. This allows the front support to fill a balancing role. In this case it is essential that the rear lifter positions himself close to the jumper with hands close to his body as the lift is made.

While these principles may be learned and practised using the physical guidance system lineout players involved in both lifting and being lifted should be exposed to and practise acrobatic/circus type lifts and balances. This activity will develop kinaesthetic awareness and an understanding of the techniques required to improve lineout performance. The activity might also be presented as a team building activity and there are practitioners in every city who might well serve as a source of information and assistance in this specialist area.

Part 2: Background Information

Tension

The human body is made up of a number of segments, (bone connected to bone at joints), with muscle contraction providing the forces that generate motion at the joints. All human motion is generated in this manner and from the day a small child begins to move under it's own power, the jointed human system learns to use muscle tension across the joints to stabilise the body segments against the forces that tend to disrupt motion. The major disrupting force in the first instance is gravity and the child soon learns to maintain sufficient tension across the appropriate joints to walk and run efficiently. As more advanced locomotor skills are learned, the learner is exposed to the requirements of more complex motion and learns to use muscular tension across the joints to maintain integrity of the whole body unit in the particular advanced skills environment.

Young gymnasts learn that to maintain and control body position while performing basic balance activities, it is necessary to maintain tension across the joints. They learn that to perform handsprings and cartwheels and similar activity it is necessary to maintain full extension at the joints to enable the body to respond optimally to reaction forces at take-off and landing and maintain body position in the air during flight. Similarly skaters, dancers, divers, and trampolinists learn that to keep the joints extended at take-off and landings and to maintain tension during the movements between is the major component not only of form, but all movement control.

The thrower/jumper in track and field learns that the one essential feature of all of the events in the field is to maintain tension in the whole body while applying force to the projectile being launched, whether it be a discus, or the human body. Like the gymnast, the pole-vaulter learns to store energy in the apparatus by maintaining tension during the storage phase, then again in the rockback and flight phase to ensure the full return of the stored energy. If the body is allowed to behave as a series of floppy segments at any stage, the performance founders.

In effect, the athlete in every one of these activities learns that for the body to act as an efficient unit there must be stability and transfer of forces through the body utilising tension at the joints during the activity. The body must maintain its integrity as a single unit. Beginners and inefficient performers often have not learned this basic principle and allow the body to behave rather as a series of independent segments.

The same principles apply in rugby. When the player learns to tackle he learns to maximise the application of force to the opposition by maintaining tension in the body during the activity. During the scrum or ruck or maul the player learns to apply force to the opposition in the most efficient direction and through the most efficient joint angles, while using tension to maintain body shape and integrity during the process - "spine in line". Similarly the lineout jumper maintains his body position at peak flight, and his lifters their stability, by using tension across the joints to resist disruptive forces and maintain accuracy.

These examples may seem obvious, but in many team games the importance of body tension in other than a few specific activities has been ignored. The point should be made very clearly that whether the activity be whole body motion or a simple accuracy task, for optimum performance there is always the absolute need to maintain tension across all of the appropriate joints of the body.

Counter Movement

An important aspect of muscle mechanics relates to the speed with which the muscle shortens while active. We refer to the three general phases of muscle activity as:

Lets say a muscle can produce a certain amount of force in an isometric situation. If this muscle then acts concentrically - contracts - the maximum force it can produce depends on the speed at which it shortens. The muscle can produce less and less force the faster it is required to shorten. The opposite is true for eccentric muscle action. The faster a muscle is stretched while attempting to shorten, the larger the forces it can produce. This relationship is referred to as the force-velocity relationship of muscle and is shown in the figure alongside. In practice this means that we have trouble generating large forces when our muscles are shortening at high speeds. This suggests that if we could slow down the speed of muscle shortening we may be able to improve performance. This commonly happens during the force production phase in a standing vertical jump.

First of all, our two-joint muscles are active and they have a reduced speed of shortening because of their skeletal attachments. Second, we introduce an eccentric muscle activity phase by dropping prior to the upward motion. This movement forces the quadriceps to become active during the drop in order to stop the downward movement, which means the knee extensors are acting eccentrically and are thus able to produce larger forces than if they were acting concentrically or isometrically. Third, as we accelerate our arms upward in the second half of the phase we generate forces that act downward into the ground which not only loads a further eccentric force into the leg extensors, but increases the ground reaction force which drives us upwards.

Jumping in the lineout is a standing vertical jump, and all of the above factors are involved in increasing vertical jump height. The jumper will as a matter of course tend to use the countermovement by either dropping slightly prior to the jump or stepping into the take-off. More importantly though the same force-velocity relationship can be utilised by the lifter to aid force production in that action also.

As the jumper begins to rise from the ground the rear lifter begins to apply an upward force through both the arms and legs to assist that motion. The mass of the jumper however is greater than arms alone can lift, and the immediate response to the lifting action is to slow the concentric muscle action in the elbow flexors. This increases force production at that site and also causes the leg muscles to resist the contrary downward force. Contraction of the leg muscles to stop that downward reaction is an eccentric action that immediately becomes isometric, providing increased force production. Again, it is essential that a coordinated series of actions is used to get the best response.

Movements utilising the countermovement concept may be referred to as "loading," which refers to the isometric contraction of the muscles concerned. It is not only used by sprinters in the blocks as they push the heel back in the "set" position and by throwers in the windup preceding a throw, but also by all vertical jumpers in every sport.

Practice Theory

While practice theory can be quite complex and theoretical, there are some basic principles that should be adhered to in teaching lineout skills:

Massed Practice

This type of practice is proven to be beneficial for the learning of discrete, closed skills. When the movement must be grooved, the player should, as the name indicates, repeat the skill over and over again. This must be supervised by a coach to ensure that it is the correct skill that is being practised. Care must be taken too that the number of throws or lifts in any one session is not so great that the skill level becomes degraded. Note that it is not only fatigue that may influence the quality of this practise, but often the novice player just loses concentration. If the performance does fall off it is good practice to leave the skill and return after having a rest or doing something else similar (see Distributed Practice below).

Later in the development of the player, the autonomous stage, massed practice is also beneficial. Just as the best golfers in the world may drive a hundred balls on the driving range, then so may the lineout participants practise a large number of throws with the same trajectory, or a large number of supported lifts, and take responsibility themselves for the correctness of the practice.

Variable Practice

Once all types of throws and lifts have been learned and practised the coach should introduce a regime where the particular throw and lift required is decided prior to the activity, as in the game situation. Research indicates that this type of practice is particularly effective but only if each variation of the skill is well grooved.

Distributed Practice

This refers to the placing of the particular skill within the total practice time. In this case, the lineout throw may be inserted in the total practice session at different times, so that the player has lineout throwing practice interrupted by some other unrelated specific practice like scrummaging or sprints or a tactics discussion. During those other activities there is an awareness that the lineout practice will be repeated later in the total practice time and as a consequence there is an element of memory processing and mental preparation.

Mental Practice

Research confirms that mental practice, in association with physical practice, is superior to just physical practice. The implication for coaches is that in the learning of skills and drills and the practice of existing motor patterns, the athlete should be encouraged to:

• prepare to practise by watching others and visualising themselves in that situation
• discuss performance with the coach and mentally rehearse suggested changes
• "run" the expected movement just prior to performance
• develop a habit of "thinking about" their specialist roles often
• imagine novel situations and their solution, the "what if?"
• set performance goals for practice

A Physical Guidance System

Lifting and Support

Physical guidance is commonly used to teach beginners new skills and techniques when there is a possibility of injury or damage to the athlete, or the environment. We use a simulator to teach our pilots before trusting them with an aeroplane and dry land drills before allowing beginning divers to enter the water with scuba apparatus. In activities in which gravity plays a significant role, such as trampoline and springboard diving, we use belt and pulley systems to provide the athlete with time to learn new moves in the air. Acrobats and dancers learning even simple balancing activities begin with the confidence builder of physical support while in the air.

In learning lineout jumping and lifting skills there is a period of time in which coordination between individuals is developed and the most efficient and accurate positions of all three are confirmed in both the lifting and holding actions. Using traditional methods, the rear lifter often stands too far away from the jumper and even amongst competent athletes there are many crashes. The use of a physical guidance system not only removes these crashes completely from the learning situation, but also provides the coach with a method whereby each member of the threesome can experiment with different techniques, and adjust their position without fear of collapse and consequent injury.

The obvious system to implement this learning assistance is the rope and pulley. In this case a short bar - or two rings - at the end of the rope for the jumper to hold onto both during the lift and while at the top. The rope is fed through a pulley above the learning area - the roof or a specially constructed frame - and as the jumper rises into the air the coach or an assistant takes in the slack and using a cleat or similar, holds the jumper at peak height. With this support the coach is able to provide instruction and physically move players into a correct stance during the lift and at full extension. Very quickly both lifters learn the most efficient lifting action and the best position for stable support. (Note that it is essential that in operating any guidance system such as this that gloves be worn by the operator.)

As learning occurs and the lift becomes more efficient the bar may be positioned at peak height allowing the lift to be "natural" but providing support at the peak. Using this variation the coach may introduce new and more difficult skills such as Newton's Leap performed at the peak.

The benefits of physical guidance are many and well documented. (Schmidt and Wrisberg 2001) Specific to the lineout they are:

• The coach is provided with the time to move players into correct position during the lift and at peak height.
• Players learn to recognise the correct lifting action and the most stable balance position without fear of accident.
• Assistance may be reduced as the appropriate rate learning takes place.
• There is no chance of accident in the initial learning phase.
• Learning is faster!

Catching

The Perfect Catch trainer is a commercially available physical guidance system that is designed to enhance catching in the lineout. It is simply a padded strap that restricts the path of the hands of the jumper and has proven to be useful in modifying catching behaviour of lineout jumpers. Detailed information on the product and suggestions for learning techniques may be obtained at www.speedpowerstability.com.

Biomechanical Principles

(Adapted from Sanders & Wilson 1991)

These Biomechanical Principles can be applied in every facet of the rugby game. All are presented but those pertinent to this presentation are referred to within the document and discussed appropriately below:

1. Apply forces in the direction in which you want the object to travel.
   Jump/Lift - by standing close to the jumper the primary lifter is better able to apply the lifting force straight up.
2. Position the body to effectively produce ground reaction forces.
   Jump/Lift - the lifters are better able to apply optimal forces from a position close to the jumper
3. Generate the necessary ground reaction forces by utilising the large muscles of the body.
   Jump - the jumper begins the jumping action by raising the arms and dropping slightly before using the major muscles of the legs.
   Lift - the lifter begins with the arms then as movement begins drops slightly to complete the movement with the large muscles of the body.
4. Choose an appropriate combination of force and time to produce the desired change in motion. (Impulse)
   Jump - The jumper ensures that the force is applied through the full range of all three joints, hip, knee and ankle.
   Lift - The lifter ensures that the combination of arm and leg lift is one continuous motion through the full range of the movement.
5. Reduce impact forces by changing the motion over a long period of time.
6. To produce a large velocity of release use a large number of joints in a sequence from large (mass) to small.
7. Select an appropriate velocity of release, angle of release, and height of release to produce the desired result.
8. In activities in which the human body is projected, performance may be enhanced by redistributing the body mass about the centre of gravity.
   This is perfectly demonstrated in the discussion on Newton's Leap.
9. Stability is increased by increasing the area of the base of support, moving the centre of gravity towards an expected perturbing force, and lowering the centre of gravity.
   While the base of support may be widened to provide increased stability by the two lifters standing further apart, or each standing with legs spread, the constraints of the real lineout situation in which the supporting players may be required to move, and the principles of supported balance, make this concept not completely applicable in this situation.
10. To produce rotation, apply the force away from the axis of rotation.
    If there is an eccentric (off centre) force applied during the lift there will be unwanted rotation. The force must be applied through the centre of mass of the jumper.
11. Increase rate of rotation by redistributing the mass close to the axis. Decrease the rate of rotation by redistributing the mass away from the axis.
12. Optimise release velocity of an object by a suitable combination of rate of rotation and distance of an object from the axis.