AUSTRALIA PATENTS ACT 1990 INNOVATION PATENT Name and Address of Applicant: Suzanne Louise Fischer 3/72-74 Ourimbah Rd Mosman NSW 2088 Actual Inventor[s]: Suzanne Louise Fischer Address for Service: 1 PLACE PATENT ATTORNEYS+ SOLICITORS Suite 404 / 107 Walker St NORTH SYDNEY NSW 2060 FOR THE INVENTION ENTITLED: A strength, stability and motor control training system, method and apparatus The following statement is a full description of this invention, including the best method of performing it known to me/us: 5 INTRODUCTION The present invention relates to physical exercise, fitness and rehabilitation, and in particular a strength, stability and motor control training system, method and apparatus. 10 The invention has been developed primarily for use as a means for strength, stability and motor control training of the stabilising muscles of the body. However, it will be appreciated that the invention is not restricted this particular field of use. 15 COPYRIGHT NOTICE This document is subject to copyright. The reproduction, communication and 20 distribution of this document is not permitted without prior consent from the copyright owner, other than as permitted under section 226 of the Patents Act 1990. 25 PROBLEMS OF THE PRIOR ART It is known in activities of sport and daily living the body does not operate in isolated segments but works as an integrated and dynamic unit. Functional movements occurring in daily living or sport rely on the combination 30 and interrelation of the muscular, neural and skeletal system - this is known as the kinetic chain link model. According to the kinetic chain theory a biomechanical deficit in one region of the body can be responsible for symptoms in a distant body part. A biomechanical 35 system operates optimally when all parts of the chain link are able to generate and absorb forces appropriately. 2C 5 To train or re-train performance of a specific movement, a muscle or muscle group often has resistance applied to it in a very specific manner. This trained control of movement is accomplished by an intricate interplay of the muscular, skeletal and neural system with a complex three-dimensional geometry. Muscle units are 10 recruited as determined by the mechanical requirements to produce force, reduce force or stabilise the kinetic chain during functional activities. For example, a muscle group is trained to lift an object. This training takes the form of the muscle group lifting an object via the use of secondary or tertiary levers (the 15 skeleton being the primary lever). The addition of levers with attached weights changes: (1) the direction of an applied force on the muscle and/or surrounding muscles, and (2) the distance, speed and range of movement produced. 20 The concept of core/trunk stability aims to address the issue of motor control for the trunk. Trunk stability has been defined as the body's ability to maintain a neutral/stable spine following perturbation. 25 The role of the stabilising muscles of the trunk is to control direction-specific stress and strain. Stability of the trunk is dependent on neuromuscular feedback control in response to forces both internal and external. Known devices for muscle training do not address the issue of motor control. 30 Fixed-weight devices Strength training using various fixed-weight devices has been practised for decades. Machine weights, free weights, exercise resistance tubing, pulleys, medicine balls and kettle bells are all examples of known devices used for strength training. These known weight-lifting devices use a fixed weight (analogous to a 35 "dead" or constant load) to provide resistance. Training involves lifting (or pulling) against resistance provided by such fixed-weight devices. These devices do not 3C 5 sufficiently afford multi-planar movements, which are required to train the stabilising muscles of the body. A further disadvantage of these known devices is that the load is stable and that using such devices for training does not rely on proprioception and involves 10 predominantly an isolated single muscle. Therefore, with the use of free weights, it remains a challenge to teach a user to trigger the proprioceptive feedback required to activate a particular muscle or muscle group. Instead the movement of stable loads tends to favour the isolation of specific muscles. 15 An additional disadvantage of these devices is that their weight is fixed at the time of manufacture (either as a single weight or involving a means to add weights in fixed intervals). Additionally, the transportation and portability of such devices is therefore relatively limited and the costs of distribution on a commercial scale can be significant. 20 Variable strength training devices Variable strength training devices are available to consumers but do not have a means of altering the stability of the load or utilizing a "live" (e.g. moving) load. Examples of variable strength training devices include interchangeable dumbbells 25 and barbells where weight is added to or removed from a fixed bar. These variable strength training devices do not allow for a continuous addition of load in either a static or dynamic environment. Consequently, there is only ever an approximation of the suitability of the load carried to the user's requirements. 30 Proprioception deficiencies Proprioceptive deficiencies can be improved through training in stability and balance exercises. Loss of proprioception in major joints through the kinetic chain can produces unstable joints in other parts of the body. Examples of joints that 35 have a tendency to become unstable and which have a greater potential for injury 4C 5 include the shoulder, spine and knee. Impaired proprioception will increase the risk of injury to the joint as well as other joints throughout the kinetic chain. The shoulder joint is the body's most mobile yet most unstable joint. Being inherently unstable makes the shoulder joint prone to injury. If the forces travelling 10 through the shoulder joint, produced while performing everyday or athletic tasks (such as picking up an infant or throwing a javelin), are not controlled by the stabilising muscles the risk of injury to the shoulder joint and other joints of the kinetic chain greatly increases. 15 A weak stabiliser muscle in joints such as the shoulder inhibits the recruitment capacity of the prime movers. The more effective the stabilisers of the shoulder the more effective will be the power output of the prime movers, which aids a user in being able to throw the javelin more suitably (and possibly further), or being able to pick up an infant, without the risk of injury. 20 Known stability training devices Gymballs, wobble boards, Bodyblades T M and foam rollers have been used by physical trainers and therapists to train the stabilising muscles of the body and to enhance proprioception. The inventor is not aware of any known single device that 25 can be used for providing proprioceptive and resistance training of the stabilising muscles through the entire kinetic chain system. These known devices are used primarily to train the trunk stabilisers with the stabilisers of the upper or lower extremities. 30 Gymballs, wobble boards and foam rollers are used for stability training of the lower body stabilisers. They require the user to sit, stand or lie on the device, so cannot be readily used for training the upper body stabilisers. The Bodyblade T M is used for training the upper body stabilisers. It must be held in one or two hands, so is not useful in training the lower body stabilisers. It has the additional 35 disadvantage that it requires a minimum level of physical strength in the upper body to move or shake the device to set up oscillations in the blade. 5C 5 OBJECT OF THE INVENTION It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. 10 According to one aspect of the invention there is provided an exercise device for strength, stability and motor control training, comprising: (a) an elongate flexible member having a proximal and a distal portion, said proximal portion including a Handle, wherein said Handle and said flexible 15 member are configured to preclude a relative wrapping relation between them such that the length of said flexible member remains unaltered during any rotation of said Handle; (b) a Weighted Object comprising a weight-bearing object of a specified unit weight or a multiple thereof, said Weighted Object being attached to said 20 distal portion such that i. said Weighted Object is configured to act as a pendulum suspended from said flexible member and said Weighted Object tends to an oscillating state upon lifting said device by said Handle; and ii. said Weighted Object is able to be maintained substantially in an 25 equilibrium (non-oscillating) position by applying a restoring force to the Handle while lifting said device. According to another aspect of the invention there is provided an exercise device 30 for strength, stability and motor control training, comprising: (a) an elongate flexible member having a proximal and a distal portion, said proximal portion including a Handle, wherein said Handle and said flexible member are configured to preclude a relative wrapping relation between them such that the length of said flexible member remains unaltered during 35 any rotation of said Handle; 6C 5 (b) a closeable bag secured to said distal portion able to accommodate a Weighted Object such that one or more said Weighted Objects can be exchanged so as to comprise a weight-bearing object of a specified unit weight or a multiple thereof, said bag being attached to said distal portion such that: 10 i. said Weighted Object within said bag is configured to act as a pendulum suspended from said flexible member and wherein said Weighted Object tends to an oscillating state upon lifting said device by said Handle, and ii. said Weighted Object is able to be maintained substantially in an 15 equilibrium position by applying a restoring force to the Handle while lifting said device. Preferably, there is provided an exercise method for strength, stability and motor 20 control training, including the step of using an exercise device as hereinbefore described by lifting said device while simultaneously applying a restoring force to the Handle of said device, such that said Weighted Object is substantially maintained in an equilibrium (non-oscillating) position during lifting of said device. 25 BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention will now be described, by way of 30 example only, with reference to the accompanying drawings in which: FIGURE 1 is a front view of one embodiment (the Distributed Load Embodiment) of a device for strength, stability and motor control training according to the invention. 35 7C 5 FIGURE 2 is another embodiment of a device for strength, stability and motor control training according to the invention (the Central Fulcrum Embodiment). FIGURE 3 is another arrangement of the Central Fulcrum embodiment of a device for strength, stabilityand motor control training according to the invention. 10 FIGURES 4A and 4B show yet another embodiment of a device for strength, stability and motor control training according to the invention. This embodiment includes a Strap secured directly to a Weighted Object without the need for a bag (the Strap Embodiment). 15 FIGURES 5A and 5B show the Strap Embodiment of Figure 4 attached to a Weighted Object comprised of an everyday household item (in this example, a PET bottle). 20 FIGURES 6A to 6F contain exemplary bag shapes suitable for use in the embodiments shown in Figures 1 to 3. FIGURES 7A to 7E contain perspective views of exemplary arrangements of loops on the bag in the embodiment shown in Figure 2. The loops serve as means for 25 attaching a hook, whether directly or indirectly via string or strings fed through the loops. FIGURES 8A and 8B show the embodiment in Figure 2 in use. Figure 8A shows the embodiment in Figure 2 being used to perform a lateral raise exercise. Figure 8B 30 shows the device being used to perform a front raise exercise. FIGURES 9A and 9B show use of the embodiment shown in Figure 2 to perform a leg squat exercise. 35 8C 5 DETAILED DESCRIPTION A preferred embodiment of the present invention will now be described by reference to the drawings. The following detailed description in conjunction with the figures provides the skilled addressee with an understanding of the invention. 10 It will be appreciated, however, that the invention is not limited to the applications described below. Dictionary of defined terms 15 Table 1 is a dictionary of terms defined according to the invention. Terms defined in Table 1 are denoted with the use of capitalisation throughout the document. If a term is not capitalised then its plain meaning is to be construed, unless otherwise specified. 20 Table 1: Dictionary of defined terms Term Description Handle The part of the flexible member, or Strap, where force is applied to lift and move the load during training. The Handle and Strap are configured to preclude a relative wrapping relation between them. This may be further facilitated if the Handle is covered with a foam cover or a tube through which the Strap can be passed, for comfort and to facilitate relative pivotal movement between the Handle and the Weighted Object and to prevent the winding and unwinding of the Strap around the Handle. The Handle can be grasped by the hand to apply force or hooked over an upper or lower limb (e.g. hand, wrist, foot, ankle, knee) as the means for applying force. Strap An elongate flexible member, or Strap, of any suitable material, such as string, rope, cord or webbing attached to a Weighted Object to convert the Object in use to an unstable or "live" load. 9C In the preferred embodiment, the Strap is capable of carrying a variable load (a Weighted Object or Objects). Rubber cord (also described as exercise tubing, bungee cord or theraband) is also suitable and adds additional instability to the load compared with materials with less elasticity. Weighted Any suitable object that provides resistance (i.e. a weight-bearing Object(s) object of a specified unit weight or a multiple thereof) when using the present invention for strength, stability and/or motor control training. Examples include: a container (e.g. a P.E.T. bottle or plastic bag) filled with sand, water, rice, seed; a dumbbell; any object that can act as the desired load (e.g. a filled container of milk or juice, a bag of rice and so on to a desired or specified unit weight or multiple thereof); or a combination of such objects. In a preferred embodiment, the Weighted Object(s) is (are) placed in a bag that is secured to the Strap. This enables the Weighted Object or combination of Weighted Objects to be easily changed and so vary the load by desired unit amounts. In an alternative embodiment, a Weighted Object is attached directly to a flexible Strap. 5 The elements of the invention are now described under the following headings: Preferred embodiments Referring to the drawings, the present invention provides a system, method and 10 device for strength, stability and motor control exercise training, including for rehabilitation. The device in all of its embodiments enables the use of an unstable or "live" load in strength and stability training. The term "live" load is derived from structural 15 engineering and refers to a temporary or moving load. In this document, the term 10C 5 "unstable" load is also used in this way. The exercise device includes an elongate flexible member, or Strap, attached to a Weighted Object, so that the Weighted Object is suspended from the end of the Strap when the device is in use. The Strap causes the Weighted Object to oscillate about an equilibrium position when the device is lifted by the Handle. In the equilibrium position, the Weighted Object is 10 static and the restoring force applied by the user is equal to the applied force causing the Weighted Object to oscillate. The Handle and the Strap or flexible member are configured so that a relative wrapping relation between them is precluded when the Handle is rotated, so that 15 the length of the Strap remains unaltered during rotation. The Handle may be covered (e.g. with a tube), which facilitates rotation of the Strap within the handand further precludes winding or unwinding of the Strap around the Handle. Lifting an unstable load engages the local stabilising muscles of the trunk. This 20 invention aims to retrain and recruit the local and global stabilising muscles that hold the body's joints in position while performing everyday tasks. The invention provides a means to recruit the local and global stabilisers (by providing a means to train for fitness, conditioning or rehabilitation purposes using an unstable load). Movements using this invention are performed slowly with low, unstable loads. 25 Unstable, slow, low-load exercises train motor control. Known devices do not address the issue of motor control. Distributed Load Embodiment Referring to Figure 1, a preferred embodiment 10 includes: 30 1. an adjustable elongate flexible member, or Strap, 30 incorporating a Handle (with or without a cover 40); and 2. a bag 20 attached to the Strap, for accommodating a Weighted Object (not shown). One or more Weighted Objects is placed in the bag 20 to provide a load when the 35 device is being lifted. The bag 20 is capable of holding a variable load (the Weighted Object(s) can be varied) and is collapsible for transportation. For 11C 5 convenience, this embodiment will be referred to as the Distributed Load Embodiment because the Strap 30 is secured in such a way that the load is distributed rather than being concentrated at a single point on a single Strap (e.g. one end). In the preferred embodiment, there is a single Strap 30 and the load is distributed across the opposing ends of the Strap. This is in contrast with the 10 alternative embodiments described later in this document. One or more Weighted Objects (not seen) are placed into the bag 20 prior to use. The Distributed Load Embodiment in one arrangement includes a closing means 50 for closing the bag to prevent accidental spillage of the Weighted Object(s) from 15 the bag 20 during use. In one arrangement, the closing means 50 comprises buckle straps or similar, as illustrated in Figure 1. In another arrangement, the closing means 50 is a drawstring or similar covering over the opening of the bag, as shown in Figure 3 and described in further detail in relation to Figure 3. 20 In yet another arrangement (not illustrated) of the Distributed Load Embodiment, the invention includes more than one Strap (e.g. two Straps) so that the load provided by the Weighted Object is distributed across a plurality of Straps. This enables the invention to be used in training exercises that involve more than one limb or more than one person. 25 Central Fulcrum Embodiment Figures 2 and 3 show different arrangements of another embodiment 60 of a device for strength and stability training. For reasons described below, this 30 embodiment is referred to as the Central Fulcrum Embodiment. The elongate flexible member, or Strap, 30 and a Weighted Object (whether or not housed within a bag 20) are configured so that the load is concentrated at one point on the Strap 30 (in the examples illustrated, this is at one end of the Strap 30) and the Strap 30 acts as central fulcrum for the Weighted Object(s). 35 The arrangement in Figure 2 includes: 12C 5 1. an adjustable Strap 30 incorporating a Handle (with or without a cover 40); and 2. a bag 20 for housing one or more Weighted Object(s). The bag 20 has loops 90 around its perimeter, which can be secured internally or 10 externally to the bag. The loops 90 are illustrated in Figure 2 as side-seam loops. In Figure 3, the loops 90 are D-rings secured to the bag by a length of material or other means (e.g. sewn to the bag, not illustrated). String(s) 80 are fed through the loops 90. 15 The Strap 30 can attach directly to the bag 20 by any suitable means (e.g. tie, clip, buckle, eye/loop arrangement, knot) or via a hook 70 (e.g. a swivel-eye hook locking device or similar). The hook 70 can hook: 1. directly onto the loops 90 (not shown) of the bag 20; 2. onto one or more strings 80, which are fed through the loops 90 (see 20 Figure 2), to facilitate gathering of the loops 90 and/or to increase the length of the lever (see the section "A flexible Strap" for description of levers); or 3. onto one or more centrally positioned D-rings 100 through which the strings 90 are fed. 25 In either arrangement of the Central Fulcrum Embodiment 60, the configuration of strings 80, loops 90 and hook 70 serves the following functions: 1. it closes the opening of the bag 20 sufficiently to prevent accidental spillage of contents during use; and 30 2. it causes the Strap 30 to act as a central fulcrum, which further enhances the resistance perturbations (oscillations) during use; 3. the strings 80 enable gathering of the loops 90 toward the central fulcrum and may further increase the length of the lever. In the arrangement illustrated in Figure 3, the double strings 80 are easily adjusted in length, in 35 addition to the Strap 30. 13C 5 The string(s) 80 may be made of any suitable material, including string, webbing, cord, nylon rope, exercise tubing or the like. The string(s) 80 may be made of the same material as the Strap 30. Further exemplary arrangements of loops and strings are shown in Figure 7 10 namely: A. side seam loops with single string (compare with Figure 7F); B. cross corner loops; C. side seam loops; D. single Strap (no string); 15 E. double Strap (no string); F. side seam loops with double strings. Each of arrangements 7A, 7B, 7C and 7F can be used with single or double strings. Arrangements 7D and 7E represent single and double Strap configurations. Loops 20 and strings are not required for these arrangements, but can be used if desired. All of these arrangements are suitable for the Central Fulcrum Embodiment, including arrangements 7D and 7E which can also be used without a central fulcrum. Strap Embodiment 25 Figures 4 and 5 show a further embodiment of an exercise device for strength, stability and motor control training. This embodiment includes an elongate flexible member, or Strap, 30 secured directly to a Weighted Object. The Weighted Object can be any item with the desired weight, such as a dumbbell or a PET bottle filled with fluid, water, sand, etc. This enables the Strap 30 to be used with readily 30 available items in the home, outdoors or any fitness/gym setting. As with the other embodiments, the Strap 30 incorporates a Handle (being the part of the Strap 30 where force is applied), which may or may not include a cover or tube. 35 14C 5 In the Strap Embodiment, the Strap 30 may act as central fulcrum for the Weighted Object - as illustrated in Figures 4 and 5. In an alternative arrangement (not illustrated), the Strap 30 may be configured so that it attaches to the Weighted Object at more than one point. In this arrangement, the load is distributed along more than one point on the Strap 30. 10 As with the other embodiments, the Strap functions to destabilise the load by causing the load to oscillate and act as a pendulum suspended from the Strap when the device is in use. The Strap can be adjusted (not shown in Figures 4 or 5) to vary the load by varying the length of the Strap. The load can also be adjusted 15 by adding, removing or substituting a Weighted Object. The Strap Embodiment also includes an arrangement involving more than one Strap, so that the load is distributed across a plurality of Straps. This enables this embodiment to be used for training excercises that involve more than one limb 20 and/or more than one person. Uses of the present invention The present invention in all of its embodiments provides a single device for proprioceptive and resistance training of the stabilising muscles through the entire 25 kinetic chain system, including the local and global stabilisers. Apart from application as a strength, stability and motor control training device in general physical fitness and conditioning, the inventive device has a number of more specific applications, examples of which are described below. 30 Co-contraction and proprioception The key to the present invention involves the introduction of resistance perturbations resulting from lifting an unstable load. A perturbation is an applied force that causes destabilisation. One example of a perturbation is lifting or moving an unstable (or "live") load. The instability of the load (which tends to 35 oscillate about an equilibrium position when the device is in use) challenges the neuromuscular system and causes co-contraction of the stabilising muscles to 15C 5 overcome the instability. For example, when lifting an unstable load, research has found that there is a significantly higher degree of co-contraction of the abdominal muscles than when lifting a stable load. The mechanism for increased muscle co-contraction involves sensory feedback, in 10 the form of visual and proprioception feedback. This feedback during the perturbation encourages engagement or recruitment of the stabilising muscles to stabilise the load. Proprioceptive deficits throughout the kinetic chain can lead to an unstable joint 15 and increase of mechanical stress on contractile and non-contractile tissue. Such stresses can lead to repetitive micro-trauma, abnormal biomechanics and injury. For example, proprioceptive deficits have been demonstrated in recurrent ankle sprains and research suggests that patients with lower back pain have impaired proprioceptors in facet joints of the spine. Proprioception is a key component of 20 dynamic joint stability - the ability to appropriately activate muscles to stabilise a joint. Proprioception can be improved through training and such training can play an important role in injury prevention. This is because by improving proprioception, 25 improvements can in turn be made in engaging the stabilising muscles. This leads to greater joint control and reduces the likelihood of joint injury throughout the kinetic chain. Research has shown that co-contraction of the stabilising muscles (e.g. the 30 abdominal muscles) is significantly higher when lifting an unstable load. Lifting of stable loads (such as in many weight-training devices or weight machines) does not cause a high level co-activation of stabilising muscles. Functional tasks that require pushing or pulling an unstable ("live") load is a greater neuromuscular challenge than strength training exercises that rely on moving a stable, fixed load. 35 The difficulty in training muscles is that: 16C 5 1. many training devices predominantly require activation of the prime movers; 2. the stabilising muscles are only activated upon appropriate proprioceptive feedback; and 3. using many known devices does not provide the proprioceptive feedback 10 required for co-activation recruitment. Means for proprioceptive training The present invention provides a means for proprioceptive training, as part of strength and stability training. A Weighted Object(s) placed in the bag 20 or 15 secured directly to the Strap 30 place(s) a load on the muscles used to lift the device. The role of the Strap 30 is to destabilise the load, by introducing resistance perturbations (oscillations) when the load is moved. The user must apply a restoring force to maintain the load substantially in equilibrium while simultaneously moving the load. 20 Using the present invention to move the load involves: 1. activation of the prime mover muscles to perform the gross movement; 2. proprioceptive feedback from the movement; 3. co-activation of the stabilising muscles to stabilise the load and overcome 25 the resistance perturbations introduced by the Strap 30. Experiments conducted by the inventor found that users could be taught to "read" proprioceptive feedback during exercise training when using the present invention. Teaching this skill can be very difficult to achieve in practice, particularly in learning 30 or movement impaired individuals, which is particularly common in a rehabilitation setting. In practice, it is difficult to describe what the subject should be feeling when performing a particular movement and then to describe how that feeling should change in response to a different movement or how to perform a movement to change the proprioceptive feedback. 35 17C 5 Experiments conducted by the inventor showed that the present invention could be used for proprioceptive training, with particular advantage in learning impaired individuals for whom other forms of proprioceptive training are more difficult to teach. All subjects in the experiments, even those with learning impairment, were able to read the proprioceptive feedback and use it to co-actively engage 10 stabilising muscles during training. This is because proprioceptive feedback using the invention is perceived as the load "swinging" (oscillating) during movement of the load. The stabilising muscles are engaged by stopping the "swing". The "swing" is stopped by applying sufficient counterforce to the Handle to maintain the Weighted Object sustantially in equilibrium while using the device. 15 Means for training muscle co-contraction Training one or more muscle groups using unstable loads requires that the body appropriately responds to the task by producing force, reducing force and dynamically stabilising (applying a restoring force) against abnormal force. Co 20 ordinated muscle recruitment contributes to successfully support an unstable load. For the body to produce movement without the potential for injury, neuromuscular control needs to be sufficient for the body to produce movement around the right joint in the right plane and at the right time. These co-ordinated 25 movement patterns require the body not only to maintain appropriate forces but also to dynamically stabilise segments throughout the kinetic chain. Functional strength is the neuromuscular system's ability to produce force, reduce force and dynamically stabilise the kinetic chain during functional movements. 30 These movements need to be performed on demand in a co-ordinated smooth manner. Dynamic joint stability is achieved through the dynamic activation and co activation of specific muscles as the load changes. The stability of a muscle system 35 is trained and enhanced through the movement of an unstable load, since this 18C 5 mimics the requirements of functional movement that occur in everyday and sporting activities. Lifting an unstable load, or isotonically holding an unstable load, will challenge the body to mimic movement patterns that occur as part of real world (functional) 10 activities. Lifting a shopping bag out of the car, putting a suitcase on the top shelf of the wardrobe, or lifting a toddler out of the cot are everyday examples of lifting unstable loads. Means for training multi-planar movements 15 The present invention also provides a means for training multi-planar movements. The presentation of unstable resistances to specific muscle groups allows the muscle group to adapt to multi-planar resistances and respond with multi-planar movements, as are required in real world activities. 20 Traditionally both rehabilitation and strength training programmes focused on training isolated muscles groups in single planes of motion. However all functional activities are multiplanar and require acceleration, deceleration and dynamic stability of joints throughout the kinetic chain. Movement may appear to be in one plane but other planes will need to be dynamically stable for optimal movement to 25 occur. Training with an unstable load serves to improve neuromuscular control. Neuromuscular control is established by the combination of forces through the body occurring at the right joint, in the right plane and at the right time. 30 Training with an unstable load will force the neuromuscular system to respond at a higher level which mimics the response required to perform functional activities. The movement of unstable loads also serves to balance the varying external forces 35 by selectively shifting the stability of the muscle groups to enhance the user's 19C 5 posture in order to maximise efficiency of muscle forces whilst minimising passive tissue stresses In contrast, the movement of stable load tends to favour the isolation of specific muscles. Stable load shifting is common in rehabilitation and training regimes; 10 however, its benefits may be less optimal when compared to training with unstable loads. Consequently, training with unstable loads protects the user from skeleto-muscular injury and/or allows the user to successfully rehabilitate. Means for rehabilitation training 15 Neuromuscular control is required throughout the kinetic chain if movement patterns are to be optimal and the body is to remain injury-free. The neuromuscular system needs to remain efficient so it can cope with the demands placed on it during functional tasks. If the efficiency of the neuromuscular system 20 decreases the ability of the kinetic chain to maintain the appropriate forces and dynamic stabilisation significantly decreases. A decrease in neuromuscular efficiency leads to injury from compensation and substitution patterns as well as poor posture during functional activities. 25 The invention provides a means of training controlled functional movement patterns. This is key to the rehabilitation of injured or physically impaired individuals, as well as for training of optimal athletic performance and maintenance of general fitness and mobility or physical conditioning in the ageing population (e.g. baby boomers). Functional movement is integrated, multiplanar 30 movement that relies on acceleration, deceleration and stabilisation of the kinetic chain in a smooth and co-ordinated fashion. To successfully use the present invention, the user is required to dynamically stabilise through the kinetic chain while performing movements which require 35 deceleration and acceleration and stabilisation in multiples planes of movement. Jerky or uncontrolled movement patterns will become obvious to the user of this 20C 5 invention via proprioceptive feedback. The inventive device will be seen to swing or move if the user is not able to control movement throughout the kinetic chain. The section 'Means for proprioceptive training' (above) describes how the device assists in identifying and correcting faulty movement patterns. Experiments by the 10 inventor indicate that subjects who have difficulty in using, or are reluctant to use, free weights or other known weight-training equipment (e.g. the elderly or "mature-aged" individual, or the physically impaired) may find the inventive device relatively more comfortable and easier to use than known devices because of the easy scalability of the load (including the ability to adjust the load by adjusting the 15 lever (length of the Strap) rather than only by adjusting the weight of the load), and the clear proprioceptive feedback provided during use. Features of various embodiments of the inventive device 20 An elongate flexible member, or Strap Referring to the drawings, the Strap 30 enables the Weighted Object to perform as a "live" load, rather than as a constant or fixed ("dead") load. It acts as a secondary or tertiary lever (see below) but is flexible to enable resistance perturbations, 25 which are important in co-actively engaging the stabilising muscles and for training motor control. In the embodiments illustrated in Figures 2 to 5, the Strap 30 and Weighted Object are configured in a manner that concentrates the load to a single point. The Strap 30 30 acts as a central fulcrum; this causes further instability of the load. Experiments conducted by the inventor have indicated that the Distributed Load Embodiment is more comfortable in use in performing some exercises; however, all of the embodiments are capable of use in the desired manner. The Strap is configured so that relative wrapping between the Handle and the Strap (or flexible member) is 35 precluded and the length of the Strap remains unaltered during any rotation of the Handle. 21C 5 The Strap may be made from any suitable material, such as string, rope, cord or webbing for securing directly (see Figures 4 and 5) or indirectly (see Figures 1 to 3) to a Weighted Object for use in strength, stability and motor control training. Rubber cord (also described as exercise tubing, bungee cord or theraband) is also 10 suitable and adds additional instability to the load compared with materials with less elasticity (e.g. strong or rope). The Strap can be lengthened or shortened to: 1. increase or decrease the stability (oscillating movement) of the load; 15 and/or 2. change the lever characteristics. A cord lock, ladder lock, cam buckle, tension locking buckle, belay device or the like can be used to adjust the Strap. 20 A longer Strap will make the load more unstable and therefore more difficult to lift while maintaining it in equilibrium. Additionally a longer Strap will also increase the moment of inertia which will increase the relative mass of the load, again increasing the difficulty of the task. Unlike other fixed-weight strength training devices, lifting a weight that is not stable will challenge the neuromuscular system 25 and train the stabilising muscles of the body far more than a stable load. The flexible Strap makes the load unstable and therefore incorporates training to increase proprioceptive (sensory information) responses (and awareness) and increases activation of stabilisers. Improving recruitment of joint stabilisers can 30 lead to performance enhancement, motor control, strength gains and injury prevention. The flexible Strap also acts as a secondary or tertiary lever (the skeleton being the primary lever) since the Weighted Object (whether within a bag or secured directly 35 to the Strap) provides the resistance, and in the case of a: 22C 5 1. second-class lever, the lift on the Handle is the applied force. In this arrangement the force is more distal to the fulcrum (the pivot on which a lever moves) than the resistance - which is more proximal to the handle. Consequently, a small force can balance a larger weight. That is, the effective force is increased. Notice, however, that when a force moves the 10 Handle, the load moves more slowly and covers a shorter distance. An example is performing a push-up. 2. third-class lever, the speed and distance travelled by the load are increased at the expense of effective force (which moves a small distance). An example is a biceps curl. 15 The addition of levers with attached weights change: 1. the direction of an applied force on the muscle and/or surrounding muscles, and 2. the distance, speed and range of movement produced. 20 The Strap can be adjusted so as to work as a second or third class lever when lifting an unstable load, to work as many muscles as required across one or more joints (kinetic chain link model) rather than a single muscle across a single joint. Further, the Strap enables perturbations (oscillations) to be applied as an unstable resistance. 25 Increased proprioception awareness is achieved through use of embodiments of the invention through providing proprioceptive challenges for the limb(s) and trunk. This invention does not rely on the user's muscular effort to create the unstable environment (as it does using the Bodyblade or Wobble board) but relies 30 on gravity to create perturbations of the load - a situation which mimics real world movement patterns. In all of the embodiments, the Strap incorporates a Handle, being the part of the Strap where force is applied. The Handle may be completely seamless with the 35 Strap (see, for example, Figure 4B) or involve additional discrete components (see, 23C 5 for example, Figure 2). The Handle may be covered in foam or a tube (see Dictionary). In the case where the Handle is grasped by hand, one arrangement incorporates a foam cover or (or similar) or a tube for comfort and to facilitate rotation. Where the Handle is lifted by being hooked over the ankle, say, the tube is generally omitted. 10 An adjustable load The unstable load can be further adjusted by changing the Weighted Object. The Weighted Object comprises a weight-bearing object of a specified unit weight or multiples thereof. Adjusting the load can be achieved by: 15 1. detaching and attaching the Strap to a different Weighted Object (for example, compare Figures 4 and 5); or 2. substituting, adding or subtracting a Weighted Object placed in a bag attached to the Strap (e.g. in the embodiment in Figures 1, 2 or 3). 20 In the embodiments in Figures 1 to 3, the bag 20 is of a sufficient size to accommodate one or more Weighted Objects (such as dumbbells, or including infinitely adjustable materials such as sand or water). In one arrangement, the bag has approximately the equivalent volume of a standard shoe box (although it will not be limited in shape to a rectangular prism). 25 The bag 20 (see Figures 1 to 3) is made of any suitable material that can withstand the rigours of use as exercise equipment and of sufficient strength to carry the desired load. Examples of suitable materials include PVC, canvas, neoprene, hard wearing nylon fabric, polyester, polypropylene or similar. 30 The bag 20 has an opening to enable removal of contents and substitution of contents to vary the load. The advantages are: 1. weight can be added and removed as needed before use and/or during use; and 35 2. the invention is easily portable (the bag can be emptied and compacted to a minimal volume). 24C 5 If the user travels, the inventive device (with or without a bag) is light and can easily be packed into a travel case. Once at the destination, the Strap 30 can be attached to a suitable Weighted Object or the bag 20 can be filled to reach a specified unit weight by means ofa fluid filled bladder, sand or any other readily 10 available weighted item for the purpose of strength and stability training. The bag can be of any shape. Different exemplary arrangements in the shape of the bag include cylindrical, rectangular, square, round or flat as shown in Figure 6 with various configurations for Handles, Straps, loops and strings, as described 15 earlier. In the preferred embodiment, the bag is a rectangular prism, with greater proportional dimensions in length than in width or depth. Experiments by the inventor have found this shape to be advantageous over the other bag shapes as the narrow width of the bag enables the load to stay closer to the body while the length of the bag adds volume and allows a larger load to be carried. However, 20 experiments have also shown that other shapes are suitable for use and may be preferred depending on the specific training outcome desired. The embodiment in Figure 3 shows a closing means 50 comprising a light weight nylon or polyester fabric attached to the perimeter of the bag to contain/seal any 25 weighted items placed in the bag 20. A drawstring cord is sewn into the top of this fabric to secure all items in the bag. A cord lock secures the drawstring cord. This closing means 50 can be used in any embodiment wherein the load is provided by a Weighted Object placed within a bag. 30 An alternative arrangement of the closing means includes flaps positioned on opposing sides of the opening and closed by overlapping opposing edges then further secured with a buckle or the like (see Figure 1). This arrangement of the closing means allows the bag to extend in height (and 35 therefore volume) if necessary. The re-sealable closing means in any arrangement enables substitution, addition or removal of contents as desired. 25C 5 Weighted Object(s) In use, the load can be adjusted as desired. This has been described above. A variety of commonly available, inexpensive household items of a specified unit weight such as water in one or more sealed containers (see for example, Figure 5) 10 or a fillable bladder, or a container of sand, pebbles, flour, sugar filled to a specified unit weight can be used. Commonly available training equipment such as a dumbbell (see for example, Figure 4) can also be used. This provides flexibility for the user, since the user is not required to purchase, hire 15 or have access to a variety of commercially available weights (e.g. dumbbells) in order to work different muscle groups or perform different movement patterns. Adjusting the length of the lever (by adjusting the length of the Strap) enables a single Weighted Object to provide different loads. 20 This device can be used to perform standard strength training exercises such as: bicep curls, shoulder press, deltoid raise, bench press, tricep extension, single leg squat etc. Figures 6 and 7 show different embodiments being used to perform lateral raise (Figure 6A), front raise (Figure 6B), and leg squat (Figure 7A and B) exercises. The crucial element in using the device is stopping oscillations of the 25 Weighted Object and applying a restoring force while lifting or moving the device to maintain the Weighted Object in equilibrium (static). Method of stability training 30 Using the device The device is used by gripping the Strap at the Handle (i.e. the point where force is applied by lifting the Strap) or hooking the Strap over part of the arm or leg to lift the device. The device is lifted by the Handle while simultaneously applying a 35 restoring force through the Handle to stop oscillations of the Weighted Object, thereby maintaining the Weighted Object in an equilibrium (non-oscillating) 26C 5 position during use. Feedback is provided by the degree of "swing" or oscillations occurring. The device is designed so that the Handle does not interfere with proprioceptive feedback to the user. In one embodiment, the Handle is covered with a tube, which facilitates rotation of the Strap within the hand. 10 Standard weight-lifting exercises such as bicep curls, pec flyes, leg squats, lateral leg or arm raises and side raises, and side-lying hip abduction and adduction can be performed using the device. The difference with performing these exercises in the conventional manner is that the exercises are required to be performed using the preferred embodiment while applying a resisting force to the Handle. Shortening 15 the Strap (and/or strings) by adjusting its length enables the device to be used for squatting and lunging exercises where having a shortened lever enables a greater range of movement through the hips and legs before the Weighted Object touches the ground. 20 By adjusting the length of the Strap (and also the Strings, in the embodiments shown in Figures 2 and 3), the load can be varied without varying the Weighted Object. By providing a device for stability training, the present invention is valuable in the exercise rehabilitation and physical fitness setting. Research has shown that weak stabilising muscles of joints such as the back, shoulders and knees increases 25 the risk of injury to those joint. Both the general public and high level athletes have an increased potential for injury if the stabilizing muscles are not working optimally. The inventive device can be used in following settings: rehabilitation, yoga, tai-chi, 30 pilates, strength training, physical fitness or physical conditioning. The device can be used in a group or class setting with a teacher/instructor/therapist giving instruction and feedback. The invention can also be used in a one-on-one setting with a single client/patient and teacher/instructor/therapist giving instruction and feedback. The stabilising muscles are engaged by stopping or preventing the 35 "swing" while using the device, so that the Weighted Object is maintained substantially in equilibrium when lifting or moving the device. 27C 5 The inventive device is used in a slow controlled manner while performing various movement patterns that are performed traditionally in fitness, strength, conditioning or rehabilitation training routines. Examples of such exercises include bicep curls, lateral raise, front raise, shoulder press single leg squats, side lunges, 10 leg raise, and side-lying hip abduction and adduction. The invention can be used while the user is sitting, kneeling, lying or standing. Current weight training devices have a primary aim of strengthening the prime mover muscles such as the biceps for bicep curls, deltoids when performing 15 shoulder press, triceps when performing a tricep extension. This invention relies heavily on the kinetic chain link approach where control of one segment is necessary to transfer force to another segment. Kinetic chain activations should be encouraged as a means of developing efficiencies in force 20 development and joint protection. Dysfunction in the kinetic chain affects individuals involved in all levels of movement from the high-level athletic activities (such as gymnastics) to movements required for everyday living (such as walking). The invention has particular application to learning or mobility impaired individuals, including mature and elderly subjects, because of the enhanced 25 proprioceptive feedback provided using the device (e.g. the "swing") and the relative ease and comfort of use compared with known weight-training devices. Additionally this invention allows the user to change the relative load being lifted by adjusting the length of the Strap. For example, increasing the length of the Strap 30 increases the moment of inertia of the mass being lifting. No known devices enable users to adjust the load without changing the weight (mass) being lifted. Exemplary neuromuscular control training method When training to improve neuromuscular control, the goal is to start with 35 movements that provide the least challenge to the neuromuscular system and gradually progress these movement patterns to provide greater neuromuscular 28C 5 challenges. Exemplary training methodologies using the device are described below. 1. Wide base of support to narrow base of support Training begins by using the device while standing on both feet in a neutral stance 10 then progressing to a one-legged stance and finally to a dynamic single stance. 2. Single plane to multi-plane movements Movement of the device occurs through one of three planes sagittal, frontal, transverse or a combination of two or more planes. Training begins with a 15 movement that occurs in a single plane, such as a bicep curl, and progresses to a movement that occurs in more than one plane. As with any training programme the progression is from low weight and low repetitions to increasingly heavier weights with greater repetitions. 20 3. Varying body position The device can be used in any body position: supine, prone or side lying, sitting, kneeling or half kneeling, double leg standing, alternate leg standing, single leg standing. 25 4. Lower and upper extremity exercises The device can be used with single limb, two limbs (i.e. two arms or two legs), alternate upper and lower limbs (e.g. right arm , left leg), or single limb with rotation. One arrangement of the Distributed Load Embodiment enables the 30 device to be used with more than one person 5. Static to dynamic movement Training begins with the user remaining in a static position progressing to dynamic movements such as walking, lunges or squats while performing upper limb 35 movements. 29C 5 6. Balance modality Training can begin using the device while standing on the floor and progress to the following: sport beam, half foam roller, balance pad, balance cushion, balance board, wobble board, BOSU ball, prop shoes and sand. 10 7. Symmetrically loaded to asymmetrically loaded The user begins training by performing symmetrical movements firstly bilaterally then unilaterally. This progresses to movements which load one side of the body more or differently than the other side. For example, performing a side raise using the left arm while performing a front raise using the right arm. 15 8. Adjusting moment of inertia To provide a further challenge, the length of the adjustable Strap can be made longer which increases the moment of inertia and therefore the relative load being lifted. To begin training with this invention the Strap is kept short. As the user gains 20 control over lifting the unstable load, the Strap can be made longer. System for strength, stability and motor control training The present invention provides a system for strength, stability and motor control training, including: 25 1. an exercise device as hereinbefore described that enables the use of an unstable load in strength and stability training, with applications including: a. general fitness and conditioning; b. proprioceptive training; c. training muscle co-contraction; 30 d. training multi-planar movements; and e. rehabilitation training; and 2. exemplary methods for training including: a. movement patterns designed specifically for using the device (e.g. movements progressing from symmetrically loaded to 35 asymmetrically loaded, as described earlier in this document); 30C 5 b. using the exercise device in fitness, strength, conditioning or rehabilitation training routines (e.g. biceps curls) while keeping the Weighted Object of the exercise device in equilibrium ; c. combining use of the exercise device with tai chi, yoga or pilates techniques or other so-called "mind-body" fitness activities. 10 The inventive system can be used for individuals or in group settings for rehabilitation, strength training, physical fitness or physical conditioning as described earlier in this document. The inventive device can also be used in combination with yoga, tai-chi or pilates techniques to enhance the physical 15 benefits of these training techniques. Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied 20 in many different other forms. 31C