Patent Application
20250135275
This application claims the benefit of priority under 35 U.S.C. 119 to European Patent Application No. 23207069.8, filed Oct. 31, 2023; the disclosure of which is incorporated herein by reference in its entirety.
This invention relates to an abdominal roller, a training device for use in exercises to strengthen muscles, in particular abdominal muscles.
Abdominal rollers with a rolling arrangement connected to the center of a symmetric handle arrangement, allowing users to perform roll-out exercises to engage the abdominal muscles, are known. For a roll out exercise with a common abdominal roller the user usually kneels on a cushioned protective mat and holds the handle arrangement of the abdominal roller in both hands positioned vertically under the shoulders forming a bridge between hands and knees. During the roll out movement the hands are moved away from the knees extending the hips and shoulders to form a longer bridge between hands and knees. At full roll out the body of the user is substantially straight and the part of the body between hands and knees is hovering above the rolling surface without touching the rolling surface. The user will then perform a return movement from the full roll out position back to the base position in reverse order completing one exercise cycle of roll out and return movement. Less skilled users may perform alternatively a short roll out only extending the hips and keeping the hands substantially vertically under the shoulders and consequently less engaging the upper extremity musculature. Strong abdominal muscles are important for stabilizing the trunk and helping unload stress in the lumbar spine. Numerous abdominal exercises are used for abdominal strengthening, with or without commercially available training devices, in particular abdominal rollers.
Abdominal muscles (rectus abdominis, external oblique, internal oblique, and transverse abdominal) are commonly strengthened by actively flexing the trunk with a concentric muscle action (in particular crunch or sit-up), or by resisting trunk extension (due to an external force such as gravity) with an isometric or eccentric muscle action (in particular bridge or straight leg lowering).
Abdominal exercises that actively flex the trunk may be problematic for some people with lumbar disk pathologies because of increased intradiscal pressure and lumbar spine compression as well as people with osteoporosis because of the risk of vertebral compression fractures. Abdominal exercises that allow to maintain a healthy position by keeping a neutral spine and pelvis are therefore preferred.
Many of these exercises also activate extraneous (nonabdominal) muscles, such as the rectus femoris, erector spinae, or upper extremity musculature, which may or may not be beneficial. For example, high activation levels from the rectus femoris and erector spinae tend to generate a force couple that attempts to anteriorly rotate the pelvis and increase lumbar lordosis as well as to increase L4-L5 compression; when these conditions are coupled with weak abdominal musculature, the risk of low back pathologies increases. The lateral abdominal muscles (external oblique, internal oblique, and transverse abdominal) enhance spinal and pelvic stabilization and increase intra-abdominal pressure (IAP). IAP has been shown to unload the spine by generating a trunk extensor moment and tensile loading to the spine. The IAP mechanism makes the trunk a more solid cylinder resulting in a reduction in spinal axial compression and shear loads.
Studies have shown that roll out exercises, such as when using common abdominal rollers, yield the highest activation of the rectus abdominis muscle, and in lesser extent external oblique and internal oblique muscles. Studies have also shown that while performing these roll out exercises correctly, the abdominal musculature will primarily contract isometrically, and the pelvis and spine is stabilized and maintained in a beneficial neutral position throughout the roll-out and return movements.
Furthermore, studies have shown that roll out exercises advantageously minimize the activation of the lower extremity musculature, in particular rectus femoris and erector spinae. Studies have also shown that roll out exercises yield high activation of the upper extremity musculature, in particular pectoralis major, triceps brachii, and latissimus dorsi. These exercises may be beneficial for individuals with limited workout time and whose goal is to perform exercises that not only provide an abdominal workout but also an upper body workout. These exercises may not be warranted for individuals who have shoulder pathologies. Therefore, roll out exercise routines with abdominal rollers are preferred by users to strengthen their abdominal muscles, because of the high effectiveness on the abdominal muscles and the low risk of injury due to the neutral position of spine and pelvis during the roll out exercises.
Side-to-side differences in rectus abdominus size have been reported in users who engage in asymmetric sports, such as tennis, golf, and long jump. Side-to-side differences in the size of rectus abdominus are associated with the risk of strain injury. Attenuating a side-to-side difference in rectus abdominus size by doing asymmetric training may help to decrease the risk of strain injury.
Although common abdominal rollers advertise for an asymmetric exercise routine by allowing a curved roll out as a variation technique to the regular straight roll out, abdominal and oblique EMG activities measured during a curved roll out exercise were generally not different from a straight roll out exercise. Therefore, common abdominal rollers that allow curved roll out exercises are not proven to be effective to promote unilateral abdominal muscle development.
Common abdominal rollers with a narrow tread area on a single wheel, a spherical wheel or two wheels close to each other are typically designed to be instable to promote a higher activation of the abdominal muscles. The grip zones of both hands have substantially an equal distance to the tread area of the rolling arrangement and the user has to balance during roll out and return movement. The instability can increase the activation level of the abdominal muscles but also increases the risk of injury due to loss of control and hampers the untrained individual to fully engage in the exercise. The instable design furthermore dictates the user to equally divide its weight on both hands to prevent falling to one side and therefore only very limited promotes activation of the muscles unilaterally. The even distribution of the weight of the user on both hands hinder the unilateral engagement of the abdominal muscles.
It is an object of the invention to provide an advanced training device that obviates at least one of the abovementioned problems.
Thereto, the invention provides a training device for asymmetric training of abdominal muscles, comprising a handle arrangement, with a first grip zone for one hand of a user and a second grip zone for another hand of the same user, and a rolling arrangement, comprising a first end and a second end on a distance of each other along a roll axis, at least one approximate axisymmetric element allowing the rolling arrangement to have a rolling contact with a flat rolling surface at a tread area when the training device rolls during use under load over the flat rolling surface, wherein de tread area comprises a first tread edge with a first tread diameter near the first end, and a second tread edge with a second diameter near the second end, the handle arrangement rotatably connected to the rolling arrangement to rotate relative to the rolling arrangement about the roll axis, wherein, the first edge rotates approximately synchronized with the second tread edge and the first tread diameter is larger than the second tread diameter.
A rolling arrangement of a training device according to the invention may comprise of just one approximate axisymmetric element allowing the rolling arrangement to have a rolling contact with a flat rolling surface at a tread area when the training device rolls during use under load over the flat rolling surface. The tread area comprising a first tread edge near a first end of the rolling arrangement, and a second tread edge near a second end of the rolling arrangement. The first edge on the same approximate axisymmetric element as the second tread edge may rotate naturally synchronized with the second tread edge. A rolling arrangement of a training device according to the invention may comprise more than one approximate axisymmetric element. The approximate axisymmetric elements may be affixed directly or indirectly to each other in a way that the rolling arrangement in a rolling contact with a flat rolling surface during use under load only rotate substantially synchronized to each other as if it was only one approximate axisymmetric element.
The training device has a center point on the roll axis halfway between the first tread edge and the second tread edge. The center point may travel advantageously during roll out and return movement along a circular path as projected on the flat rolling surface, depending on the first tread diameter, the second tread diameter and the distance between the first tread edge and the second tread edge, resulting in a training device to target anterolateral abdominal muscles by enabling asymmetric roll out exercise routines.
By fixing approximate axisymmetric elements of a rolling arrangement to each other a rotation of the approximate axisymmetric elements relative to each other is prevented, even when forces or torques applied to the handle arrangement of the training device during roll out and return movement may not correspond with the circular path or when the traction of the rolling arrangement is unevenly distributed.
Fixing methods for fixing approximate axisymmetric elements to each other to rotate in unison, are known. A fixing method for example may be an interference fit when the hole of a wheel has a smaller diameter than the outside diameter of an axle. This way the wheel and the axle are substantially joint and held together by friction after the parts are pushed together. For example, two wheels fixed to the same axle using the aforementioned method may result in two wheels limited to rotate in unison depending on the forces applied on the wheels, therefor the wheels rotate approximately synchronized with each other. A fixing method may also be more rigid, for example use of bolts to secure a wheel to an axle to prevent any rotation of one wheel relative to the other wheel. Another example of a fixing method may be the use of one or more splines, or the use of a pen positioned in a hole perpendicular to the roll axis substantially through more than one element. Fixing the tread edges to each other and/or the wheels to each other can be done by one or more fixing elements or fixing means. The at least one fixing element is configured to rotationally fix the first tread edge and the second tread edge to each other so that they rotate in unison. The at least one fixing element can e.g., be an axle connected the first and the second tread edge, wherein the first and the second tread edge are rotationally fixedly mounted to the axle so that they rotate together with the axle. The at least one fixing element may also be embodied as a groove of an axle element in which the axisymmetric element can be press-fitted. The handling arrangement can be rotationally free connected to the rolling arrangement, e.g., to the axle, allowing the rolling arrangement to rotate while the handle arrangement is not.
The rolling arrangement has approximate axisymmetric elements with their axis of rotation aligned with the roll axis of the rolling arrangement and one or more approximate axisymmetric elements may contact a flat rolling surface when the rolling arrangement is rolled over the flat rolling surface under load. The rolling arrangement may have other elements that are not axisymmetric elements provided that these other elements do not substantially interfere with the rolling of the rolling arrangement. The training device rolls under load when a user performs an exercise routine with a roll out and return movement.
Approximate axisymmetric elements are known as elements with cylindrical symmetry that may have geometric irregularities. For example, a tire suitable for rolling may have a basic shape of an axisymmetric donut and additionally geometrically irregular grooves in the tread pattern, which don't interfere with rolling, and make the tire an approximately axisymmetric element.
The rolling arrangement has a circumferential tread area where the outer surface of one or more approximate axisymmetric elements is in contact with a flat rolling surface when the training device rolls during use under load over the flat rolling surface and the weight of the user may press the approximate axisymmetric elements into the flat rolling surface. The tread area may be one continuous segment on one approximate axisymmetric element, or a tread area may be divided over multiple tread segments on one or more approximate axisymmetric elements. An axisymmetric element can be a cylindrical element. In the following the terminology is used interchangeable. Other examples of axisymmetric elements are envisaged as well, e.g., ball shaped elements, or cone shaped elements.
The circumferential tread area may be visualized by rolling the training device over a flat rolling surface covered with colored ink. The circumferential tread area will become visible by transfer of the ink from the flat rolling surface onto the rolling arrangement. The circumferential tread area has a first tread edge closest to the first end of the roll axis with a first tread diameter and the circumferential tread area has a second tread edge closest to the second end of the roll axis with a second tread diameter.
The invention provides further a training device wherein the at least one approximate axisymmetric element comprises a first wheel and the rolling arrangement further comprising a further approximate axisymmetric element comprising a second wheel, wherein the first wheel comprises the first tread edge and the second wheel comprises the second tread edge. Further providing a training device wherein the rolling arrangement comprises a cylindrical axle element with a first axle end and a second axle end; and fixing means, wherein, the fixing means connect the first wheel to the first axle end and the second wheel to the second axle end to limit the wheels to rotate about the roll axis approximately in unison.
Particularly providing a training device wherein the fixing means rotationally fix the wheels to the cylindrical axle element.
By providing fixing elements to fixate each wheel to the cylindrical axle element a rotation of the wheels relative to each other is prevented, even when forces or torques applied to the handle arrangement of the training device during roll out and return movement may not correspond with the circular path or when the traction of the first wheel is different compared to the traction of the second wheel. Fixing elements to affix wheels to cylindrical elements, in particular a straight axle, limiting the first wheel and second wheel to rotate in unison. A fixing element for example could be the interference material when the hole of a wheel has a smaller diameter than the outside diameter of the cylindrical axle element to allow an interference fit. This way the wheels and the cylindrical axle element are substantially joint and held together by friction after the parts are pushed together. Fixing means could also be more rigid, for example bolts to secure the wheels to the cylindrical axle element. Another example of fixing means could be one or more splines on the cylindrical axle element, or a pen positioned in a hole perpendicular to the cylindrical axle element substantially through a wheel and the cylindrical axle element.
One hand of the user may be placed on the first grip zone and the other hand of the user may be placed on the second grip zone and the user may move the hands forward above the rolling surface away from the knees during roll out movement and return the hands towards the knees during return movement, completing one cycle of roll out and return movement.
The rolling arrangement rotates during roll out and return movement about the roll axis. During roll out and return movement the handle arrangement with the first grip zone and the second grip zone may freely rotate about the roll axis relative to the rolling arrangement in a way that the hands follow a smooth path maintaining approximately the same distance to the rolling surface.
Grip zones on handle arrangements are known. A grip zone on the handle arrangement may be an unmarked space that is obvious for a user to position a hand. The handle arrangement may consist of a cylindrical handle element with a suitable diameter and enough length to comfortably position two hands of the user next to each other freely rotating about the roll axis relative to the rolling arrangement, the handle arrangement may be commonly understood to comprise an unmarked first grip zone at one end of the cylindrical handle element and an unmarked second grip zone at the other end of the cylindrical handle element. The grip zones may be distinctly marked on the handle arrangement. The marking of the grip zones may be an outline, a color difference, a different shape or a different material. Each of these details provides particular advantageous and can be implemented independently of the other.
The training device may guide the user along the circular path during a roll-out and return movement, allowing the user to initiate via one hand a first force to the first grip zone and via the other hand a second force to the second grip zone. The first force may be seen as a first vector with a first initial point, a first magnitude and a first direction, and the second force may be seen as a second vector with a second initial point, a second magnitude and a second direction. The first initial point may be in the middle of the first grip zone and the second initial point may be in the middle of the second grip zone.
The first magnitude may be different from the second magnitude, and the first direction may be different from the second direction, while the center point of the training device advantageously continues to move substantially along the circular path projected on the flat rolling surface.
During roll out movement the first tread edge will travel further than the second tread edge, due to the difference in diameters between the tread edges. The first tread edge may advantageously move further away from the knees of the user than the second tread edge allowing for a guided asymmetric roll out exercise routine. The guided asymmetric roll out exercise routine enables the user to unilaterally train abdominal muscles effectively and safely.
A firsthand placed on the first grip zone closely positioned to the first tread edge may move further away from the knees of the user during the roll out movement than a second hand placed on the second grip zone closely positioned to the second tread edge, wherein the abdominal muscles at the side of the first hand may have a higher activation level than the abdominal muscles at the side of the second hand. The arm of the user at the side of the second hand may not be fully stretched and the muscles at the side of the second hand may be less activated. Therefor the user may use the second hand on the lesser engaged side of the body to actively steer and control the roll out and return movement of the training device.
The arm of the user connected to the first hand may be called an extended arm and the arm of the user connected to the second hand may be called a controlling arm. The user may target the abdominal muscles at the side of the body with the extended arm more severely by increasing the weight of the body directed to the first hand. Advantageously the abdominal muscles on the side of the extended arm are trained with a higher load. The second hand of the controlling arm may consequently endure less weight of the body. Advantageously the controlling arm will be even less activated and may be able to steer, support and control the exercise even better. The user may perform a tilted roll out routine and rotate the lower body about the longitudinal axis of the body and lower the hip at the side of the extended arm, resulting in the body of the user closer to the rolling surface at the side of the extended arm over the full length of the body. The user may perform a twisted roll out routine and lower the hip at the side of the controlling arm resulting in a twisted body at full roll out position when contralaterally the shoulder of the extended arm will also move towards the rolling surface.
The user may lift one leg during roll-out and return movement. The stability of the training device with the first tread edge distant from the second tread edge advantageously provides enough stability for the user to only rest on one knee and lift the other leg up from the rolling surface without falling. In this exercise routine the leg that is in contact with the rolling surface carries much weight of the body and may be called the supporting leg. The lateral abdominal muscles are activated to remain lumbar torsion control by keeping the pelvis and rib cage locked and prevent the lifted leg from dropping during roll out and return movement. The supporting leg may be unilaterally to the extended arm.
The user may alternatively have the supporting leg contralaterally to the extended arm. Advantageously these unique asymmetric exercises with the advanced training device involves resisting trunk rotation and extension through isometric or eccentric muscle contraction by keeping a neutral and safe spine and pelvis posture. It is noted that the unique and advantageous exercise routines described are exemplary asymmetric roll out exercise routines possible with embodiments of the invention. The exercise routines are given by way of non-limiting examples.
Hereinafter, the effectiveness of muscle activation by the present invention will be specifically described with reference to one test example, but the present invention is not limited to this test example at all. Every user will perform exercise routines with the training device according to the invention differently and measurements may show different activation levels and lateral variations.
The used test equipment is commercially available. Relevant testing methods and specific operation manners of related instruments used in tests are all well-known to the skilled in the art.
A well-trained male user, aged 23 years old, has tested a training device according to the invention with a first wheel with a diameter of 145 mm and a second wheel with a diameter of 100 mm. The wheels with a distance of 600 mm apart fixed to an axle and a handle arrangement with a first grip zone and a second grip zone rotating about the axle between the first wheel and the second wheel. For reference the user also tested existing abdominal exercises, in particular crunch and side plank with hip dip without tools and a straight roll-out and curved roll-out exercises with a standard available abdominal wheel called AB WHEEL of the brand Domyos by Decathlon.
The user was monitored with Electromyography (EMG) analysis equipment, including wireless Mini Wave electrodes by Cometa srl and EMG and Motion Tools software version 7.0.
The following eight muscles of the user were monitored:
The user performed three maximal voluntary contraction (MVC) exercises before the test round and repeated the three MVC exercises after the test round. One MVC exercise for the lower and upper rectus abdominus, one MVC exercise for the left external oblique and the left internal oblique and one MVC exercise for the right external oblique and the right internal oblique.
Five exercises were conducted with the training device according to the invention.
A basic roll out as depicted in
All exercises were conducted one time with the large wheel near the left hand and one time with the large wheel near the right hand.
As reference four common exercises were conducted: crunch, straight roll out with the AB WHEEL, curved roll out to left and right with the AB WHEEL and side bridge with hip dip left and right.
All exercises were conducted with a pause in the extreme position where an average isometric activation level of the muscles was measured. The average values of the isometric phase are listed in the following table as a percentage of the MVC levels.
The following conclusions can be drawn from the test results. The reference exercises show either strong unilateral activation with low activation level, like the side bridge with hip dip, or activation at a high level with only limited lateral variation in muscle activation, like the curved roll out with the AB WHEEL. It is also noted that the symmetric reference exercises like crunch and the straight roll out with the AB WHEEL show some unintended uneven distribution of activation levels between left and right, probably because of an unconscious preference of the user or due to compensation of instability.
Several exercises with the training device according to the invention activate the muscles advantageously at a high level and unilaterally at the same time. The basic roll out with the stable training device according to the invention has only slightly lower muscle activation compared to the roll out exercises with the instable AB WHEEL. Advantageously the unilateral variations in the exercise routines increase activation levels and add lateral differences in muscle activation. The tilted roll out exercise shows reduced activation levels of the lower and upper rectus abdominus but has very high unilateral activation of the external oblique muscles, which makes the exercise very suitable for targeted training of the external oblique muscles unilaterally. The twisted roll out unilaterally targets all the muscles at a very high level making it very suitable for unilateral training of an advanced athlete. The leg lifted roll out exercises have an even higher activation of all muscles, far beyond the level that is provided with the conventional AB WHEEL without introducing uncomfortable instability or jeopardizing the safety of the spine by keeping the spine in a neutral position, making it even more suitable for professional athletes.
Therefore, the training device according to the invention uniquely provides in a simple tool to safely and comfortably perform a variety of asymmetric abdominal exercise routines to target different abdominal muscles unilaterally and highly effectively in a way that is unprecedented.
The invention provides a training device preferably wherein the first grip zone is substantially closer to the first tread edge than the second grip zone and the second grip zone is substantially closer to the second tread edge than the first grip zone. During a unilateral exercise a first magnitude of a first force of a firsthand of the extended arm may be larger than a second magnitude of a second force of a second hand of the controlling arm. The first grip zone substantially closer to the first tread edge than the second grip zone may secure the stability and safety of the training device. The distance between a first initial point of the first force and the first tread edge may be shorter than the distance between a second initial point of the second force and the first tread edge. An initial point of a combined force of a first vector of the first force added to a second vector of the second force may advantageously be located between the first tread edge and the second tread edge, therefore the training device will remain stable on two wheels even when the first magnitude of the first force becomes substantially larger than the second magnitude of the second force.
The invention provides a training device with a first initial point in the middle of the first grip zone and a second initial point in the middle of the second grip zone preferably wherein the distance between the first initial point and the first tread edge is less than 80% of the distance between the second initial point and the first tread edge, in particular less than 65%, more particular less than 50%.
In particular a training device wherein the distance between the second initial point and the second tread edge is less than 80% of the distance between the first initial point and the second tread edge, in particular less than 65%, more particular less than 50%, to provide stability during the roll out and return movement even when the second magnitude of the second force becomes substantially larger than the first magnitude of the first force.
The invention provides a training device wherein the first grip zone and the second grip zone are positioned between the first tread edge and the second tread edge. The training device may have a simple design and an unevenly distribution of the weight between the first grip zone and the second grip zone may not lead to tipping over of the training device.
The invention provides a training device wherein the handle arrangement comprises a cylindrical handle element wherein, the cylindrical handle element comprises the first grip zone and the second grip zone. The first grip zone and the second grip zone advantageously always rotate synchronized with each other. The invention provides a training device comprising a handle arrangement consisting of a first cylindrical handle element with the first grip zone and a second cylindrical handle element with the second grip zone wherein, the first cylindrical handle element and the second cylindrical handle element rotate relative to each other. The first element and the second element may rotate separately about the roll axis and independent of each other, wherein both hands may find their own neutral position.
An element of the handle arrangement with the first grip zone or the second grip zone may be freely rotating about the roll axis positioned outside the rolling arrangement. A cylindrical handle element may be positioned in a central hole through the rolling arrangement with the first grip zone at one side of the rolling arrangement and the second grip zone at the other side of the rolling arrangement.
The invention provides a training device comprising a first axisymmetric element made of metal and a second axisymmetric element made of plastic, e.g., cylindrical elements, one of said first and second axisymmetric elements being part of the rolling arrangement and the other of said first and second axisymmetric elements being part of the handle arrangement wherein, the metal element is positioned inside the plastic element to form a revolute joint.
The cylindrical handle element may advantageously be of a strong material, in particular metal, and may be installed through the cylindrical axle element, made of a low friction material, in particular plastic, to form a revolute joint. The cylindrical axle element may advantageously be of a strong material, in particular metal, and may be installed through the cylindrical handle element, made of a low friction material, in particular plastic, to form a revolute joint. Furthermore, the metal may be steel and optionally a protective zinc coating, chrome coating or plastic coating is applied to the metal cylindrical element. The coating reduces the friction and makes the metal cylindrical element suitable for smooth rotating in cylindrical contact with the plastic cylindrical element. Plastic generally is a low friction material relative to metal, in particular nylon, HDPE or PP. By having the inner diameter of the plastic cylindrical element larger than the outer diameter of the metal cylindrical element, the plastic cylindrical element is enabled to rotate freely around the metal cylindrical element in a revolute joint. A plastic cylindrical element is easy to produce and provides a strong and lightweight component of the training device. Furthermore, it is noted that the friction can advantageously be reduced by many other means known, in particular lubrication or a geometry with ridges that reduces the contact area between the sliding surfaces.
Each of these details provides particular advantageous and can be implemented independently of the other.
The marking of the grip zones may be a soft cushioning made of EVA foam or rubber for more comfort. The grip zones may be designed in an ergonomically optimal shape. Furthermore, the grip zones may be of a thermoplastic material ergonomically shaped for optimal comfort. The grip zones may be reflection symmetrical in a plane through the roll axis to provide the same optimal ergonomic support when holding the first grip zone in the left hand and the second grip zone in the right hand as when holding the first grip zone in the right hand and the second grip zone in the left hand. The first grip zone may have a fundamental different design than the second grip zone whereas the hand on the first grip zone may have a different angle to the roll axis than the angle to the roll axis of the hand on the second grip zone.
In exercise routines during roll out movement abduction may occur for the first hand and adduction may occur for the second hand. It may be advantageous to give the first grip zone and the second grip zone an ergonomic shape that may allow the inward and outward movements of the hands and prevent injury. The invention provides a training device wherein the handle arrangement comprises a support handle approximately perpendicular to the roll axis. By having for example, a support handle connected to the first grip zone at the position of the thumb approximately perpendicular to the roll axis the thumb of the first hand may curl around the support handle and the first hand may conveniently need to adduct less in a full roll out position.
The training device may have specific dimensions that provide particular advantageous for users. The center point of the training device may move approximately along a circular path as projected on the flat rolling surface with a radius defined by the first tread diameter, the second tread diameter and the distance between the first tread edge and the second tread edge. Longer users may need a training device moving along a circular path with a larger radius and shorter users may need a training device moving along a circular path with a smaller radius. One exercise routine may be a full roll out where a larger radius is preferred, another exercise routine may only be a short roll out where a smaller radius is preferred.
The invention provides a training device comprising a center point, the center point traveling along a circular path projected on the flat rolling surface with a radius when the training device rolls during use under load over a flat rolling surface, preferably wherein, the radius is between 80 cm and 500 cm, in particular between 120 cm and 300 cm, more particular between 140 cm and 250 cm.
The invention provides a training device comprising a distance between the first tread edge and the second tread edge, preferably wherein the distance is more than 7 cm, in particular more than 14 cm, more particular more than 20 cm.
It may be advantageous for the user to have the first grip zone and the second grip zone approximately at the same distance as the biacromial shoulder width of a user. It may be advantageous when the first grip zone and the second grip zone are positioned between the first tread edge and the second tread edge. A training device with a large distance between the first tread edge and the second tread edge may also be advantageous for more flexibility in exercise routines. The invention provides a training device preferably wherein the distance between the first tread edge and the second tread edge is about 20 cm to about 120 cm, in particular about 30 cm to about 90 cm, more particular about 40 cm to about 80 cm, even more particular about 50 cm to about 70 cm. It is noted that the training device may for instance be preferred to be stored in small places, in particular in a suitcase for traveling. A short distance between the first tread edge and the second tread edge may also be advantageous because the load on the cylindrical elements may be lower. Short cylindrical elements may less likely bend or break than long cylindrical elements. The invention provides a training device preferably wherein the distance between the first tread edge and the second tread edge is less than 80 cm, in particular less than 60 cm, more particular less than 40 cm.
This may be advantageous to provide for a stable training device when the rolling arrangement is positioned between the first grip zone and the second grip zone.
A training device may advantageously be disassembled and assembled by the user for easy storage.
The invention provides a training device preferably wherein the first tread diameter is between 5% and 100% larger than the second tread diameter, in particular between 20% and 80% larger, more particular between 35% and 65% larger. This may be advantageous for a training device for users of various length.
The invention provides a training device preferably wherein the second tread diameter is larger than 7 cm. So that advantageously the hands do not touch the rolling surface during exercise. A compact training device is preferred for easy carrying and storage.
Furthermore, the invention provides a training device preferably wherein the first tread diameter is smaller than 50 cm, in particular smaller than 35 cm, more particular smaller than 25 cm. Nevertheless, larger wheels can be advantageous for exercise routines more elevated from the floor or on particular rolling surfaces, in particular on loose sand or uneven rolling surface.
The invention provides a training device wherein the wheels have tires. Advantageously to enable better performance by providing a flexible cushion that absorbs shock and keep a strong grip of the wheel to the rolling surface.
Furthermore, the invention provides a training device wherein the tire is made of high-friction material. High-friction material further increases the grip of the wheels to the rolling surface during roll out and return movement, which may be advantageous when the training device is used on a smooth and dry rolling surface. Advantageously the invention provides a training device wherein the high-friction material contains rubber (e.g., PU). By preventing slipping of the wheels relative to the rolling surface the training device will better follow the circular path and less deviate from the circular path by slipping. The user may be able to differentiate the first force more from the second force and therefore experience more control and may be more effective in targeting specific abdominal muscles unilaterally. By applying the first magnitude substantially different from the second magnitude or applying the first direction substantially different from the second direction while the center point of the training device stays substantially on its circular path, the user may target specific muscles unilaterally and more effectively.
The tire may be molded directly on the wheel. The tire may be made of a different material than the wheel. The invention provides a training device wherein the tire has a high-friction tread. High friction tread increases the grip of the wheels to the rolling surface. The invention provides a training device wherein the tread on the wheel has a tread pattern. A tread pattern may be advantageous when the training device is used on a soft or loose rolling surface. Other tread patterns may be advantageous on rough or wet rolling surfaces. Each of these details provides particular advantageous and can be implemented independently of the other or in combination with each other.
The training device may have a spring mechanism that connects the rolling arrangement to the handle arrangement. When the training device is rolled out, the spring mechanism may wind up and towards the end of the roll out the user is supported by an increased pull back force of the spring. The pull-back force during the travel of the roll out is stored as energy in the spring. This stored energy in the spring may be released during the return movement and support the user. This way the user may be aided to perform a roll out exercise and the spring mechanism may prevent an uncontrolled roll out and return movement.
Further advantageous embodiments are in the dependent claims.
With reference to the exemplary embodiments shown in the drawings the invention will now be specified, although only by way of example. In the drawings:
It is noted that the drawings are only diagrammatic and schematic representations of exemplary embodiments of the invention. The embodiments are given by way of non-limiting examples. In the figures, the same or corresponding parts are represented with the same reference numerals.
The circumferential tread area 24 has a first tread edge 251 closest to the first end 201 of the rolling arrangement 2 with a first tread diameter and the circumferential tread area 24 has a second tread edge 252 closest to the second end 202 of the rolling arrangement 2 with a second tread diameter.
The first tread diameter of the first tread edge 251 being larger than the second tread diameter of the second tread edge 252.
The wheels 26 are made of polypropylene and have a tire 27 made of PU rubber molded directly on the wheel 26. The fixing means 29 for connecting the wheels 26 to the cylindrical axle element 53 are cylindrical plugs made of nylon with splines in longitudinal direction pressed through the hole of the wheel 26 and through the inside of the cylindrical axle element 53 creating an interference fit.
The user may choose to place the first hand on the first cylindrical handle element 531 close to a first wheel 261, being a first grip zone 511. The user may choose to place the second hand on the first cylindrical handle element 531 close to a second wheel 262, being a first alternative for a second grip zone 5121. Or the user may choose to place the second hand on the second cylindrical handle element 532, being a second alternative for a second grip zone 5122. The first grip zone 511 is substantially closer to the first wheel 261 than the second grip zone 5121, 5122 and the second grip zone 5121, 5122 is substantially closer to the second wheel 262 than the first grip zone 511.
In
In
The user may choose to place a firsthand on a first cylindrical handle element 531 close to the first wheel 261, being a first alternative for a first grip zone 5111. Or the user may choose to place the first hand on a second cylindrical handle element 532 close to the first wheel 261, being a second alternative for a first grip zone 5112. The user may choose to place a second hand on the second cylindrical handle element 532 close to the second wheel 2622, being a second grip zone 5122. The first grip zones 5111, 5112 are substantially closer to the first wheel 261 than the second grip zone 5122 and the second grip zone 5122 is substantially closer to the second wheel 2622 than the first grip zones 5111, 5112.
During roll out movement a firsthand 61 placed on a first grip zone 511 positioned close to the first wheel 261 advantageously moves further away from the knees of the user than the second hand 62 placed on a second grip zone 512 positioned close to the second wheel 262 allowing for a guided asymmetric roll out exercise routine. In
During roll out movement the first wheel 261 travels further away from the knees of the user 6 than the second wheel 262 allowing for the user to lift the left shoulder 68 by extending the controlling arm 64, resulting in the body of the user 6 to be closer to the rolling surface at the side of the extended arm 63 advantageously over the full length of the body to target the lateral abdominal muscles even more effectively.
The first grip zone 511 has a fundamental different design than the second grip zone 512, whereas in full roll out position the hand on the first grip zone 511 has a different angle to the roll axis 3 due to abduction than the angle to the roll axis 3 of the hand on the second grip zone 512 due to adduction.
The first grip zone 511 includes a support handle 5111 at the position of the thumb approximately perpendicular to the roll axis 3. Advantageously the thumb of the first hand can curl around the support handle 5111 and the first hand conveniently can adduct less in a full roll out position.
| Number | Date | Country | Kind |
|---|---|---|---|
| 23207069.8 | Oct 2023 | EP | regional |
