Abstract: A weight stack isolator comprises an impact damper having a rail void therein configured to receive a guide rail of a selectorized machine. The impact damper is shaped to at least partially surround a section of the guide rail when received in the rail void, to secure the weight stack isolator to the selectorized machine. The weight stack isolator may include a slit extending from its outer perimeter to the rail void or the rail void may extend to the outer perimeter, to removably receive the guide rail in the rail void. The weight stack isolator can be positioned under a weight stack of the selectorized machine to absorb or dampen noise and vibration.

Abstract: The therapeutic isometric testing and isotonic training exercise device disclosed herein may allow for isometric strength testing and isometric and isotonic strength training of a user to prevent or treat soft and connective tissue deficiencies. The device may comprise, generally, a leg press, chest press, and shrug press exercise device combination having a plurality of electronic components. The device may comprise a seat assembly and weight stack assembly connected to an articulating frame, and may further comprise a weight locking pin and a plurality of load sensors for user work measurements. A proprietary software may be integrated into the device, and each user may have a personal user account and customized training regimen designed for them based on system inputs and readings.

Abstract: An exercise apparatus that is configured to be operably coupled to a conventional support frame having support poles providing vertical movement of the exercise apparatus. The exercise apparatus includes a bar member wherein the bar member has an engagement portion for use by a user when executing an exercise using the bar member. The engagement portion is provided in alternate styles. The bar member includes a pair of bar support members that are opposedly located on the bar member at opposite ends of the engagement portion. The exercise apparatus further includes a first connection assembly and a second connection assembly that are configured to operably couple with the first bar support member and second bar support member. Pin assemblies are provided to releasably secure the first bar support member and second bar support member with the first connection assembly and second connection assembly.

Abstract: A modular and dynamic force apparatus for adjusting standard and dynamic torque-to-linear forces during physical activity in real-time, the apparatus including a force module, a user device and an apparatus tracking processing unit. The force module includes an open hub attachment point, wherein the open hub attaches the apparatus to an external source, one or more sensors measuring data for physical activity efficiency, an internal processor, wireless radio and force sensor module, a variable length cable, a force generating component, and motor controls. The internal processor, wireless radio and force sensor module includes an apparatus tracking measurement unit (“ATMU”) adapted to measure data, a first electronic communications channel for transmitting the measured data to an apparatus tracking processing unit (“ATPU”), and a second electronic communications channel for transmitting one or more apparatus conditions data to adjust dynamic forces.

Abstract: Fitness equipment (1), in particular for the assisted performance of press-ups, comprising a support device (2) having a movable support (3) on which a user rests during use, and an assistance device (4) that is configured for generating an assistance force that moves the support (3) into an initial position, wherein the assistance device (4) is or comprises a traction device which is configured to generate an assistance force on the support (3) that moves the support (3) into the initial position and acts as a tensile force.

Abstract: An exercise machine. The machine includes a frame with front and rear upper support beams. Guide rails span between the two support beams and are connected thereto. Right and left handles are configured to slide back and forth along the length of the guide rails between the front and rear support beams. During operation of the machine, a user grabs the handles and moves them back and forth in a swinging motion that mimics traversing a set of monkey bars. The guide rails may be arranged in a non-parallel configuration to provide a more natural path for the user's hands during operation and to reduce unwanted stress on the user's shoulders by limiting handle movement along the path to accommodate a more comfortable range of motion.

Abstract: A weight resistance training machine is provided that is used to exercise the glute muscles of a user. The weight resistance training machine includes a carriage member that a user may mount to use the training machine. The carriage member may be mounted on a track system that allows the carriage member to translate linearly when the weight training machine is used. When a foot press bar connected to the carriage member is extended, the carriage member is linear translated by a cable and pulley system to increase the muscle path length during exercise and increase the exercise's efficacy.

Abstract: A weight stack isolator comprises an impact damper having a rail void therein configured to receive a guide rail of a selectorized machine. The impact damper is shaped to at least partially surround a section of the guide rail when received in the rail void, to secure the weight stack isolator to the selectorized machine. The weight stack isolator may include a slit extending from its outer perimeter to the rail void or the rail void may extend to the outer perimeter, to removably receive the guide rail in the rail void. The weight stack isolator can be positioned under a weight stack of the selectorized machine to absorb or dampen noise and vibration.

Abstract: A device for logging exercise data, the device includes a body for engaging with an exercise machine; an electrical system with a power source incorporated into the body and to record data; an image sensor incorporated into the body and to capture an image; a motion sensor incorporated into the body and to detect movement; the image sensor determines a weight load associated with the exercise machine; the motion sensor detects and records a number of repetitions of movement; and the device creates an exercise log associated with a user's workout.

Abstract: A system comprising an exercise system having a resistance structure of an exercise bar connected to cables, which cables are connected to at least one pneumatic cylinder that creates resistance, wherein the resistance is adjusted by the user via actuators in the exercise bar, so that the user does not need to release the exercise bar to adjust the resistance. The system may be supported by a frame, and the pneumatic cylinder may be connected to an equalizing tank that may be housed within or integrated into the frame. The system may include a monitor to visually display system parameters and other information to the user. The system may calculate resistance and work done by the user by measuring piston displacement and speed, as well as using accelerometers or other devices integrated into the exercise bar.

Abstract: A rectangular frame for a reformer exercise apparatus is disclosed which includes a pair of spaced apart side rail members, a head end member, a foot end member; and four corner members, each joining one of the side rail members to one of the end members. Each side rail member and each end member is a rigid generally rectangular extrusion. The top wall, the bottom wall and the inner vertical wall have interior screw races. The outer vertical wall has a pair of spaced interior projecting screw races. Each corner member is fastened to one of the end members and one of the side members by threaded fasteners projecting from the screw races through apertures in the L shaped elongated corner member, and an L shaped cover hides these fasteners from view.

Abstract: Sensor data is collected from a sensor monitoring a tension generating device of an exercise machine. The sensor data is analyzed to determine whether the sensor data is within a specification. In the event the sensor data is not within the specification, an error stop mode is entered for the tension generating device.

Abstract: A magnetic control exerciser includes a base, a pulley device and damping device respectively disposed on the base. A first rope is coiled on the pulley device, wherein a first handlebar and a second handlebar are respectively transversally connected to a first end and a second end of the first rope. A second rope has two opposite ends respectively connected to the pulley device and the damping device for providing a damping and promoting the effect of the magnetic control exerciser in accordance with the present invention. The first handlebar has an original horizontal height higher than that of the second handlebar for providing different exercising modes. A seat is secured on the base for user to easily operate the first handlebar and the second handlebar.

Abstract: A system and method of using an exercise system having a resistance structure of handles connected to cables, which cables are connected to at least one pneumatic cylinder that creates resistance, wherein the resistance is adjusted by the user via actuators in the handles, so that the user does not need to release the handles to adjust the resistance. The system is typically supported by a frame to surround the user, and the pneumatic cylinder may be connected to an equalizing tank that may be housed within or integrated into the frame. The system may include a monitor to visually display system parameters and other information to the user. The system may calculate resistance and work done by the user by measuring piston displacement and speed, as well as using accelerometers or other devices integrated into the handles.

Abstract: The present invention provides an active and passive exercise training equipment comprising a swinging device, a supporting device, and a front supporting device. The swinging device comprises a seat cushion with moving function for a user to sit. The supporting device comprises a telescopic rack and a top rack for the user to grip. The top rack is set on the telescopic rack for being located at different heights. The front supporting device comprises a front telescopic rack and a front grip for the user to bend forward to grip. The grip is set on the front telescopic rack for being located at different horizontal distances and vertical heights. The height and the distance can be adjusted according to the stature or requirement of the user so that the user can train his muscular strength efficiently and also make his body to achieve a relaxed state.

Abstract: A back exercise machine includes: a resistance element; a user support; a first movement element, the first movement element having: a column; and a first connecting element having a pivot point such that the user support is able to pivot about a first axis associated with the first connecting element, wherein the first connecting element is movably coupled to the column such that the first connecting element is able to move along a path defined by the column; and a second movement element, the second movement element having: a rail; and a second connecting element having a pivot point such that the user support is able to pivot about a second axis associated with the second connecting element, wherein the second connecting element is movably coupled to the rail such that the second connecting element is able to move along a path defined by the rail.

Abstract: A squat exercise apparatus may comprise a support structure, a user adjustable resistance source and lift arms supported by the support structure and operably coupled to the user adjustable resistance source. In one implementation, the lift arms may be pivotable relative to the support structure about three orthogonal axes. In one implementation, shoulder pads carried by the lift arms may automatically pivot in response to pivoting of the lift arms relative to the support structure. In one implementation, at least one weight movement arm may have an adjustable length. In one implementation, a weight movement arm rest may be pivotable between a weight movement arm engaging position and a retracted position, wherein interacting portions of the weight movement arm rest and the weight movement arm are magnetically attracted to one another to magnetically retain the weight movement arm rest in the weight movement arm engaging position.

Abstract: The exercise machine in the present disclosure utilizes novel machine mechanics that accommodate and adjust to the spines shifting axis of rotation. Through the use of a multiple, articulating axes a back exercise machine or device that promotes pure and isolated spinal flexion and extension with no need for mechanical anatomical restraint to succeed has been created. Using these mechanics when users attempt to extend their trunk, the device adjusts to the natural shifting axis of rotation of the spine thereby dis-involving the contribution of the hip extensor muscles. In other works, the exercise back machine of the present disclosure is designed to accommodate the complex biomechanics of the spine and to facilitate targeted strengthening of the spinal erectors and deep intrinsic spinal muscles.

Abstract: A physical exercise apparatus includes a frame, a seat, an arm, and a pair of cycling hand pedals. The seat is supported by the frame and is configured to support a user in an at least partially supine position. The arm is movably attached to a first portion of the frame and coupled with a linearly movable resistance load. The pair of cycling hand pedals is attached to a second portion of the frame and is independently movable from the arm so that the user can cycle the pair of cycling hand pedals while separately moving the arm with a portion of his or her lower body.

Abstract: A device is used for carrying out movements by shifting the center of gravity and/or actuating muscles of a human body. A user lies on the device and shifts the center of gravity by moving his or her hip region in order to incline a movable part of the device including the user's own body in different directions. Furthermore, the user wears video goggles or the like during the process and can move in a virtual environment using the overall system, which includes the video goggles and the movement device and can interact with these. The movements caused by the user can be generated solely using gravity by shifting the center of gravity. Additionally, the movements of the device are influenced by motors or dampers arranged in or on the device.

Abstract: This invention is a portable exercise system capable of performing multiple exercises for strength and endurance training. The key component is the force generation unit (FGU) which is small and light enough to be suspended during the exercise yet capable of producing a force of 50 lbs. The FGU is programmable allowing it to generate various force vs distance, time or velocity profiles. Different handles, cables and attachments can be connected or used with the FGU perform different exercises. The FGU can charge its battery from the user's energy during use. The FGU can communicate bidirectionally with computers and smart phones for setup and to track the user's performance. Multiple FGUs may be used simultaneously each performing a separate function. The entire system is small enough to fit in a drawer or suitcase. The accompanying software can track the user's performance and function as an automated personal trainer.

Abstract: A weightlifting apparatus having free weight simulation and a safety mechanism includes at least one upright support having a bar engaging pulley assembly and a weight engaging pulley assembly. The upright support includes a universal joint for allowing the upright support to pivot. A lifting bar having an end movably coupled to the bar engaging pulley assembly is also included. The lifting bar includes a grip portion having switch contact disposed therein that is engaged when the grip portion is depressed. A clutch assembly is provided for enabling the bar engaging pulley assembly and weight engaging pulley assembly to move together in unison when a voltage is supplied by engaging the grip portion. Disengagement of the grip portion opens the switch contact and causes voltage to be cut off from the clutch assembly, thereby disengaging the weight support element and the lifting bar.

Abstract: A chest exercise machine includes: a resistance element; a user support coupled to the resistance element; a first movement element coupled to the user support; and a second movement element coupled to the user support. A chest press machine includes: a cable resistance element adapted to allow for a resistance path that is at least partly defined by a user; a user support adapted to move along a movement path as a chest press is performed; and a load including a set of plates that may be selectively coupled to the cable resistance element. A pectoral fly machine includes: a cable resistance element adapted to allow for a resistance path that is at least partly defined by a user; a user support adapted to move along a movement path as a pectoral fly is performed; and a load including a set of plates.

Abstract: A polyvalent apparatus for physical therapy including a support to which is fastened a first tool provided for a specific treatment, a second and a third tool provided for a specific treatment, the second and the third tool being connected to the support in combination with the first tool.

Abstract: A gymnastic machine having a frame defining a support area for the back of a user and a platform for the support of the feet, where the support area and the platform are inclined on opposite sides with respect to the vertical and are mutually convergent downwards. A work unit is associated with the frame and has a loading unit for the execution of a gymnastic exercise and movement means for moving the loading unit. The work unit has a bearing element associated with the frame and the movement means has a grip element which can be gripped by the user, the shift of the grip element causing the loading unit to shift. The movement means has at least a pulley placed between the grip element and the loading unit and connected in a kinematic manner to the latter by means of at least a flexible element.

Abstract: A multipurpose exercise machine requiring only three points of adjustment centrally located. It has a one point height adjustment and two adjustments for the rotating arm assemblies. Dip and chin up bars are attached to the arm assemblies. The machine contains an integrated swingable workout bench. Through the use of a pulley system and counter balance assembly, the cable system maintains tension and provides a constant length of cable.

Abstract: Machines, apparatuses, systems and methods for providing adjustable tension to a cable system using a pivotally mounted leverage mechanism that employs an adjustably positionable weight. Embodiments are used in exercise and other muscle strengthening devices, and may include an electronic control system for monitoring, recording a user's progress, and for altering or releasing tension to the cable system based on feedback from the user. Embodiments include a user interface for inputting information for particular exercises or workouts, as well as outputting/downloading information following exercises or workouts. Other embodiments allow adjustment to the starting point of the lifting bar so that such machines may be used for bench presses, squats, cleans or curls.

Abstract: An exercise machine applicable for strengthening a user's abdominal muscles is described. The exercise machine can include a base frame to provide ground support, a mounting assembly rotably mounted over the base frame, a backrest assembly movably coupled to the mounting assembly via one or more pivot joints for swivel movements along the base frame and a handle assembly adjustably affixed to the backrest assembly to allow a user sitting on the seat pad to induce the swivel movements via the backrest assembly.

Abstract: This disclosure provides a weight support assembly including a main support mountable to an upright frame member to define a coarse position and a secondary support movable relative to the main support to define a fine position.

Abstract: Exercise apparatus having a slidable weight bar assembly with hand brake assemblies is provided for engaging and disengaging the weight bar assembly with a support frame. The exercise apparatus can be configured as a squat machine or a bench press. The exercise apparatus can include an adjustable back support that facilitates proper positioning and support of the operator's upper and lower back while performing squat exercises. The exercise apparatus can further include spring assemblies that increase the kinetic load during downward movements of the slidable weight bar assembly. Alternatively, the spring assemblies can be incorporated into exercise apparatus having a slidable weight bar assembly without the hand brake system.

Abstract: An exercising apparatus for exercising muscles in the abdominal region of a user's body may include a stationary primary body support configured to support upper portions of the user's body including the abdominal region. The primary body support may include a primary body support surface oriented to support a user's back in a rearwardly inclined position and a secondary body support surface for supporting the user's buttocks. A movable carriage may be configured to be engaged by the user's lower leg portions and may be movable along a substantially linear path extending generally toward and generally away from the secondary body support surface. A resistance application assembly may be configured to apply an adjustable degree of biasing force to the carriage in a direction generally away from the secondary body support surface to resist movement of the carriage toward the secondary body support surface.

Abstract: Exercise apparatus having a slidable weight bar assembly with hand brake assemblies is provided for enaging and disengaging the weight bar assembly with a support frame. The exercise apparatus can be configured as a squat machine or a bench press. The exercise apparatus can include an adjustable back support that facilitates proper positioning and support of the operator's upper and lower back while performing squat exercises. The exercise apparatus can further include spring assemblies that increase the kinetic load during downward movements of the slidable weight bar assembly.

Abstract: An exercise device with an arc shaped track having a concave side that is mounted upon a support structure that supports the arc shaped track at a position in which the concave side of the arc faces downward and in which the arc shaped track can be fixed at a location centered above a user's head to extend to each side of the user. When in use, a track follower engages the track and moves along a length of the track to follow a course defined by the arc shape of the track. A handle is coupled to the track follower to be gripped by the user's hand to guide the user's side to side bends. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

Abstract: An adjustable exercise bar comprises a bar (145) and one or more rails (100, 105) upon which one or more bar retainers are constrained to move. The rails are secured to a vertical surface such as a wall or post (110). A plunger assembly (400) contained within the bar retainers is coupled to the bar by a stiff metal band that is attached to the bar. A plunger in each plunger assembly is normally inserted in a hole (115) in the rail or rails, preventing the bar retainer from moving. The plunger assembly is actuated by rotating the front of the bar upward (from the user's perspective). This actuation causes the plunger (405) to be removed from the hole, enabling movement of the bar upward or downward. When the rotational force on the bar is removed, a spring (435) within the plunger assembly returns the bar to its original rotational position and returns the plunger to a hole in the rail. An optional weight (155) secured to the bar retainers by cords (160, 161) acts as a counterbalance to bar movement.

Abstract: An exercise apparatus for exercising multiple body parts includes a frame and a front user bearer assembly which is angularly and height adjustable relative to the frame. The front bearer assembly is mounted to a guide for guiding upward and downward movement of the front bearer assembly. A compensator to ensure that the front assembly travels in a substantially vertical plane during exercise includes a number of support elements, which are pivotally mounted.

Abstract: An abdomen exercising device includes a soft cushion, a base combined with the cushion, a sliding unit slidably mounted on the base, an elastic cord biased between the base and the sliding unit to provide a damping force to the sliding unit and a top cover mounted on the base to cover the elastic cord and to partially cover the sliding unit. Thus, the parts of the abdomen exercising device are almost hidden between and covered by the base and the top cover to prevent the user from being clamped or scratched by the elastic cord or the sliding unit during the exercising process so as to protect the user's safety.

Abstract: Apparatus for exercising muscles of the chest and back includes a frame, parallel bars and overhead bars attached to the frame. A seat supports a user during exercise and a weight stack can be adjusted to suit the user. The seat is vertically movable relative to the frame as exercises are being performed by the user.

Abstract: A device and method for bilateral upper extremity training for patients with a paretic upper extremity, the device facilitating cortical remodeling, sustained relearning, and improvement in functional outcomes in paretic and possibly non-paretic upper extremities. In one variation, the device includes a base, an adjustable chest plate for placing the user at a set distance from the device and isolating arm movement, an incline plate attached and inclinable relative to the base, two width plates adjustably attached to the incline plate, and two swivel plates adjustably attached to the width plates. In one variation, the swivel plates are swivalable relative to a fixed point in a plane parallel to the plane of the width plates. In another variation, the swivel plates are pivotably attached to the width plates. Other features of the device include a counter for counting user activity, and audible and visual cueing devices for facilitating sustained learning.

Abstract: A leg press exercise machine that provides translational and rotational motion of the user support structure by translating the user support structure along two intersecting non-orthogonal linear paths. A front portion of the user support structure travels along an inclining linear path and a rear portion of the user support structure travels along a declining linear path. The translation of the user support structure along the inclining and declining linear paths results in the user support structure exhibiting a rational motion, defining an arcuate path.

Abstract: A handicapped accessible exercise apparatus having a central housing with two pivoting extension arms. Cables extend from weight stacks within the housing to movable cable guides on the arms for engagement by a user. By adjusting the positions of the arms and the cable guides, the apparatus can be configured to facilitate various exercises and to accommodate users of various sizes. The apparatus is provided with button-operated locks for allowing users with limited manual dexterity to easily lock and unlock the positions of the extension arms and the cable guides.

Abstract: The present invention is an exercise machine which includes a moveable section connected to a frame such that the moveable section is independently and simultaneously moveable along an horizontal direction and vertical direction. The exercise machine further includes and a weight stack operably connected to the moveable section, such that the weight stack providing resistance to movement of the moveable section; and a frame operably supporting the moveable section and the weight stack.

Abstract: The present invention relates to an exercise apparatus which is a multiple functions exercise apparatus. One function of the exercise apparatus allows the user taking chin-up exercise substantially solely by his fingers. The exercise apparatus comprises a frame, two guiding mechanisms respectively connected to the left and right sides of the frame, a load unit positioned on the frame, a cable-and-pulley device connected to the frame and linked the load unit and the guiding mechanisms, and the cable-and-pulley device further having two pulling portions engaged with respective guiding mechanisms, at least an exercise accessory operable connected to at least one pulling portion, at least two climbing-holds mounted on the frame for the user gripping thereon and taking chin-up exercise.

Abstract: A multi-purpose exercise apparatus used for linear and rotational resistance exercises with varying heights, diameters, angular ranges and planes. The apparatus relates to a frame (frame 430) and at least one carriage (300) supported by and movable on the frame. The carriage (300) supports at least one spooling force transmitter (102), and/or at least one translating force transmitter (101), which is connected to a resistance source (resistance source 494) through a flexible connector (476). The spooling force transmitter (102) is connected to a rigid arm (390) to which the user can apply rotational force against the spool and connected resistance. The spooling force transmitter (102) pivots on a positioning axis that is coincident with the longitudinal axis of the flexible connector (476) immediately before the connector attaches to the spooling force transmitter (101). The user can apply force to the translating force transmitter (101) to perform guided straight-line motions in a variety of directions.

Abstract: Apparatuses having selective having selective resistance, related mechanisms and devices, and methods to operating exercise equipment are provided. In one embodiment, the exercise apparatus includes a frame and at least one guide member coupled with a portion of the frame. A weight stack, including a plurality of weight plates, is associated with the at least one guide member. The exercise apparatus also includes a resistance selector having at least one rail coupled to an uppermost weight plate of the plurality of weight plates. A body is slidably coupled to the at least one rail. A pin is slidably coupled to the body and configured to be displaced between at least a first position and a second position relative to the body. An engagement structure is coupled with the pin and configured to selectively engage at least one abutment shoulder of at least one weight plate of the plurality of weight plates.

Abstract: An inferior limb muscle force training apparatus is provided with a supporting strut standing vertically, a seat body provided so as to be capable of ascending/descending along the supporting strut, and a weight balancing mechanism which applies a lift force to the seat body, wherein the seat body is provided with a saddle type seat portion and a pair of shoulder pads, and the weight balancing mechanism is constituted to be capable of adjusting a lift force applied to the seat body properly by winding ropes on pulleys provided on an upper portion of the supporting strut, linking one ends of the ropes to the seat body, and linking the other ends thereof to a weight placing stand provided on a back side of the supporting strut so as to be capable of ascending and descending.

Abstract: A weight system includes a selector configured to selectively couple incremental weights that extend through a weight stack to a weight lift.

Abstract: A weight bar slide assembly, for use with weightlifting equipment having vertical guide bars that provide for an accurate simulation of the free weight lifting motion. The weight bar slide assembly has a weight bar sleeve to rotatably receive a weight bar. A rod is attached to the weight bar sleeve and extends outwardly therefrom. A rod sleeve rotatably receives the rod. The rod may rotate along its longitudinal axis inside the rod sleeve. The rod sleeve is attached to a vertical guide. The vertical guide is movably mounted to a vertical guide bar. The longitudinal axis rotation of the rod within the rod sleeve allows for the freedom of motion found in the free weight lifting motion. The weight bar slide assemblies attached to opposing ends of the weight bar may move linearly along the vertical guide bar independently of each other.

Abstract: An exercise apparatus for exercising multiple body parts comprises a frame 1 and a front user bearer assembly 2 which is angularly and height adjustable relative to the frame 1. The front bearer assembly 2 is mounted to a guide means for guiding upward and downward movement of the front bearer assembly 2. Compensating means to ensure that the front assembly travels in a substantially vertical plane during exercise comprises a number of support elements 50, 51 which are pivotally mounted.

Abstract: A safety locking system is used on an exercise device. The locking system includes a first pawl that is mounted to a pawl shaft. The pawl shaft is movably mounted to a lock frame, which can also support a weight collar, adapted to receive weight plates to provide additional resistance to exercise. A second pawl is movably mounted to the lock frame and is connected to the first pawl by way of a spring or other bias mechanism. The lock frame limits the movement of the second pawl so as to provide a bias of the first pawl toward engagement of the pawl to a rack provided with the exercise device. The engagement of either pawl with the rack restricts movement of the lock frame in at least one direction, with gravity. If the bias spring breaks or becomes disengaged from either the first pawl or the second pawl, the second pawl is counterweighted to engage with the rack.

Abstract: Exercise apparatus has a biased tolerance-compensating engagement system between a seat-supporting carriage and a tubular support column to provide zero clearance between adjustment rollers and the support column, to minimize wobble during user adjustment.