the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention . as used herein , the term “ and / or ” includes any and all combinations of one or more of the associated listed items . as used herein , the singular forms “ a ,” “ an ,” and “ the ” are intended to include the plural forms as well as the singular forms , unless the context clearly indicates otherwise . it will be further understood that the terms “ comprises ” and / or “ comprising ,” when used in this specification , specify the presence of stated features , steps , operations , elements , and / or components , but do not preclude the presence or addition of one or more other features , steps , operations , elements , components , and / or groups thereof . unless otherwise defined , all terms ( including technical and scientific terms ) used herein have the same meaning as commonly understood by one having ordinary skill in the art to which this invention belongs . it will be further understood that terms , such as those defined in commonly used dictionaries , should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein . in describing the invention , it will be understood that a number of techniques and steps are disclosed . each of these has individual benefit and each can also be used in conjunction with one or more , or in some cases all , of the other disclosed techniques . accordingly , for the sake of clarity , this description will refrain from repeating every possible combination of the individual steps in an unnecessary fashion . nevertheless , the specification and claims should be read with the understanding that such combinations are entirely within the scope of the invention and the claims . new sliding exercise apparatuses are discussed herein . in the following description , for purposes of explanation , numerous specific details are set forth in order to provide a thorough understanding of the present invention . it will be evident , however , to one skilled in the art that the present invention may be practiced without these specific details . the present disclosure is to be considered as an exemplification of the invention , and is not intended to limit the invention to the specific embodiments illustrated by the figures or description below . the present invention will now be described by example and through referencing the appended figures representing preferred and alternative embodiments . fig1 illustrates an example of a sliding exercise apparatus (“ the apparatus ”) 100 in use by a user 200 according to various embodiments . in this example , the apparatus 100 comprises a hard layer frame 11 and a soft layer 12 , and the user 200 has placed their foot onto the soft layer 12 of the apparatus 100 , while the hard layer frame 11 may contact a surface such as a floor . by moving their foot while it is resting on the soft layer 12 of the apparatus 100 , the hard layer frame 11 may allow the user 200 to perform movements such as flexion and extension movements by decreasing the frictional resistance between the apparatus 100 and softer floor coverings such as carpets , rugs , and the like . alternatively , the user may turn the apparatus 100 over and place their foot onto the hard layer frame 11 of the apparatus 100 , while the soft layer 12 may contact a surface such as a floor . by moving their foot while it is resting on the hard layer frame 11 of the apparatus 100 , the softlayer 12 may allow the user 200 to perform movements such as flexion and extension movements by decreasing the frictional resistance between the apparatus 100 and harder floor coverings such as tiling , hard wood , linoleum , and the like . in further embodiments , a user 200 may place another appendage such as a knee , calf , thigh , hand , elbow , forearm , upper arm , hip , shoulder , head onto either the soft layer 12 or the hard layer frame 11 , while the opposite hard layer frame 11 or soft layer 12 , respectively , may allow the user 200 to perform movements such as flexion movement , extension movements , or any other movements by decreasing the frictional resistance between the apparatus 100 and softer or harder floor coverings . fig2 illustrates a perspective view of a first side of an example of a sliding exercise apparatus 100 comprising a soft layer 12 according to various embodiments described herein . in preferred embodiments , a soft layer 12 is configured to slide over a surface or floor covering such as tiling , hard wood , linoleum , and other like hard floor coverings with generally low frictional resistance . the soft layer 12 may be positioned on a first or second side of the apparatus 100 , preferably positioned on an opposite side of the apparatus 100 relative to the hard layer frame 11 , and may comprise a substantially flexible and preferably fabric or cloth material such as natural and synthetic felt materials , synthetic fabrics such as polyester , astroturf - like materials , acrylic , nylon , rayon , acetate , spandex , lastex , and kevlar , and natural fabrics such as coir , cotton , hemp , jute , leather , linen , ramie , wool , silk , or any other suitable flexible natural or synthetic material including combinations of materials . a soft layer 12 may comprise one or more soft surfaces 15 which are configured to reduce frictional resistance between the soft layer 12 and a solid floor covering such as a wood or linoleum floor . in preferred embodiments , a soft surface 15 may comprise a generally planar shape and / or a substantially smooth or uniformly textured finish . a generally planar shape and / or a substantially smooth or uniformly textured finish may allow a soft surface 15 to slide over a hard floor covering such as hardwood flooring with little frictional resistance between the soft surface 15 and the floor covering . in further embodiments , a soft layer 12 of an apparatus 100 may comprise two , three , four , or more soft surfaces 15 , each of which may be configured to contact a floor covering and to reduce frictional resistance between the softlayer 12 and the floor covering . it should be noted that the apparatus 100 may be used by a person in variety of positions such as in the sitting position ( e . g . sitting on a chair or bench ), long sitting ( e . g . sitting upright on mat or bed with legs extended ) or alternatively in a supine position ( e . g . laying on the ground , table , or bed ). turning now to fig3 , a perspective view of a second side of an example of a sliding exercise apparatus 100 comprising a hard layer frame 11 according to various embodiments described herein is shown . in preferred embodiments , a hard layer frame 11 is configured to slide over a surface or floor covering such as carpeting , rugs , and other like soft floor coverings with generally low frictional resistance . the hard layer frame 11 may be positioned on a first or second side of the apparatus 100 , preferably positioned on an opposite side of the apparatus 100 relative to the soft layer 12 , and may comprise a substantially rigid material such as nylon , polytetrafluoroethylene ( ptfe ), polyethylene terephthalate ( pet ), high - density polyethylene ( hdpe ), polyvinyl chloride ( pvc ), polypropylene ( pp ), low density polyethylene ( ldpe ), other substantially rigid plastics , resins , ceramics , wood , carbon fiber , glass , metals and metal alloys , or any other suitable flexible natural or synthetic material including combinations of materials . a hard layer frame 11 may comprise one or more hard surfaces 14 which are configured to reduce frictional resistance between the hard layer frame 11 and a floor covering . in preferred embodiments , a hard surface 14 may comprise a generally planar shape and / or a substantially smooth finish . a generally planar shape and / or a substantially smooth finish may allow a hard surface 14 to slide over a soft floor covering such as carpeting with little frictional resistance between the hard surface 14 and the floor covering . in further embodiments , a hard layer frame 11 of an apparatus 100 may comprise two , three , four , or more hard surfaces , each of which may be configured to contact a floor covering and to reduce frictional resistance between the hard layer frame 11 and the floor covering . as perhaps best depicted in fig2 and 3 , in some embodiments , the apparatus 100 may be configured with a generally peanut shape wherein the hard layer frame 11 may comprise and terminate with a first rounded end 17 on one end , a terminate at a second rounded end 17 on an opposing end , and two concave central regions connecting the first rounded end 17 to the second rounded end 17 . in some further preferred embodiments , the soft layer 12 and / or the cushion layer 13 of the apparatus may also be configured with a peanut shape that is generally complementary in shape to a hard layer 11 configured in a peanut shape . a peanut shape may be configured to accept the foot and other appendages as generally comprising a first rounded end 17 , a second rounded end 17 , and two concave central regions connecting the first rounded end 17 to the second rounded end 17 that are generally larger in size than a user &# 39 ; s foot or other appendages . it should be understood to one of ordinary skill in the art that the hard layer 11 , the soft layer 12 , and / or a cushion layer 13 may be configured in a plurality of sizes and shapes including “ t ” shaped , “ x ” shaped , square shaped , rectangular shaped , cylinder shaped , round shaped , cuboid shaped , hexagonally shaped , triangular shaped , or any other geometric or non - geometric shape , including combinations of shapes . it is not intended herein to mention all the possible alternatives , equivalent forms or ramifications of the invention . it is understood that the terms and proposed shapes used herein are merely descriptive , rather than limiting , and that various changes may be made without departing from the spirit or scope of the invention . as perhaps best shown in fig2 - 6 , in preferred embodiments , a hard layer frame 11 may comprise a beveled edge 11 a that extends around and from the perimeter of a hard surface 14 that curves away from a hard surface 14 towards a soft surface 15 of the soft layer 12 . in other embodiments , a hard layer frame 11 may comprise two or more beveled edges 11 a that extends around and from portions of the perimeter of a hard surface 14 , and that curve away from a hard surface 14 towards a soft surface 15 of the soft layer 12 as shown in the cross - sectional views of examples of the apparatus 100 illustrated in fig4 - 6 . also in preferred embodiments , a beveled edge 11 a is configured to not extend above a soft surface 15 so that when a soft surface 15 placed on a surface such as a floor covering , a beveled edge is unable to contact the floor covering . in further embodiments , a beveled edge 11 a is configured to soften the edge of a hard layer frame 11 for the sake of safety , wear resistance , reducing frictional resistance as a hard surface 14 slides over a surface such as a floor covering , aesthetics , or to facilitate coupling the hard layer frame 11 with another element such as a soft layer 12 or cushion layer 13 . in some embodiments , a beveled edge 11 a may comprise a generally planar edge or bevel that extends away from a hard surface 14 at an angle . in other embodiments , a beveled edge 11 a may comprise a generally planar edge or chamfer that extends away from a hard surface 14 at an angle . in further embodiments , a beveled edge 11 a may comprise a generally rounded or concave edge that extends away from a hard surface 14 in a curved manner . in preferred embodiments and in those depicted in fig4 - 6 , an apparatus 100 may comprise one or more cushion layers 13 comprising a resilient material which may be positioned between a hard layer frame 11 and a soft layer 12 . a cushion layer 13 may be configured to absorb impacts or provide a resilient cushioning layer between a hard layer frame 11 and a soft layer 12 . in preferred embodiments , a cushion layer 13 may comprise silicone rubber . in other embodiments , a cushion layer may comprise artilage foams , poron foams , silicone foams , rubber foams , plastic foams , neoprene foam , latex foam rubber , polyurenthane foam rubber , or elastomer materials such as elastic plastics , elastic silicone , elastic rubbers , silicone rubbers , or any other suitable elastomer or resilient material including combinations of materials . in preferred embodiments , the hard layer frame 11 is coupled to a first side of a cushion layer 13 , while the soft layer 12 is coupled to a second side of the cushion layer 13 . in other embodiments , the hard layer frame 11 is coupled to a first cushion layer 13 , the soft layer 12 is coupled to a second cushion layer 13 , and the two cushion layers 13 are coupled together . in further embodiments , the hard layer frame 11 may be coupled to a first cushion layer 13 , the soft layer 12 is coupled to a second cushion layer 13 , and one or more other cushion layers 13 are coupled between the two cushion layers 13 that are coupled to the hard layer frame 11 and the soft layer 12 . in alternative embodiments , a hard layer frame 11 may be coupled to a soft layer 12 the hard layer frame 11 , soft layer 12 , and optionally one or more cushion layers 13 may be coupled be being connected , removably connected , or integrally formed or molded together . in some embodiments , the hard layer frame 11 , soft layer 12 , and optionally one or more cushion layers 13 may be permanently coupled or connected together with heat bonding , chemical bonding , adhesives , clasp type fasteners , clip type fasteners , rivet type fasteners , threaded type fasteners , other types of fasteners , or any other suitable joining method . in other embodiments , the hard layer frame 11 , soft layer 12 , and optionally one or more cushion layers 13 may be temporarily coupled or removably connected by being press fit or snap fit together , by one or more fasteners such as magnetic type fasteners , sealable tongue and groove fasteners , clip type fasteners , clasp type fasteners , ratchet type fasteners , a push - to - lock type connection method , a turn - to - lock type connection method , slide - to - lock type connection method or any other suitable temporary connection method as one reasonably skilled in the art could envision to serve the same function . in further embodiments , the hard layer frame 11 , soft layer 12 , and optionally one or more cushion layers 13 , and / or any other element described herein may be coupled by being one of connected to and integrally formed with another element of an apparatus 100 . in some embodiments , an apparatus 100 may comprise a non - slip layer 16 ( fig5 and 6 ). in preferred embodiments , a non - slip layer 16 may be temporarily coupled to a soft surface 15 ( fig5 ) so that a user may place an appendage such as a foot on the non - slip layer 16 to prevent their appendage from slipping off of the apparatus 100 as the user manipulates the apparatus 100 by sliding a hard surface 14 over a surface such as a soft floor covering . in other preferred embodiments , a non - slip layer 16 may be temporarily coupled to a hard surface 14 ( fig6 ) so that a user may place an appendage such as a foot on the non - slip layer 16 to prevent their appendage from slipping off of the apparatus 100 as the user manipulates the apparatus 100 by sliding a soft surface 15 over a surface such as a hard floor covering . in preferred embodiments , a non - slip layer 16 may comprise or be constructed from dycem ®. in other embodiments , a non - slip layer 16 may comprise vinyl , artilage foams , poron foams , silicone foams , rubber foams , plastic foams , neoprene foam , latex foam rubber , polyurenthane foam rubber , or elastomer materials such as elastic plastics , elastic silicone , elastic rubbers , silicone rubbers , rubberized fabrics and webbings , grip fabrics , grip tapes , textured fabrics , or any other suitable friction enhancing material . a non - slip layer 16 may preferably be temporarily coupled to a hard surface 14 or soft surface 15 by simply placing the non - slip layer 16 onto the hard surface 14 or soft surface 15 and then placing an appendage such as a foot onto the non - slip layer 16 . in other embodiments , a non - slip layer 16 may preferably be permanently or temporarily coupled to a hard surface 14 or soft surface 15 by any other suitable coupling method . fig7 illustrates an example of a sliding exercise apparatus 100 in use by a user 200 according to various alternative embodiments . in this example , the apparatus 100 comprises a hard layer frame 11 and a soft layer 12 , and the user 200 has placed their foot onto the soft layer 12 of the apparatus 100 , while the hard layer frame 11 may contact a surface such as a floor . by moving their foot while it is resting on the soft layer 12 of the apparatus 100 , the hard layer frame 11 may allow the user 200 to perform movements such as flexion and extension movements by decreasing the frictional resistance between the apparatus 100 and softer floor coverings such as carpets , rugs , and the like . in this particular embodiment , the apparatus 100 comprises parallel straight side edges with each side edge terminating in a rounded end 17 . although the present invention has been illustrated and described herein with reference to preferred embodiments and specific examples thereof , it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and / or achieve like results . all such equivalent embodiments and examples are within the spirit and scope of the present invention , are contemplated thereby , and are intended to be covered by the following claims .
in preferred embodiments , a sliding exercise apparatus comprises : a hard layer frame comprising a hard surface ; and a soft layer comprising a soft surface located opposite to the hard surface and located within the body of the hard layer frame . the apparatus may be inverted from a first orientation in which the hard surface is configured to make contact with the ground to a second orientation in which the soft surface is configured to make contact with the ground . the soft surface may comprise a fabric material , and the hard surface may comprise substantially rigid material with a planar ground contacting region and with a smooth finish . the hard layer may comprise a beveled edge that curves away from the hard surface towards the soft surface with the beveled edge extending to slightly below the soft surface .