the present invention relates to a resistance training device , generally referred to by reference number 10 , which is configured to maximize pectoral exercises while being convenient for home , office or abroad . as shown in fig1 , 2 and 4 , the resistance training device 10 includes a pair of adjustment mounting rails or rods 11 attached in parallel to a header and a side of a door frame by mounting or anchoring blocks or assemblies 20 . an exercise platform 40 slidably mounts to the adjustment rods 11 and may be fixed in the desired position by a pair of clamps 33 . the adjustment rods 11 are angled rods providing the two areas of adjustable mounting of the anchoring blocks 20 , one to the side of the door frame and the other to the header . additional anchoring blocks 20 may be used adjacent either the header , side of the frame or both for increased stability . although only one pair of clamps 33 are shown in the figures , attached to the rods 11 below the platform 40 , additional pairs may be mounted atop the exercise platform 40 . alternatively , the exercise platform 40 may include clamping assemblies to fix the position thereof along the adjustment rods 11 . as more clearly shown in fig3 , each anchoring block 20 includes a base 24 and a pair of movable jaws 21 , 22 defining a c - clamp . the anchoring block 20 may be covered with a layer of compressible material , both for aesthetics and protection . the base 24 includes a pair of bores 28 for the adjustment rods 11 to permit the anchoring block 20 to slide thereon . to fix the anchoring position of the anchoring block 20 on the rods 11 , the base 24 includes at least one curved pressure pad inside each bore 28 . the pressure pad 28 conforms to the shape of the adjustment rod 11 and may be clamped thereto by a wing screw 27 or thumb screw . the pressure pad 28 may be covered with friction enhancing material or layer to increase clamping performance . each movable jaw 21 , 22 is hinged to the base 24 and moves or pivots in the direction indicated by arrow 12 in fig3 . a tension spring 29 between the jaws 21 , 22 maintains or biases the jaws 21 , 22 in the closed position , as shown in fig3 . opening of the jaws 21 , 22 allows them to be wrapped behind door frame members or jambs of various dimensions . to ensure that the jaws 21 , 22 are properly hooked onto the door frame member , the distal end of each jaw 21 , 22 includes an appendage or finger having a movable or pivotable finger pad 23 . each pad 23 is movable or pivotal so that it may easily hook behind the door frame member or molding . each pad 23 may also include a layer or covering to protect the molding and / or to increase grip thereon . to clamp the anchoring block 20 onto the door frame member , the anchoring block 20 includes a compressible brace 31 attached to an end of a wing screw 30 or thumb screw . the brace 31 may be made from relatively elastic material that permits strong clamping engagement with the door jamb without marring the surface thereof . thus , when the anchoring block 20 has been properly adjusted and mounted , the door jamb is disposed between the pads 23 and the brace 31 and the anchoring block 20 is clamped to the door jamb by turning the wing screw 30 . it is noted that the brace 31 may be notched to conform to the interior shape of the door molding . referring to fig2 , 4 and 6 , the exercise platform 40 may be a substantially rectangular block defining a carriage 41 . as with the anchoring blocks 20 , the carriage 41 may include a covering of compressible material for aesthetics and protection . the carriage 41 includes a pair of bores 43 permitting the carriage 41 to adjustably slide along the adjustment rods 11 . the carriage 41 also includes another pair of bores 42 for insertably mounting the pectoral , butterfly handles 46 . intermediate the top and bottom ends of the carriage 41 , a pair of oppositely disposed cavities 44 are formed congruent with the bores 42 . the cavities 44 receive resistance blocks 50 which provide the desired resistance for the resistance training device . a spacer brace 45 may be disposed or formed at the rear of the carriage 41 to brace the exercise platform against the door jamb . the brace 45 may be a separate element that is biased against the door jamb in a passive or selective manner , e . g . compression springs , and / or the brace may be formed with similar materials to the brace 31 for similar effect . each butterfly handle 46 may be a substantially j - shaped member having a handle bar 48 defining the shape . a padded grip 47 is disposed at one end , and the other end of the handle bar 48 includes a split end 49 . the padded grip 47 permits the user to place their forearm thereon while performing the exercise as well as providing areas for the user to grip . the resistance training device 10 includes interchangeable resistance blocks or plugs 50 for selectively defining the resistance of the device 10 . the user may be provided with a plurality of resistance block sets , each set having a resistance different from the other . as shown in fig5 , each resistance block 50 may be a substantially solid cube having a cylindrical core 51 , the cubes being mounted in cavities in the platform 40 so that the cubes do not rotate . the cylindrical core 51 is split to form semi - cylindrical hollow through holes or bores 53 . these bores 53 are adapted to receive the slotted split end 49 of a respective butterfly handle 46 to form a male / female connection thereby . when the split end 49 is connected to the core 51 , rotation of the handle 46 concurrently rotates the core 51 . in the preferred embodiment , the cylindrical core 51 is integral inside the resistance block via integral springs 52 . the springs 52 bias the core 51 in one direction such that turning the handle 46 in the opposite direction requires the user to act against the bias or resistance of the springs 52 . as an alternative , the leaf - like coil spring 52 may be replaced with a torsion spring surrounding the core 51 and securely attached to the interior of the resistance block 50 . as a further alternative , the resistance block may be made from durable rubber with the two semi - cylindrical through holes or bores 53 formed thereon . the central partition between the bores 53 would be substantially increased in durability such that during operation , the central partition may deform without breaking . it is noted that in all instances , any durable material with limited deformation characteristics may be used to make the resistance block 50 with the desired resistance . to ensure long lasting operation of the resistance training device 10 , the distal end of the split end 49 may be covered by a reinforced cap 13 to minimize or prevent deformation of the split end 49 . the following describes how to use the resistance training device 10 . to ready the training device 10 , the user mounts one of the anchoring blocks 20 to a door jamb as noted above . the pair of adjustment rods 11 are threaded through bores 28 in the mounted anchor block 20 and clamped via pressure pads 26 . the exercise platform 40 is slidably mounted to the adjustment rods 11 and clamped at the desired height by clamps 33 . the other end and the header area of the adjustment rods 11 are then secured to the door jamb by additional anchoring blocks 20 . pre - selected resistance blocks 50 are installed in the cavities 44 formed in the exercise platform 40 . then the butterfly handles 46 are insertably mounted through the bores 42 , 53 and the resistance training device is ready for use . as noted above , exercise is a great health benefit for everyone . the pectoral muscles are one of the major muscle groups that with regular exercise , will help burn more calories and reduce weight . as such , the resistance training device 10 provides an effective workout for the pectorals , and due , in part , to relatively few parts and low complexity , the resistance training device 10 may be easily assembled / disassembled for storage and transport . it is noted that the resistance training device 10 may encompass a variety of alternatives . for example , the coverings mentioned above may be comprised of vinyl , rubber , composites or other similar materials . the rods 11 and the handle bars 48 may be made from durable yet relatively lightweight metals to increase portability . the resistance training device 10 may be colored and / or include indicia . it is to be understood that the present invention is not limited to the embodiments described above , but encompasses any and all embodiments within the scope of the following claims .
the resistance training device includes a pair of adjustment rails attached to a door frame by at least two mounting blocks . an adjustable exercise platform includes a slidable carriage riding on the adjustment rails to adjustably set the height of the exercise platform . the exercise platform includes a pair of oppositely disposed cavities for receiving resistance blocks . the resistance block provides a predetermined amount of exercise resistance and is interchangeable with other resistance blocks to vary the resistance . a pair of pectoral , butterfly handles are insertably mounted bores in the support block and the resistance block to allow the user to perform butterfly exercises . the resistance training device is easy to assemble / disassemble for storage or transport .