Background art Today's urban men the most time of their life spend sitting or lying, so, the most used things at the work and at home are the chair and the bed, consequently, the biggest attention should be payed to their functional and ergonomic characteristics.

Sitting is not so natural body position. but, bad, irregular sitting and poor pos what is mostly the case) is the cause of many health problems (backpain, spine distortion. weakcning of spine muscles, lumbago, troubles in the lower part of the gastrointestinal tract, poor blood circulation, etc,..).

We are all different shapes and sizes and we all need different chairs adapted to us.

But, the chairs on the markets are equalized, that is, there are not possibilities to adapt those chairs to individual physical and anatomic characteristics to user.

On the other handnmssage arm-chairs work with electromotors what is complicated and expensive.

I consider that the further described invention with its innovatory solutions can better suit individual demands to user that need or want the ergonomic adaptable chair for dynamic sitting, what is orthopeds and industrial physician recommendation.

Enclosure of the invention The purpose of this invention is to solve above mentioned problems of sitting.

The next purpose is application of the same innovative solutions to arm-chairs,sofas and beds.

Elastic, flexible slats are applied by the chair (l) : wooden but can also be made of metal, plastic or composed materials. They are placed transversaly and o egading the sitting person) both on the seat and on the back of the chair.

Only by the chairs for male population (from anatomic and physiology reasons-in order to make possible free position and vertical movement of genitals) on the front part of the seats are applied wavy shape slats (2) : convex at the ends and concave in the middle.

The ends of each slats are placed in the open side of the metal casing (3) and are supported by spring in the rniddle (4) serving as additional shock absorber by slats vertical movements during sitting loading. On the other side the metal casing is closed, but has the hole with thread for the screw (5) with knob (6) for the slats tension adjustment. Only that adjustment knob (6) is visible outside lateral frames (10) of the seat and the back-of the chair.

Those metal casing (3) with mechanism for hand adjustment of the each slats tension are fastened with the hinges (7, 8) and screw (9) for lateral hollow metal frames(10) of the seat and back. Mechanism for the slats tension, in simply version, can be worked out without spring (4) in the casing. Lateral metal frames(10),left and right, of the seat and the back are tied up with transversaly placed elements (11, 12).

Above described can be applied by arm-chairs,sofas and beds as well.

The slats bending tension adjustment that is hardness and ac esistance dthe ench separate slat permit ergonomic adjustment to every user in accordance to his dimensions and weight and dynamic sitting for profilactic or therpeutic purposes.Flexible slats with their convex shape and natural elastic properties of the applied materials,perform activ props to parts of the body, that is, give controlled activ resistance to the weight of the leaned body parts , massage them, increasing muscle tonus and blood circulation and so concentration and work enBct. The back is high and support the spins up to cervical vertebrae, and through active props of the slats take some weight of the body and partly disburden the load to the lumbar verttebrae and the pelvis.

The slope of the back can be changed through the mechanism as applied by iront seats of the car, with knob (13) rotation.

The chair is on the down part fixed with legs on the wheels and central placed hydraulic absorber for the height adjustment of the seat, as it is usual bs oEce chairs.

Additionaly, the chair has the mechanism for inclination of the seat toward j&ont or to back : On the top of the hydraulic absorber additional frame (18) is fixed, connected to the back of the seat with hinges (17). On the front side this frame (18) is connected with the seat through toothed wheels (15) assembled on the same axle as the knob (14) for the seat's inclination adjustment, and toothed gear segment (16) which upper end is fixed with the seat. Turning of the knob (14) are turned on the same axle assembled tooth wheels (t5), moving the gear segment (16) up or down,causing changing of the seat's inclination towards front or to back.

The chairs, arm-chairs, sofas and beds worked out in accordance to proposed concept are possible in various modifications and variants Jbut all in the scope of above described innovations. Besides, all particular details of the innvention could be exchanged by technical equivalents.

FIG. 1 presents perspectiv view of the common type chair ; FIG. 2 presents the same chair, but in male population variant ; FIG. 3 presents cross section through the chair, FIG. 4 presents lower additional frame with tle mechanism for the inclinaion adjustment of the seat; FIG. 5 presents detail of cross section through the mechanism for slat bending tension.