Chair type stretching apparatus

A chair type stretching apparatus having a seat and a backrest which respectively have individual widths along a width of a user's body, and a depth, said stretching apparatus comprising:

• a flexible sheet being disposed on a top of said seat to extend an entire width of said seat for supporting the user's buttocks, said flexible sheet being configured to be movable between a normal position and a projected position, said flexible sheet in said normal position lying in a close relation with a top surface of said seat, said flexible sheet in said projected position is spaced away from said top surface of said seat,
• a tension means being provided on said seat and being configured to apply tensional force to said flexible sheet so as to move a center of said flexible sheet toward an upper direction of the seat,
• a controller being configured to control said tension means in order to move said center of said flexible sheet to a vertical direction,
• wherein
• said tension means is provided on at least one width end of said seat in order to apply the tensional force along a width direction of the seat to said flexible sheet, whereby the tension means moves the center of the flexible sheet to the vertical direction.