Apparatus for generating feedback on a test subject's body posture, the apparatus comprising: - a memory arranged for storage and retrieval of motion data and a plurality of parameters used in processing and evaluation of the motion data; - a clock arranged for providing an indication of time; - a motion recording device arranged for recording the motion data into the memory, the motion data including an angle between a direction (Ve) substantially along a length of a test subject's body extremity (201a, 201b) and a reference direction (Vt) as a function of the time provided by the clock; - a processor arranged for retrieving the motion data and parameters from the memory; and - a feedback device arranged for generating one or more of a visual, audio, or haptic feedback signal (Sf) and controlled by the processor, characterized in that said processor is programmed to execute the steps of ∘ retrieving the data and parameters from the memory; ∘ assigning the motion data into a first or second subset (C1, C2), the first subset defined as motion data wherein the angle remains within a threshold angle bandwidth for a period longer than a first threshold time period; the second subset defined as motion data not belonging to the first subset; ∘ calculating, for data assigned to the first subset in a first time window, a fraction of time wherein the angle exceeds a first threshold angle and/or calculating, for data assigned to the second subset in a second time window, a number of occurrences wherein the angle crosses a second threshold angle; and ∘ controlling the feedback device to generate the feedback signal (Sf) if either the fraction of time exceeds a threshold time fraction (Fm) or the number of occurrences exceeds an occurrence threshold (Nm). - a memory arranged for storage and retrieval of motion data and a plurality of parameters used in processing and evaluation of the motion data; - a clock arranged for providing an indication of time; - a motion recording device arranged for recording the motion data into the memory, the motion data including an angle between a direction (Ve) substantially along a length of a test subject's body extremity (201a, 201b) and a reference direction (Vt) as a function of the time provided by the clock; - a processor arranged for retrieving the motion data and parameters from the memory; and - a feedback device arranged for generating one or more of a visual, audio, or haptic feedback signal (Sf) and controlled by the processor, characterized in that said processor is programmed to execute the steps of ∘ retrieving the data and parameters from the memory; ∘ assigning the motion data into a first or second subset (C1, C2), the first subset defined as motion data wherein the angle remains within a threshold angle bandwidth for a period longer than a first threshold time period; the second subset defined as motion data not belonging to the first subset; ∘ calculating, for data assigned to the first subset in a first time window, a fraction of time wherein the angle exceeds a first threshold angle and/or calculating, for data assigned to the second subset in a second time window, a number of occurrences wherein the angle crosses a second threshold angle; and ∘ controlling the feedback device to generate the feedback signal (Sf) if either the fraction of time exceeds a threshold time fraction (Fm) or the number of occurrences exceeds an occurrence threshold (Nm). ∘ retrieving the data and parameters from the memory; ∘ assigning the motion data into a first or second subset (C1, C2), the first subset defined as motion data wherein the angle remains within a threshold angle bandwidth for a period longer than a first threshold time period; the second subset defined as motion data not belonging to the first subset; ∘ calculating, for data assigned to the first subset in a first time window, a fraction of time wherein the angle exceeds a first threshold angle and/or calculating, for data assigned to the second subset in a second time window, a number of occurrences wherein the angle crosses a second threshold angle; and ∘ controlling the feedback device to generate the feedback signal (Sf) if either the fraction of time exceeds a threshold time fraction (Fm) or the number of occurrences exceeds an occurrence threshold (Nm).