Inclusion Criteria:  ● The participant is willing and able to give informed consent for participation in the study.  Male or Female, aged 18 years or above. For back pain group: diagnosed with AxSpa or long-standing non-specific LBP For healthy group: healthy with no long-standing back pain For the home setting, the participant must be capable of uploading videos from a smartphone or webcam.  Exclusion Criteria:  ● Has had surgery within 6 months of registration  Unable to stand independently Unable to pass screening questions to participate in physical activity Serious neurological condition preventing normal movement or walking ability Any severe medical conditions, such as cardiovascular disease