Participants in this group will continue with their current routine care and will be given a diary of exercises that they can do, which are usually given to them as part of their health care routine by physiotherapists or consultants. The diary has information about yoga-like stretching practices.

PBMCs will be isolated using centrifuge and then cultured with PMA ionomycin to stimulate cytokine release. Concentrations of released inflammatory cytokines will be compared to a control culture (no PMA ionomycin stimulation).

Using the validated Bath Ankylosing Spondylitis Functional Index (BASFI). The index assesses the functional limitation in patients with ankylosing spondylitis by asking the patient about symptom burden. The index consists of 10 questions evaluating how hard the patient finds situations i.e 'how difficult is it to put on your socks?' A score of 0 represents easy, and a score of 10 represents impossible. The mean (average) of the 10 questions is used to assign a symptom burden score of 0-10. The higher the score, the higher the symptom burden caused by ankylosing spondylitis.

Using the validated work productivity and activity impairment questionnaire (WPAI:GH). The questionnaire asks about the effect of health problems on the ability to work and perform regular activities. The questionnaire outcome is expressed as an impairment percentage, with higher numbers indicating greater impairment and less productivity.

Measured from the international physical activity questionnaire (IPAQ). The IPAQ asks 27 questions on physical activity (PA).

Those who score 'high' engage in: 1) vigorous activity on at least 3 days achieving a total PA of at least 1500 metabolic equivalent of task (MET) minutes a week - OR - 2) 7 or more days of any combination of walking, moderate intensity or vigorous intensity activities achieving a minimum total PA of at least 3000 MET minutes per week.

Those who score 'moderate' engage in: 1) 3 or more days of vigorous intensity activity and/or walking of at least 30 minutes per day - OR - 2) 5 or more days of moderate intensity activity and/or walking of at least 30 minutes per day

- OR - 3) 5 or more days of any combination of walking, moderate intensity, or vigorous intensity activities achieving a minimum total PA of at least 600 MET minutes per week.

Those who score 'low' do not fit the criteria of either the moderate or high levels of PA.

Using the validated Compliance Questionnaire Rheumatology (CQR). The CQR measures adherence to prescribed exercise or medication regimens in patients with rheumatic diseases, including ankylosing spondylitis. It consists of 19 items scored on a Likert scale, where 1 indicates "strongly disagree" and 4 indicates "strongly agree." The responses are combined to calculate a compliance score ranging from 0-100, with higher scores indicating better adherence to the intervention.

Using the validated Ankylosing Spondylitis Quality of Life (ASQoL) questionnaire. The ASQoL is a disease-specific instrument designed to measure the impact of ankylosing spondylitis on a patient's quality of life. It consists of 18 yes/no questions, with each "yes" response contributing to a total score. Scores range from 0 to 18, with higher scores indicating a greater impact of the disease on the patient's quality of life.

Using the EuroQol 5-Dimension (EQ-5D) questionnaire. The EQ-5D is a standardized instrument used to measure health-related quality of life across five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension is scored on a scale of 1 to 5, representing different levels of severity, with a total score reflecting the overall health status. Additionally, a visual analogue scale (VAS) is used to rate the patient's perceived health on a scale from 0 to 100, with higher scores indicating better health-related quality of life.

Using the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36). The SF-36 assesses overall health status across eight domains: physical functioning, role limitations due to physical health, bodily pain, general health perceptions, vitality (energy/fatigue), social functioning, role limitations due to emotional problems, and mental health. Each domain is scored on a scale from 0 to 100, with higher scores indicating better health and less limitation in that area. The SF-36 provides a comprehensive view of both physical and mental health.

Using the Epworth Sleepiness Scale (ESS). The ESS is a validated questionnaire that assesses daytime sleepiness by asking patients to rate their likelihood of falling asleep in eight common situations, such as sitting and reading or watching television. Each situation is rated on a scale from 0 (would never doze) to 3 (high chance of dozing), with a total score ranging from 0 to 24. Higher scores indicate greater levels of daytime sleepiness, which may affect daily functioning.

Using the Pittsburgh Sleep Quality Index (PSQI). The PSQI measures sleep quality and disturbances over a 1-month period. It consists of 19 items grouped into seven components: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep medication, and daytime dysfunction. Each component is scored from 0 to 3, and the component scores are summed to produce a global score ranging from 0 to 21. Higher scores indicate poorer sleep quality.

Using the Crohn's and Ulcerative Colitis Questionnaire-8 (CUCQ-8). The CUCQ-8 is a short, validated questionnaire used to assess the symptom burden in patients with Crohn's disease and ulcerative colitis. It consists of eight items that evaluate key symptoms such as abdominal pain, bowel urgency, and the frequency of bowel movements. Each item is scored on a scale from 0 (no symptoms) to 4 (severe symptoms), with a total score ranging from 0 to 32. Higher scores indicate a greater burden of gastrointestinal symptoms.

Sit to stand-5 test (STS-5). The test consists of going from a seated to a standing position 5 times as quickly as possible.

Sit to stand-60 test (STS-60). The test consists of going from a seated to a standing position as many times as possible within 60 seconds.

Using the Incremental Shuttle Walk Test (ISWT). The ISWT is a standardised field test used to assess functional exercise capacity. Patients walk back and forth along a 10-meter course, with the walking speed progressively increasing according to audio signals. The test continues until the patient is unable to keep up with the pace, becomes breathless, or reaches 85% of their age-relative maximum heart rate. The total distance walked is recorded and used to evaluate changes in exercise capacity. Greater distances indicate improved functional capacity and physical fitness.

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Via tanita body composition scales (bio electrical impedance analysis).

All participants will wear an Actigraph activity monitor on their non-dominant wrist to record physical activity for 7 days in the two weeks before the baseline assessment visit to characterise physical activity levels.

The Freedson (1998) activity monitor counts per minute cut points will be used to quantify minutes per day spent sedentary.

All participants will wear an Actigraph activity monitor on their non-dominant wrist to record physical activity for 7 days in the two weeks before the baseline assessment visit to characterise physical activity levels.

The Freedson (1998) activity monitor counts per minute cut points will be used to quantify minutes per day spent in light activity.

All participants will wear an Actigraph activity monitor on their non-dominant wrist to record physical activity for 7 days in the two weeks before the baseline assessment visit to characterise physical activity levels.

The Freedson (1998) activity monitor counts per minute cut points will be used to quantify minutes per day spent in moderate to vigorous physical activity.