Study four: A small scale RCT will be conducted to pilot the swimming lessons developed in study three, to compare the lessons to standard physiotherapy care and to assess the feasibility of conducting a large RCT in the future. The results from this feasibility study will give the researcher some initial feedback on the swimming lessons and will inform and support the development of an RCT in the future; if the initial findings are positive. This will include whether an RCT can be carried out and evaluating recruitment and retention rates, willingness to be randomised, adverse events, outcomes, acceptability and cost analysis.

Low back pain is very common; globally it is the number one cause of disability. National guidelines recommend exercise for the management of back pain; swimming is frequently advised despite little supporting evidence. Swimming is considered to be low impact and might target conditions associated with back pain such as obesity, inactivity, and depression. Swimming lessons are not funded by the NHS, many adults cannot swim and there are no guidelines regarding what type of swimming program to recommend.

This multi-phase mixed methods research project aims to develop a swimming class to be used as a form of rehabilitation for persistent low back pain. There are many barriers to exercise and this can affect uptake and adherence; Study 1 will be an online survey finding out what stops and what encourages people with back pain to go swimming. Some people already use swimming to manage back pain; in Study 2, individuals who use swimming to manage back pain will be interviewed to explore their experience including discussion about swimming stroke and adaptations. The swimming class will be developed in Study 3 using the data from Study 1 and 2 and by consulting physiotherapists, swimming teachers, and patients, through a series of surveys, known as the Delphi method. Study 4 will be a feasibility study; comparing the swimming class developed in Study 3 over 3 weeks to standard physiotherapy care. Data will be collected on the running of the study, outcomes including function and quality of life, with further follow up at on completion of the trial and 6 months. These studies will be carried out at East Kent Hospitals NHS Trust and the Hotel Burstin swimming pool; people with back pain for more than 3 months would be eligible to take part.

Inclusion Criteria:

• The inclusion criteria for the study were that participants should have experienced CLBP for more than three months, be at least 18 years old and have a small amount of swimming experience.

Exclusion Criteria:

• Exclusion criteria for the study included the following: unable to read or speak English, allergy to chlorine, severe fear of the water, pregnancy, ear infection, already a competent regular swimmer, visual impairment not correctable with glasses, medical contraindication to aquatic exercise or precaution that cannot be resolved. The following back conditions were excluded; red flag conditions (cauda equina syndrome, cancer or tumour related back pain, spinal infection, spinal cord compression, back pain from visceral source), inflammatory back pain, fractures of the spine during the last 6 months, severe spinal stenosis, nerve root compromise causing neurological deficit or constant pain in the leg, back surgery in the last 6 months, and fitted with a spinal cord stimulator.

There is no plan but we are happy to share data with other researchers