Participants will undertake a back school-based program. This program will follow the recommendations of the biopsychosocial model of chronic pain and will be conducted in an aquatic environment. The intervention will be carried out by physiotherapists in a sports center. The duration of the intervention will be six weeks, with a frequency of two sessions per week, totaling 12 sessions of 45 minutes each. Of all the sessions, 10 will have a practical focus (centered on trunk exercises) and the other two will have a theoretical focus (providing education on pain and risk factors for low back pain).

They will continue with their usual lifestyle.

Participants will undertake a back school-based program. This program will follow the recommendations of the biopsychosocial model of chronic pain and will be conducted in an aquatic environment. The intervention will be carried out by physiotherapists in a sports center. The duration of the intervention will be six weeks, with a frequency of two sessions per week, totaling 12 sessions of 45 minutes each. Of all the sessions, 10 will have a practical focus (centered on trunk exercises) and the other two will have a theoretical focus (providing education on pain and risk factors for low back pain).

The visual analogue scale is a widely used tool to measure pain. The patient is asked to indicate the intensity of the pain they perceive (most commonly) along a horizontal line from 0 millimetres (minimum value) to 100 millimetres (maximum value), and this score is then measured from the left edge, the higher the value in millimetres the more pain.

The Roland Morris Disability Questionnaire Scoring is a 24-item patient-reported outcome measure that inquires about pain-related disability resulting from LBP. Items are scored 0 if left blank or 1 if endorsed, for a total Roland Morris Disability Questionnaire score ranging from 0 to 24; higher scores represent higher levels of pain-related disability.

Short-Form Health Survey was used to measure quality of life.The Short-Form Health Survey-36 explores people's physical and mental health. It consists of 36 items that assessed eight dimensions of health status: social function, physical function, emotional role, physical role, mental health, vitality, physical pain, and general health. Scores ranged from 0 (worst health status) to 100 (best health status).

This scale measures kinesiophobia. The total scale score ranges from 11 to 44, where 11 means no kinesiophobia and 44 means severe kinesiophobia.