Assessment of Pain Perception and the Impact of Central Sensitization on Biopsychosocial Manifestations During Physical Activity in Patients With Chronic Low Back Pain

The goal of this prospective observational study is to evaluate changes in cognitive and behavioural markers associated with central sensitisation between the start and end of an exercise retraining programme on an exercise bike, in adult patients suffering from chronic lower back pain associated with an untreated degenerative spine, worth or without referred pain. The main changes it will evaluate are: \- Changes in cognitive and behavioural markers associated with central sensitisation between Day 0 and Day 40 during exercise retraining on an exercise bike as part of a rehabilitation programme for chronic low back pain Participants will undergo the followings: * A calibration test used to define moderate exertion on an ergocycle, corresponding to a perceived exertion of 4-5/10 on the modified Borg scale * Exercise-induced pain intensity assessment tests to detect changes in the intensity of pain during physical activity and the activity's potential to cause pain, realised on ergocyle * Exercise rehabilitation on an ergocycle * Final tests to assess cognitive and behavioural markers related to central sensitisation and pain intensity, as at baseline.