Effectiveness of a Quick Release Dynamic Muscle-strengthening Program on Dynamic Stabilization of the Cervical Spine

Participants will perform 20 minutes of isometric contractions in different positions, with contraction durations of 10 seconds and a number of repetitions between 4 and 10, depending on their progress in the training program.

"This training involves performing skill exercises with a rugby ball while wearing stroboscopic glasses. The glasses have alternating opaque and clear sections, causing multiple and/or fragmented vision.~The goal is to improve the processing of visual information at the level of higher functions. This aids in decision-making. It does not involve the same structures and functions implicated in reflexive muscle recruitment strategies as the Quick Release, so it should not be a confounding factor. However, it provides a beneficial, stimulating, and enjoyable training session, increasing subject adherence as they work on a skill useful in their sport."

"The distance (in mm) of the anterior head translation will be measured using a linear displacement sensor. The subject will be instructed to recruit their extensor muscles as quickly and as strongly as possible to minimise the head displacement distance. They will be aware of their score after each repetition (real-time feedback).~Subjects must react to a rapid forward displacement of the cervical spine, without impact. To generate this forward displacement without impact, subjects are positioned with support in front of the forehead, holding their head and neck. The subject must exert an isometric flexion effort against this frontal support (energy storage), with the intensity set by the examiner based on the Maximum Isometric Force measured during a prior maximal isometric test. The frontal resistance will suddenly release, and the head displacement in the sagittal plane will be measured until the recruitment of the cervical spine extensor muscles stops this displacement"