Effect of thoracic spine manipulation on pulmonary function in swimmers with asthma – a study protocol of a randomized controlled crossover trial.

This is a protocol study that will serve as a basis for conducting a randomized controlled crossover trial. This protocol study defines as objectives the analysis of the applicability of thoracic spine manipulation (TSM) and its effects on lung function in swimmers with asthma. Elite level athletes constantly seek methods to improve performance and these techniques can play a very important role in the treatment, recovery, and improvement of the functional capacity of the respiratory system. Twenty-six (26) participants will be randomly allocated into 2 groups, 13 participants in the intervention group (IG) and 13 participants in the control group, in which there will be 3 treatment sessions per week, totaling 6 treatments in 2 weeks, after which the groups will be crossed and the protocol will be repeated. The study will be carried out in the facilities of four swimming clubs where the participants will be recruited in the Lisbon region, Portugal. The intervention in both groups will be performed by the same osteopath with 13 years of experience in the TSM technique. Participants will be screened for eligibility inclusion and exclusion criteria, and where they must sign an informed consent and a questionnaire relating to personal, health, and nutritional data (or their legal representative). Participants in the IG will receive high velocity low amplitude (HVLA) technique or manipulation grade V applied to the thoracic spine where the following outcomes will be obtained: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF) at baseline and 1 minute after TSM, and cirtometry and pulse oximetry 4 minutes after FVC, FEV1 and PEF. The HVLA technique is applied as follows: The subject will lay supine with the arms crossed over the chest and hands passed around the shoulder. The thoracic spine will be in a neutral position. The hand of the osteopath will contact in a neutral hand position, first over the spinous process of T1-T3, and then over T4-T6. The other hand will stabilize the head, neck, and upper thoracic spine of the participant. Gently, flexion of the thoracic spine will be introduced until slight tension will be palpated in the tissues at the osteopath contact point. Then, an HVLA technique downward toward the couch and in a cephalad direction will be applied. A cracking or popping should accompany accompanied all manipulations. If no popping sound is heard on the first attempt, the osteopath will reposition the participant and perform a second HVLA thrust manipulation. A maximum of 2 attempts will be performed on each participant. The time spends to apply the protocol will be approximately 10 minutes. Subsequently, there will be a 2-week washout period, after which there will be the crossover of the groups and the protocol will be performed again in the same way.