Manual therapy techniques targeting the thoracic region are commonly used in clinical practice. It has been suggested that manual therapy interventions directed at the spine can increase mobility of the spine and chest wall, which may have a positive impact on lung functions. The potential positive effects of thoracic manipulation on respiratory system diseases such as chronic obstructive pulmonary disease (COPD) and asthma have been investigated and continue to be studied. Specifically, the results of studies investigating the physiological outcomes of this therapeutic approach in healthy adults are conflicting. The aim of this study is to investigate the short-term effects of thoracic manipulation and mobilization, as well as diaphragm mobilization, through a single session of manual therapy interventions on respiratory functions.

In this planned study, designed as a randomized controlled intervention trial, two groups will be formed: an experimental group and a control group. After completing these procedures, the intervention group will receive the method of "thoracic mobilization and manipulation with diaphragm mobilization," while the control group will receive a placebo thoracic mobilization method. All techniques will be applied by a physiotherapist.

Within 5 minutes after the completion of the intervention, a respiratory function test will be repeated, resulting in a total of two respiratory function tests: one before the intervention and one after the intervention. The changes in respiratory function criteria before and after the intervention will be compared in both groups

Inclusion Criteria:

• be between the ages of 18-25,
• to be a studen

Exclusion Criteria:

• those who have any health problems
• those with orthopedic disorders
• those with systemic and cardiopulmonary diseases that would interfere with the evaluation