Supervisors info:
Ρουσάνογλου Ελισσάβετ, Αναπληρώτρια Καθηγήτρια, Σχολή Επιστήμης Φυσικής Αγωγής και Αθλητισμού, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (επιβλέπουσα)
Γελαδάς Νικόλαος, Καθηγητής, Σχολή Επιστήμης Φυσικής Αγωγής και Αθλητισμού, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Μπουντόλος Κωνσταντίνος, Σχολή Επιστήμης Φυσικής Αγωγής και Αθλητισμού, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Summary:
Body posture as well as breathing type appear to have a significant effect on kinetic stability and respiratory muscle activity. The relevant studies do not examine postures that set the body in positions of particularly unstable equilibrium as the as the lateral and inverted supports. The purpose of this study was to examine the effect of body posture and abdominal breathing on the kinetic stability and the respiratory muscle activity in body postures of a variable degree of stability. Twenty-nine participants (age: 25.4 ± 7.8 years, height: 168 ± 0.08 cm and body mass: 62.8 ± 9.54 kg) maintained (40 sec) the quiet standing (QS), the inverted V support (IVS), the elbow side bridge (ESB) and the headstand (HS), using normal (ΝΒ) and abdominal breathing (ΑΒ), respectively (3 trials in each condition). A synchronized recording of the 2-dimensional characteristics of the center of pressure (Kistler Type 9281B11, Bioware, Software Kistler Instrument, Amherst, NY) and the activity of four respiratory muscles through the vibromyography method (VMG) (MEMS, MP150, ΑcqKnowledge software v. 5.0, Biopac Systems, Inc., Santa Barbara, CA) was made. (sternocleidomastoid: SCM, external intercostal: EX.I., diaphragm: DIA, rectus abdominis: RA). A 3-dimensional recording of angular changes of the abdominal wall (MicroStrain, 3DM-GX3®-45) was also performed to validate the use of AB. Statistical analysis aimed to test the effect of body posture (univariate analysis of variance separately in each breathing type) and the effect breathing type (univariate analysis of variance separately in each body posture), for the variables of kinetic stability and respiratory muscle activity (SPSS 25.0, p <0.05). Body posture appeared to have a significant effect on the kinetic stability and the respiratory muscle function (p ≤ 0.05). The lowest kinetic stability was observed in the HS (anteroposterior and lateral direction), while the highest one was observed in IVS (anteroposterior direction) and the ESB (lateral direction). The activity of the respiratory muscles was greater in ESB (EXI, DIA, RA) and the HS (SCM) and lower in the QS. AB appeared to have a significant negative effect on kinetic stability only during QS and HS (p ≤ 0.05). AB significantly increased the respiratory activation of the RA and the DIA (p ≤ 0.05) but not the activation of the SCM and the EXI (p> 0.05). In conclusion, body posture appears to have a significant effect on kinetic stability and respiratory muscle function, in non-everyday postures as the inverted and lateral supports which are used in popular exercise programs. HS is documented as a particularly demanding posture as it sets the body in a state of unstable equilibrium and increased respiratory muscle activity. The use of AB further increases the already unstable equilibrium of the HS, as the particular type of breathing inherently induces a destabilizing stimulus due to the demand for low muscular tension in the abdominal wall during the inhalation phase.
respiratory muscles in combination with the reduction of the activation of abdominal wall is an inherent destabilizing stimulus of that breathing type.
Keywords:
body posture, abdominal breathing, kinetic stability, respiratory muscles activity
