Optoelectronic plethysmography (OEP) in the assessment of dysfunctional breathing (DB) in athletes

Introduction: Muscle recruitment and motor pattern are important not only to preserve intra-abdominal pressure but also to optimise biomechanical functions. A deviation away from the optimal trunk lumbo-pelvic recruitment pattern can affect the pressure, the ventilatory volumes, the stability and ultimately the work of breathing.

Aims and objectives: The aim of the study was to investigate the effect of different postural positions on the respiratory system using optoelectronic plethysmography (OEP) and a breath-by-breath (BbB) analyser.

Methods: Five healthy male athletes (Mean +/- SD age: 31.2±5.6 yrs.) completed the study protocol. They performed a 10-minute submaximal exercise test in two conditions (with hunched shoulders and with normal shoulder position) while undergoing simultaneous OEP and BbB data collection. Tidal volume (VT), breathing frequency (BF) and minute ventilation (VE) were assessed by the BbB analyser and data was gathered on the chest wall volume (CW) and the compartmental volumes of the rib cage (RC) and the abdomen (AB) by OEP.

Results: With the BbB analyser we detected a difference in tidal volume (VT) between the 'normal' and 'hunched' positions (2.94±0.84 l vs. 2.69±0.79 l; p=0.05) in the last stage of the 10-minute cycling test. This difference was detected also by the OEP system when CW contributions in the two conditions were compared (3.45±0.82 vs. 2.97±0.72; p=0.02). The other values remained unchanged.

Conclusions: Respiratory parameters may be affected during exercise by the postural positions of the shoulders leading to impaired chest wall movement and decreased tidal volumes. OEP may be a useful tool to assess altered parameters associated with DB.