Breathing pattern changes in response to bronchoconstriction in physically active adults

Objectives: To determine whether Opto-Electronic Plethysmography (OEP) can distinguish

Exercise-Induced Bronchoconstriction (EIB) breathing patterns by comparing individuals with

and without EIB, and between broncho-constriction and recovery. Breathing pattern was

quantified in terms of regional contribution, breathing timing, and the phase between chest

sub-compartments which indicates the synchronization in movement of the different

sub-compartments.

Methods: Individuals (n = 47) reporting no respiratory symptoms and no history of any

respiratory disease or disorder were assumed to have a healthy breathing pattern. Of 38

participants reporting respiratory symptoms during exercise, and/or a previous diagnosis of

asthma or EIB, 10 participants had a positive result to the Eucapnic Voluntary Hyperpnea test,

defined as a fall of at least 10% in FEV1 from baseline at two consecutive time points and

were classified into the EIB group. OEP data was obtained from 89 markers and an 11-camera

motion capture system operating at 100 Hz as follows: pre- and post-EVH challenge, and

post-inhaler in participants who experienced a bronchoconstriction, and 2) for the healthy

group during tidal breathing.

Results: RCpRCa-Phase (upper versus lower ribcage), RCaS-Phase (lower ribcage versus

shoulders), and RCpS-Phase (upper ribcage versus shoulders) differed between

bronchoconstriction and rest in athletes with EIB and rest in healthy participants (p < 0.05), in

all cases indicating greater asynchrony post-bronchoconstriction, and later movement of the

abdominal ribcage (RCa) post-bronchoconstriction. RCpS-Phase was different (p < 0.05)

between all conditions (rest, post-bronchoconstriction, and post-inhaler) in EIB.

Conclusions: OEP can characterize and distinguish EIB-associated breathing patterns

compared to rest and individuals without EIB at rest.