Figure 2.

Chest wall strapping (CWS) and obesity induced breathing at low lung volumes. (A) The degree of expiratory reserve volume (ERV) reduction via CWS (open circles) or voluntary low–lung volume breathing (LLVB) for 2 minutes (solid circles) is correlated the slope of the 30–10% (of control vital capacity) portion of the flow–volume curve (as a surrogate for expiratory airflow—greater slope correlates with higher airflows). Reproduced with permission from Douglas and colleagues (4). (B) The exponential regressions for ERV as a function of body mass index (BMI). Reproduced by permission from Reference 22. FVL = flow-volume loop.