The effect of sitting and calf activity on leg fluid and snoring

Research output: Contribution to journalArticle



  • Bhajan Singh
  • Azadeh Yadollahi
  • Owen Lyons
  • Hisham Alshaer
  • T. Douglas Bradley

Research units


Prolonged sitting may promote leg fluid retention that redistributes to the neck during sleep and contributes to snoring. This could be attenuated by calf activity while sitting. In 16 healthy non-obese subjects we measured leg fluid volume (LFV) below the knees using bioelectrical impedance while sitting for 4 h, snoring using a portable BresoDx™ device, and Mallampati grade. Using a double cross-over study design, subjects were randomized to one of two arms and crossed-over one week later: control arm – no calf exercise while sitting; intervention arm – calf contraction against a pedal resistance while sitting. The effects of sitting ± calf activity on LFV and snoring were compared. We found that LFV increased by 216 ± 101.0 ml (p < 0.0001) after sitting. Calf activity while sitting attenuated LFV by 53.8 ml (p < 0.0001) and, in all five subjects with severe upper airway narrowing (Mallampati grade IV), reduced snoring duration (from 357 ± 132.9 to 116.2 ± 72.1 s/h, p = 0.02) suggesting reduced overnight rostral fluid shift to the neck.

Original languageEnglish
Pages (from-to)1-7
Number of pages7
JournalRespiratory Physiology and Neurobiology
StatePublished - 1 Jun 2017

View connections

ID: 13579380