PT  - JOURNAL ARTICLE
AU  - Zuidema, Menno J.
AU  - Hartman, Jorine E.
AU  - ten Hacken, Nick H.T.
AU  - de Greef, Matthieu H.G.
AU  - van Lummel, Rob C.
TI  - Use of accelerometers for measuring consecutive bouts in physical activity recommendations
DP  - 2011 Sep 01
TA  - European Respiratory Journal
PG  - p2179
VI  - 38
IP  - Suppl 55
4099  - http://erj.ersjournals.com/content/38/Suppl_55/p2179.short
4100  - http://erj.ersjournals.com/content/38/Suppl_55/p2179.full
SO  - Eur Respir J2011 Sep 01; 38
AB  - Background: Most recommendations for physical activity (PA) are based on subjective self reported measures, although performance-based accelerometers are already available for many years. To meet PA recommendations, subjects need to be physically active in bouts varying from 5 to 20 minutes. However, the influence of bout length and bout interruptions in objectively measured PA status is not exactly known.Aim: The aim of the present study is to investigate the effect of different consecutive bout lengths and bout interruptions on the PA status using accelerometers.Methods: Twenty COPD patients were selected from a larger dataset, based on a large range in PA level. The DynaPort accelerometer (100Hz, ±2g, McRoberts BV, The Hague, the Netherlands) was used for measuring PA during a full week of daily living. Systematically varied bout lengths and interruptions are investigated to examine PA status.Results: Bout length of 10 versus 1 minute shows a 71% difference in PA status (91 METs·min vs 317 METs·min) (figure 1a). Bout interruption duration of 0 vs 5 minutes shows a 57% difference in PA status (91 METs·min vs 214 METs·min) (figure 1b).Conclusion: This study shows that varying bout length and interruption duration has large impact on PA status. When applying PA recommendations this should be taken into account, particularly in subjects with a sedentary life style.