4th International Conference on Ambulatory Monitoring of Physical Activity and Movement (Limerick, Ireland, 10–12 June 2015)

In 2015 the 4th International Conference on Ambulatory Monitoring of Physical Activity and Movement (ICAMPAM2015) (www.ismpb.org/limerick-2015/) was held at the University of Limerick, Ireland, hosted by the International Society for the Measurement of Physical Behaviours (ISMPB) (www.ismpb.org/), and Chaired by Professor Alan Donnelly. The conference attracted over 200 oral and poster presentations from delegates whose interests were in the measurement of physical behaviours including physical activity, sedentary behaviour and sleep. The conference series provides a catalyst for research, attracting attendees representing academic communities and commercial concerns from across Europe, North and South America, Africa, the Middle East, Asia, Australia and New Zealand. Following ICAMPAM2015 the ISMPB continues the relationship with Physiological Measurement in publishing selected full articles from conference submissions in a focus issue of the journal. Previous focus issues include those from ICAMPAM2011, Glasgow Caledonian University, Glasgow, UK (www.ismpb.org/glasgow-2011/) and ICAMPAM2013, University of Massachusetts Amherst, USA (www.ismpb.org/history/2013-amherst/). For the ICAMPAM2015 focus issue the Guest Editors have selected articles covering the range of topics included at ICAMPAM2015. These articles represent the typical scope of content at an ICAMPAM conference; extending knowledge in the area of the measurement and characterisation of physical behaviours, whilst also exploring applications of this knowledge in health and disease: The automatic detection of sleep/waking time continues to be an important concern in fully characterising physical behaviour across 24 h periods (McVeigh et al 2016, Winkler et al 2016). Our developing understanding of the importance of sedentary behaviour was reflected in contributions to enhance detection and characterisation of this aspect of behaviour (Clarke-Cornwell et al 2016, Lerma et al 2016). Technological developments, especially the development of miniaturised wearable devices provide opportunities for enhanced data collection and a subsequent requirement for the demonstration of the validity and relevance of outcome measures. Within this focus issue the strength of contributions in this area to ICAMPAM2015 can be seen in a selection of articles (de Mullenheim et al 2016, Del Din et al 2016, Hislop et al 2016, Kheirkhahan et al 2016, Mackintosh et al 2016, Montoye et al 2016, Powell et al 2016, Rabuffetti et al 2016, Straczkiewicz et al 2016). Whilst accelerometry has been used extensively over many years to quantify human movement we now have the possibility to capture contextual information on physical behaviours using novel technologies (Loveday et al 2016). Thus new insight can inform and direct possible interventions to modify physical behaviour. The application of physical behaviour monitoring in the context of public health assessment and within clinical cohorts continues to provide invaluable insight into the impact of physical behaviour on health in B Stansfield et al