Commercial systems utilizing data from inertial measurement units (IMUs) to analyse movement patterns have not yet been adapted to monitor daily training in cross-country (XC) skiing. The main purposes of this study are to investigate: 1) the feasibility and potential of a multi-sensor system consisting of a heart rate sensor, Global Navigation Satellite Systems (GNSS) data and seven IMUs placed at multiple locations on the body for outdoor XC skiing, and 2) the validity of employing hard decision rules based on the correlation between arms and legs for detecting subtechniques in classical XC skiing. All sensor data were synchronously sampled and synchronized with GNSS data from a commercially available sports watch while XC skiing on varying tracks, from amateur skiers and world-class athletes. An algorithm based on the correlation of the angular velocity of arms and legs was developed to detect the three main classic sub-techniques, diagonal, double poling with a kick and double poling. Other sub-techniques were classified as miscellaneous (0−20%). The system is shown to work well outdoors on snow during different conditions, and the implemented algorithm was validated by video analyses to detect the three sub-techniques with a sensitivity of 99-100%. This study is the first to detect and link sub-techniques in XC skiing to GNSS data, thereby associating the detection and distribution of sub-techniques to different terrains. Such information gives insight on technical and tactical aspects of skiers' daily training and competitions, thereby providing a tool for coaches and athletes.

Abstract-Objective: One promising approach for a continuous, non-invasive, cuff-less ambulatory BP monitor is to measure the pulse wave velocity or the inversely proportional pulse transit time (PTT), based on electrical and optical physiological measurements in the chest area. A device termed IsenseU-BP+ has been developed for measuring continuous BP, as well as other physiological data. The objective of this paper is to present results from the first clinical evaluation with a wide range of patients. The study was set up to verify whether IsenseU-BP+ can be used to measure raw signals with sufficient quality to derive PTT. Methods: The test protocol, run 23 times on 18 different patients with non-alcoholic fatty liver disease, includes both supine measurement at rest as well as measurements during indoor cycling. Changes in PTT were compared with the BP changes measured using validated reference sensors. Results: IsenseU-BP+ measured signals with good quality during rest on 17 of 18 patients despite the high diversity in age, body shape and BMI. Evaluation during cycling was difficult due to a lack of good reference measurements. Conclusion: IsenseU-BP+ measures PTT with high quality during supine rest and exercise and could therefore be suitable for deriving non-invasive continuous BP, although evaluation during exercise was limited due to inaccurate reference BP measurements. Significance: Continuous, non-invasive measurement of BP would be highly beneficial in a number of clinical settings. Systems currently considered gold-standard for the investigation of hypertension carry considerable limitations which could be overcome by the method proposed here.Index Terms-cuff-less blood pressure, pulse transit time, pulse wave velocity, unobtrusive sensing, hypertension

No abstract

No abstract

Prehospital emergency triage involves prioritising patients and deciding who are in the most urgent need of treatment and medical intervention. Currently used triage methods do not support simple sharing of patient-related information, making it challenging for emergency personnel to monitor the number, location and medical status of patients involved in an incident. We present the design and evaluation of an electronic system that facilitates patient tracking and monitoring of vital parameters from the incident scene to place of treatment. The system comprises a patient electronic triage bracelet, which communicates with software applications for patient monitoring. We tested the system in two situations: real-life, daily operations involving real patients over 1 month and in a 1-day, large-scale, mass casualty exercises. Results are presented, along with lessons learned and suggestions for future research.