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תלמיד המחלקה לתואר שני ירצה בנושא:

New Device and Method for Measuring the Anaerobic Threshold

Background: The anaerobic threshold (AT) is used to assess the subject’s ability to perform long-term aerobic exercise. AT is useful in endurance fitness training as an indicator for the level of fitness. Furthermore, AT monitoring is vital for rehabilitation of cardiac patients. Currently, the sole method for the detection of AT is performed in the laboratory and involve clinical staff. Aim: To develop a new device and method for the detection of AT in the field. Methods: A prototype (AT strap) was built of a chest belt combining vertical accelerometry and heart rate monitoring for the assessment of exercise intensity together with a new developed stretch sensor for measuring pulmonary ventilation (equivalent of). All sensors were connected to a data processing and logging unit. The stretch sensor was characterized, and compared with the Biopac respiration sensor and Cosmed pulmonary function equipment. Breath simulations have been made with the stretch sensor, in order to test the sensor output by the changes in RR (0.2-1 Hz) and the change in the equivalent of the tidal volume (TV) evaluated by thorax expansion. Cardiopulmonary exercise stress Tests (CPET, ZAN 600) were conducted using the AT strap to compare between the two methods. RR and AT results were compared using Bland–Altman Analysis. Results: Initial stretch sensor’s optimal length has been determined at 12 cm stretching up to 20 cm, using 3 stretch sensors in parallel for signal stabilization. RR tests (N=74) results have show high agreement between methods (mean difference: 0.2 [1/min], Limits of agreement 95% (LoA): -2.7 - 3.2 [1/min]). Increase in amplitude of stretch sensor signal has been noted with the linear thorax expansion in the breath simulation. Results were consistent in all RRs tested (0.2-1 Hz). AT results have been tested (still ongoing, so far N=6) in comparison with a CPET results (mean difference: 0.52 [watt], LoA: -8.16 - 9.21.2 [1/min]). Conclusions: The proposed stretch sensor successfully detects pulmonary attributes (RR, relative TV) relevant to the AT detection method. High agreement has been detected between AT strap and CPET results. Additional tests should be taken to successfully validate the agreement between both devices under a larger and more diverse individuals and patients.

העבודה נעשתה בהנחייתו של פרופ' מיקי שיינוביץ, המחלקה להנדסה ביו-רפואית,

אוניברסיטת תל-אביב

ההרצאה תתקיים ביום ראשון 17.6.2012, בשעה 15:15,

בחדר 315, הבניין הרב תחומי, אוניברסיטת תל אביב