J M Jakicic1, C Winters, K Lagally, J Ho, R J Robertson, R R Wing. 1. Obesity/Nutrition Research Center and Human Energy Research Laboratory, University of Pittsburgh, School of Medicine, PA 15213, USA. jjakicic@ukans.edu
Abstract
PURPOSE: This study examined the reliability and validity of the TriTrac-R3D triaxial accelerometer to estimate energy expenditure during various modes of exercise. METHODS: Twenty subjects (age = 21.5+/-3.4 yr; body mass index = 23.3+/-3.6 kg x m(-2)) performed five exercises (treadmill walking, treadmill running, stepping, stationary cycling, and slideboard), with each lasting 20-30 min and workload increased at 10-min intervals. To test the inter-TriTrac reliability, two TriTrac-R3D accelerometers were worn during each exercise period, and to examine validity, a simultaneous measurement of energy expenditure was made using indirect calorimetry (SensorMedics 2900 Metabolic Cart). RESULTS: Results showed a significant correlation between the two TriTrac-R3D accelerometers during all exercises. The difference in estimated energy expenditure between the two accelerometers during the walking, stepping, and slideboard exercises was less than 1 kcal x min(-1) but statistically significant (P<0.05). There was also a significant correlation between energy expenditure estimated by each of the TriTrac-R3D accelerometers and indirect calorimetry during walking, running, stepping, and slideboard exercise (P<0.05). The interaction of Method x Workload was significant (P<0.05) for each exercise, indicating that the TriTrac-R3D underestimates energy expenditure and that the magnitude of this underestimation increases as workload increases. CONCLUSIONS: Therefore, energy expenditure estimated via triaxial accelerometry does not increase with increasing workloads. These results suggest that there are limitations to using triaxial accelerometry to quantify energy expenditure.
PURPOSE: This study examined the reliability and validity of the TriTrac-R3D triaxial accelerometer to estimate energy expenditure during various modes of exercise. METHODS: Twenty subjects (age = 21.5+/-3.4 yr; body mass index = 23.3+/-3.6 kg x m(-2)) performed five exercises (treadmill walking, treadmill running, stepping, stationary cycling, and slideboard), with each lasting 20-30 min and workload increased at 10-min intervals. To test the inter-TriTrac reliability, two TriTrac-R3D accelerometers were worn during each exercise period, and to examine validity, a simultaneous measurement of energy expenditure was made using indirect calorimetry (SensorMedics 2900 Metabolic Cart). RESULTS: Results showed a significant correlation between the two TriTrac-R3D accelerometers during all exercises. The difference in estimated energy expenditure between the two accelerometers during the walking, stepping, and slideboard exercises was less than 1 kcal x min(-1) but statistically significant (P<0.05). There was also a significant correlation between energy expenditure estimated by each of the TriTrac-R3D accelerometers and indirect calorimetry during walking, running, stepping, and slideboard exercise (P<0.05). The interaction of Method x Workload was significant (P<0.05) for each exercise, indicating that the TriTrac-R3D underestimates energy expenditure and that the magnitude of this underestimation increases as workload increases. CONCLUSIONS: Therefore, energy expenditure estimated via triaxial accelerometry does not increase with increasing workloads. These results suggest that there are limitations to using triaxial accelerometry to quantify energy expenditure.
Authors: Kong Y Chen; Sari A Acra; Karen Majchrzak; Candice L Donahue; Lemont Baker; Linda Clemens; Ming Sun; Maciej S Buchowski Journal: Diabetes Technol Ther Date: 2003 Impact factor: 6.118
Authors: Victoria A Catenacci; Gary K Grunwald; Jan P Ingebrigtsen; John M Jakicic; Michael D McDermott; Suzanne Phelan; Rena R Wing; James O Hill; Holly R Wyatt Journal: Obesity (Silver Spring) Date: 2010-10-28 Impact factor: 5.002
Authors: John M Jakicic; Edward Gregg; William Knowler; David E Kelley; Wei Lang; Gary D Miller; F Xavier Pi-Sunyer; Judith G Regensteiner; W Jack Rejeski; Paul Ridisl; Michael P Walkup; Donna L Wolf Journal: Med Sci Sports Exerc Date: 2010-11 Impact factor: 5.411
Authors: Dane R Van Domelen; Paolo Caserotti; Robert J Brychta; Tamara B Harris; Kushang V Patel; Kong Y Chen; Nanna Ýr Arnardóttir; Gudny Eirikdottir; Lenore J Launer; Vilmundur Gudnason; Thórarinn Sveinsson; Erlingur Jóhannsson; Annemarie Koster Journal: J Phys Act Health Date: 2013-02-08
Authors: Sander M Slootmaker; Albertine J Schuit; Marijke Jm Chinapaw; Jacob C Seidell; Willem van Mechelen Journal: Int J Behav Nutr Phys Act Date: 2009-03-25 Impact factor: 6.457