TY - JOUR
T1 - Field-deployable measurements of free-living individuals to determine energy balance
T2 - fuel substrate usage through δ 13 C in breath CO 2 and diet through hair δ 13 C and δ 15 N values
AU - Gordon, Gwyneth
AU - Rhoads, Amrita
N1 - Funding Information:
This study was funded by the ASU-Mayo Foundation Obesity Solutions program with support from the Virginia G. Piper Charitable Trust. This project was funded by a Seed Grant of this program. It has a child account number of ZBS 0036, with a Coeus award number of 025579-012. The grant contract accountant listed is Nicholas Petersen (480) 727-9458.
Funding Information:
This study was funded by the ASU-Mayo Foundation Obesity Solutions program with support from the Virginia G. Piper Charitable Trust. This project was funded by a Seed Grant of this program. It has a child account number of ZBS 0036, with a Coeus award number of 025579-012. The grant contract accountant listed is Nicholas Petersen (480) 727-9458. Dr. Erica Forzani (Biodesign Institute, Arizona State University) provided guidance in implementing the Breezing?. Dr. Glenn Gaesser (Healthy Lifestyles Research Center, Arizona State University) suggested modifications to the exercise program. We thank the participants for their generosity in time, assistance, discussions, and feedback about the study.
Publisher Copyright:
© 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.
PY - 2019/1/2
Y1 - 2019/1/2
N2 - Carbon isotopes of breath CO 2 vary depending on diet and fuel substrate used. This study examined if exercise-induced δ 13 C-CO 2 changes in substrate utilization were distinguishable from baseline δ 13 C-CO 2 variations in a population with uncontrolled diet, and compared hair isotope values and food logs to develop an isotope model of diet. Study participants included nine women with diverse Body Mass Index (BMI), age, ancestry, exercise history, and diet. Breath samples were collected prior to and up to 12 h after a 5- or 10 K walk/run. Indirect calorimetry was measured with a smartphone-enabled mobile colorimetric device, and a field-deployable isotope analyzer measured breath δ 13 C-CO 2 values. Diet was assessed by food logs and δ 13 C, δ 15 N of hair samples. Post-exercise δ 13 C-CO 2 values increased by 0.54 ± 1.09‰ (1 sd, n = 9), implying enhanced carbohydrate burning, while early morning δ 13 C-CO 2 values were lower than daily averages (p = 0.0043), indicating lipid burning during overnight fasting. Although diurnal δ 13 C-CO 2 variation (1.90 ± 0.77‰) and participant baseline range (3.06‰) exceeded exercise-induced variation, temporal patterns distinguished exercise from dietary isotope effects. Hair δ 13 C and δ 15 N values were consistent with a new dietary isotope model. Notwithstanding the small number of participants, this study introduces a novel combination of techniques to directly monitor energy balance in free-living individuals.
AB - Carbon isotopes of breath CO 2 vary depending on diet and fuel substrate used. This study examined if exercise-induced δ 13 C-CO 2 changes in substrate utilization were distinguishable from baseline δ 13 C-CO 2 variations in a population with uncontrolled diet, and compared hair isotope values and food logs to develop an isotope model of diet. Study participants included nine women with diverse Body Mass Index (BMI), age, ancestry, exercise history, and diet. Breath samples were collected prior to and up to 12 h after a 5- or 10 K walk/run. Indirect calorimetry was measured with a smartphone-enabled mobile colorimetric device, and a field-deployable isotope analyzer measured breath δ 13 C-CO 2 values. Diet was assessed by food logs and δ 13 C, δ 15 N of hair samples. Post-exercise δ 13 C-CO 2 values increased by 0.54 ± 1.09‰ (1 sd, n = 9), implying enhanced carbohydrate burning, while early morning δ 13 C-CO 2 values were lower than daily averages (p = 0.0043), indicating lipid burning during overnight fasting. Although diurnal δ 13 C-CO 2 variation (1.90 ± 0.77‰) and participant baseline range (3.06‰) exceeded exercise-induced variation, temporal patterns distinguished exercise from dietary isotope effects. Hair δ 13 C and δ 15 N values were consistent with a new dietary isotope model. Notwithstanding the small number of participants, this study introduces a novel combination of techniques to directly monitor energy balance in free-living individuals.
KW - Breath isotopes
KW - carbon isotopes
KW - energy balance
KW - exercise metabolism
KW - hair isotopes
KW - nitrogen isotopes
UR - http://www.scopus.com/inward/record.url?scp=85059558123&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85059558123&partnerID=8YFLogxK
U2 - 10.1080/10256016.2018.1562448
DO - 10.1080/10256016.2018.1562448
M3 - Article
C2 - 30602299
AN - SCOPUS:85059558123
VL - 55
SP - 70
EP - 79
JO - Isotopes in Environmental and Health Studies
JF - Isotopes in Environmental and Health Studies
SN - 1025-6016
IS - 1
ER -