How Super-Athletes Use FAT for Fuel

In this episode, we discuss fat through the lens of performance and survival, and what happens when we push our energy systems to their limits. We also talk about how our bodies make adaptations via exercise to improve our ability to “burn” fat for fuel, and how our bodies conserve fuel during times of negative energy balance. Lastly, we preview the role of fat as an endocrine organ and the importance of its communication with the brain, as well as the critical role of exercise capacity for our future health.

Chapters

00:00 – Introduction
01:49 – Extreme Endurance
02:54 – Fuel Source & Effort
03:12 – Glycogen
05:16 – Using Fat for Fuel
08:48 – Known Limits of Prolonged Energy Expenditure
10:21 – Metabolic Rate & Endurance Duration
14:00 – Physiology of Fat
16:18 – Insulin & Catecholamines in Fat Metabolism
19:10 – Fat as an Endocrine Organ
21:05 – Exercise & Maximal Fat Oxidation
22:02 – Exercise & Future Health
22:55 – Summary

References

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  3.  Carey, Daniel G. 2009. “Quantifying Differences in the ‘Fat Burning’ Zone and the Aerobic Zone: Implications For Training.” Journal of Strength and Conditioning Research / National Strength & Conditioning Association 23 (7): 2090.
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  7.  Thurber, Caitlin, Lara R. Dugas, Cara Ocobock, Bryce Carlson, John R. Speakman, and Herman Pontzer. 2019. “Extreme Events Reveal an Alimentary Limit on Sustained Maximal Human Energy Expenditure.” Science Advances 5 (6): eaaw0341.
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  9.  Frandsen, J., F. J. Amaro-Gahete, A. Landgrebe, F. Dela, J. R. Ruiz, J. W. Helge, and S. Larsen. 2021. “The Influence of Age, Sex and Cardiorespiratory Fitness on Maximal Fat Oxidation Rate.” Applied Physiology Nutrition and Metabolism 46 (10): 1241–47.
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  12.  Ravussin, Yann, Cuiying Xiao, Oksana Gavrilova, and Marc L. Reitman. 2014. “Effect of Intermittent Cold Exposure on Brown Fat Activation, Obesity, and Energy Homeostasis in Mice.” PloS One 9 (1): e85876.
  13.  Wang, Zhichao, Tinglu Ning, Anying Song, Jared Rutter, Qiong A. Wang, and Lei Jiang. 2020. “Chronic Cold Exposure Enhances Glucose Oxidation in Brown Adipose Tissue.” EMBO Reports 21 (11): e50085.
  14.  Brown, Aaron C. 2022. “Chapter 4 – Insights into the Adipose Stem Cell Niche in Health and Disease.” In Scientific Principles of Adipose Stem Cells, edited by Lauren Kokai, Kacey Marra, and J. Peter Rubin, 57–80. Academic Press.