Abstract
Purpose of Review
Low energy availability (EA) poses severe consequences to athlete performance and overall health. Suppressed resting metabolic rate (RMR) has been observed during periods of low EA. Thus, it has been suggested that the ratio of RMR measured via indirect calorimetry to predictive RMR using a standard predictive equation (RMR ratio) may be a useful assessment of EA in athletes. This review evaluated the use of RMR ratio as a surrogate marker for low EA in athletes and compared methodologies for measuring RMR ratio.
Recent Findings
Decreased RMR ratio in recent studies often correlates with signs of low EA; however, athletes with less severe cases of energy deficiency may not present with a low RMR ratio. Additionally, the methodology for RMR ratio measurements lacks standardization and varies in recent studies.
Summary
Use of RMR ratio has promise as a complementary EA measurement when used in combination with other assessment tools.
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References
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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Trisha Sterringer and D. Enette Larson-Meyer declare they have no conflicts of interests.
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Sterringer, T., Larson-Meyer, D.E. RMR Ratio as a Surrogate Marker for Low Energy Availability. Curr Nutr Rep 11, 263–272 (2022). https://doi.org/10.1007/s13668-021-00385-x
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DOI: https://doi.org/10.1007/s13668-021-00385-x