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. 2025 Sep 26;13(9):23259671251380877.
doi: 10.1177/23259671251380877. eCollection 2025 Sep.

Low-Energy Availability Indicators Among Female Adolescents After Concussion: A Comparison With Uninjured Controls

Katherine L Smulligan  1 , Aubrey M Armento  2   3 , Madison L Brna  4 , William P Meehan 3rd  1 , Julie C Wilson  2   3   5 , David R Howell  2   3
Affiliations

Low-Energy Availability Indicators Among Female Adolescents After Concussion: A Comparison With Uninjured Controls

Katherine L Smulligan et al. Orthop J Sports Med. .

Abstract

Background: After concussion, metabolic disruption causes a mismatch between the brain's energy demand and the body's ability to deliver energy to the brain. Physical activity (ie, energy expenditure) is recommended after concussion to facilitate recovery. Low-energy availability (LEA) is defined as inadequate energy available to support physiologic function after accounting for exercise energy expenditure and may influence concussion symptoms or disrupt/prolong recovery.

Purpose/hypothesis: The purpose was (1) to investigate LEA indicators (LEA-I) among female adolescents with and without recent concussion and (2) to examine the relationship between LEA-I and concussion symptom severity. It was hypothesized that (1) participants with concussion would have higher LEA-I than controls and (2) LEA-I and concussion symptom severity would be moderately correlated.

Study design: Cross-sectional study; Level of evidence, 3.

Methods: Two groups of female adolescents ages 13 to 18 years completed the Low Energy Availability in Females Questionnaire (LEAF-Q): uninjured controls and adolescents within 21 days of concussion. The LEAF-Q evaluates gastrointestinal symptoms, menstrual function, and injury frequency (range, 0-25). LEA-I was defined as scores ≥8, indicative of high LEA risk. Participants with concussion rated symptoms using the Post-concussion Symptom Inventory (PCSI; range, 0-120), with higher scores indicating more severe symptoms. We used independent samples t tests and calculated effect sizes to examine LEAF-Q between-group differences and linear regression for a multivariable comparison. For the concussion group, the correlation between LEAF-Q and PCSI scores was examined via Pearson r coefficients.

Results: We enrolled 117 female adolescents: 88 controls (mean ± SD age, 15.9 ± 1.5 years) and 29 with concussion (age, 15.5 ± 1.4 years). Upon univariable analysis, the concussion group reported significantly higher LEAF-Q scores than controls (9.1 ± 4.0 vs 6.0 ± 3.7; P < .001; Cohen d = 0.81). After adjusting for age and body mass index, LEAF-Q scores were 3.23 points higher on average for the concussion group as compared with controls (β = 3.23; 95% CI, 1.49-4.96; P < .001). For the concussion group, there was a small and insignificant correlation between LEAF-Q and PCSI scores (r = -0.06, P = .74).

Conclusion: Female adolescents after concussion had LEAF-Q scores indicative of high LEA risk, while controls did not. The lack of correlation between LEAF-Q and PCSI scores suggests that LEA-I is not associated with concussion symptoms.

Keywords: REDs; assessment; athlete health; brain injury.

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Conflict of interest statement

One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01HD108133) and the Denver Broncos Foundation. W.P.M. receives royalties from ABC-Clio Publishing, Springer International, and Wolters Kluwer and has received a grant from the National Football League. J.C.W. is a network team physician for US Soccer. D.R.H. has received research support from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (R03HD094560), the National Institute of Neurological Disorders and Stroke (R01NS100952, R43NS108823), the National Institute of Arthritis and Musculoskeletal and Skin Diseases (1R13AR080451), 59th Medical Wing Department of the Air Force, MINDSOURCE Brain Injury Network, the Tai Foundation, and the Colorado Clinical and Translational Sciences Institute (UL1 TR002535-05). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto. Ethical approval for this study was obtained from the University of Colorado.

Figures

Box plot with individual data points (jittered) demonstrating the distribution of LEAF-Q scores between the control and concussion groups. Data are presented as —— (line), —— (box), and —— (dashed lines). LEAF-Q, Low Energy Availability in Females Questionnaire.
Figure 1.
Box plot with individual data points (jittered) demonstrating the distribution of LEAF-Q scores between the control and concussion groups. Data are presented as median (line) and interquartile range (box). LEAF-Q, Low Energy Availability in Females Questionnaire.
The scatter plot titled “Scatter plot and line of best fit demonstrating the relationship between LEAF-Q and Post-concussion Symptom Inventory scores for the concussion group” shows the relationship between LEAF-Q and Post-concussion Symptom Inventory (SCI) scores. LEAF-Q, Low Energy Availability in Females Questionnaire
Figure 2.
Scatter plot and line of best fit demonstrating the relationship between LEAF-Q and Post-concussion Symptom Inventory scores for the concussion group. Shaded area indicates 95% CI. LEAF-Q, Low Energy Availability in Females Questionnaire.
See this image and copyright information in PMC

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