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Updated: Jun 11, 2025

Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Dietary intake, energy availability, and power in men collegiate gymnasts
Nicholas M Kuhlman1, Margaret T Jones2,3, Andrew R Jagim2,4
1Department of Nutritional Sciences, University of Connecticut, Storrs, CT, United States.
Introduction:
The purpose was to examine the prevalence of low energy availability (LEA), explore dietary behaviors in men collegiate gymnasts (n = 14), and investigate the relationships between energy availability (EA), body composition, and plyometric performance.
Methods:
Body composition was measured using air displacement plethysmography. Lower- and upper-body peak power (PWRpeak) and modified reactive strength index (RSImod) were calculated from countermovement jump (CMJ) and plyometric push-up (PP) assessments. Energy expenditure was tracked over 3 days, while daily energy and macronutrient intake were recorded. EA was calculated and used to categorize athletes into LEA and non-LEA groups. Pearson correlation coefficients were used to examine relationships between EA, body composition, and performance metrics.
Results:
85.7% of athletes (n = 12) exhibited LEA (20.98 ± 5.2 kcals/kg FFM), with non-LEA athletes (n = 2) marginally surpassing the <30 kcal/kg of fat-free mass (FFM) threshold (30.58 ± 0.2 kcals/kg FFM). The cohort (n = 14) consumed insufficient energy (30.5 ± 4.5 kcal/kg/day) and carbohydrates (3.7 ± 1.1 g/kg/day), resulting in LEA (22.36 ± 5.9 kcal/kg/FFM). EA was not correlated with body composition or performance metrics.
Discussion:
A high prevalence of LEA may exist in men gymnasts, largely due to a low relative energy and carbohydrate intake.
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