Author: Clare Flower
Flower, Clare, 2024 Low energy availability in elite female athletes: risks and remediation, Flinders University, College of Nursing and Health Sciences
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Background
Low energy availability (LEA) occurs due to a mismatch between energy intake and energy expenditure. Consequently, there is inadequate energy to support basic physiological functions. Leanness sport athletes can be at risk of LEA due to high energy expenditure during training and competition, and restricted dietary intake. These athletes often face pressure to maintain a lean physique, leading to a preoccupation with maintaining a lean body composition, achieved through restriction of dietary energy intake.
Research on LEA has primarily focused on sports that emphasise a lean body physique, however athletes from other sports may also be at risk of LEA. This PhD project involved a comparison of endurance, aesthetic, and team sports athletes. The aims were to identify the prevalence and manifestation of LEA in these sports as well as testing the effectiveness of a ‘Food First’ motivational interviewing (MI) intervention to remediate LEA.
Methods
This project comprised four studies involving a literature review, validation of a dietary supplements intake questionnaire and a pilot study to trial a qualitative investigation into determinants of food choice among a range of athletes from different sports. These studies were used to inform the fourth study investigating LEA prevalence and the effectiveness of a ’Food First’ MI intervention.
Dietary intake, exercise energy expenditure and body composition were all measured at baseline and completion of the study to calculate energy availability (EA). Participants with LEA at baseline received the intervention (‘Food First’ personalised MI) and others received a general sports nutrition infographic as a control. A dietary supplements intake questionnaire (developed in chapter 3) was completed by all participants to assess the contribution of dietary supplement intakes to nutrition status. The MI intervention aimed to address LEA and correct any nutrient deficiencies identified through changes to dietary intake without reliance on supplements.
Results
Results demonstrated that LEA was prevalent among all sports, not just sports focused on a lean body composition such as endurance and aesthetic sports. The manifestation of LEA was investigated through the analyses of nutrient and food group intakes which showed that athletes with LEA commonly had low carbohydrate and inadequate dairy food intakes. The intentional or unintentional restriction of these foods were linked to the occurrence of LEA across each of the sports groups. Complementary qualitative data indicated the main influences on food choice were external including family, friends and demands of their sport. The MI intervention was successful in increasing the energy availability of athletes with LEA from all sports, but not enough to surpass the LEA threshold of 30 kcal.kg FFM.dy-1.
Conclusion
Further research is required to improve the ’Food First’ MI intervention to successfully remediate LEA in female athletes. Athletes may require more education on the importance of adequate dietary intake, particularly carbohydrate rich foods and dairy foods. The intervention may need to be extended to family and friends as major influencers on food choice and to allow for more sessions with each athlete to provide further education and follow-up on their progress.
Keywords: LEA, low energy availability, RED-s, relative energy deficiency in sport, female athletes
Subject: Nutrition and Dietetics thesis
Thesis type: Doctor of Philosophy
Completed: 2024
School: College of Nursing and Health Sciences
Supervisor: Dr Kathryn Jackson