Relative Energy Deficiency in Sport (RED-S) characterizes a range of negative health and performance outcomes that result from chronically low energy availability. RED-S concerns high performance junior and senior athletes across Canada and has a prevalence rate of 3-60%. Our ability to assess and diagnose RED-S remains poor. Accordingly, we aim to create the best parameters to diagnose and manage RED-S; along with information of the prevalence and severity across Canada and globally. These outcomes are expected to have a significant positive impact on the health and performance of Canadian athletes in preparation for the Olympic Games in 2022 and beyond.

Purpose:

Our aim is to improve our understanding of the prevalence and symptoms of RED-S in international and Canadian athletes and para-athletes, along with developing screening tools and treatment protocols to manage RED-S in order to improve athlete health, availability and performance.

Objectives:

1. Assess the prevalence of self-reported RED-S health outcomes in international and Canadian elite female and male athletes and para-athletes as well as recreational athletes (Study A);
2. Assess the prevalence and severity of measured standard/basic RED-S health outcomes including biomarkers and potential longitudinal (6-mo) tracking of outcomes across the Canadian Olympic and Paralympic Sport Institute Network (COPSI) (Study B);
3. Implement a more advanced assessment, using novel RED-S assessment parameters in a smaller cohort of key athletes, including potential longitudinal tracking over a 6-mo period (Study C);
4. Assess longitudinal changes and the treatment of RED-S symptoms across a 6-month follow-up period in a small cohort of elite Canadian athletes willing to partake in an 'holistic' RED-S treatment intervention arm (Study D);
5. Utilize the data created from Studies A,B,C,and D to develop and validate potentially novel RED-S assessment parameters in order to further validate the 'new' IOC RED-S clinical assessment tool (CAT) version 2 to aid in the diagnosis of RED-S.

Justification:

This study will be the first to systematically assess the prevalence and severity of outcomes of RED-S in a large group of international and Canadian athletes and para-athletes (A), and within the COPSI network (B,C), utilising physiological and performance tests and training metrics for a more holistic assessment of potential outcomes (B,C,). This study will also aim to strengthen the literature regarding to the time-course of changes in these outcomes (B,C,D) and the efficacy of a simple nutritional intervention arm on these changes (D). Finally, this multicentre project will be the largest to date in Canada and globally, and the first to produce data on the prevalence of RED-S within the COPSI network (across A,B,C,D).

Research Design:

This is an observational study including online survey and physiological testing with potential for follow-up in a subset of athletes. A separate study arm (study D) will be an intervention arm with follow-up.

Statistical analysis:

Analysis will be a combination of basic statistics such as t-tests and ANOVA's, as well as more advanced statistical modelling (e.g. stepwise regression modelling, with first identifying collinearity among independent variables via the implementation of variance inflation factors (VIFs)) as well as questionnaire-based statistics and potentially principal components analysis (PCA) will be implemented.

Physiological data will be plotted against survey data to create links between RED-S symptoms among various athlete groups (female vs male, able bodied vs disabled, sports groups, age categories, etc.)

Inclusion Criteria:

• International or Canadian elite (National Sport Organization identified) and (Provincial Sport Organization / University varsity identified) Next Generation, or recreational athlete or para-athlete
• Female or male athlete or para-athlete currently and actively training for and racing in an Olympic sports event
• Age >15 years

Exclusion Criteria:

• Under 15 years old
• Pregnant

No data will be shared with researchers outside of the study team.