Time-Restricted Eating in Community-Dwelling Adults: Correlates of Adherence and Discontinuation in a Cross-Sectional Online Survey Study.

BACKGROUND: Time-restricted eating (TRE), a type of intermittent fasting in which all daily calories are consumed within a window of ≤12 hours, is hypothesized to promote long-term weight management because of its relative simplicity. OBJECTIVE: This study reports correlates of adherence among community-dwelling adults currently or formerly following a TRE dietary strategy. DESIGN: A 25-minute cross-sectional online survey was developed, including questions about TRE perceptions, behaviors, motivators and drivers, and demographics. The survey was administered in February 2021 via Prolific, an online platform for sample recruitment and survey dissemination. PARTICIPANTS: Eligibility criteria included US adult ages 18+ who currently or formerly (past 3 months) followed TRE (ie, consumed all daily calories within a window of ≤12 hours) for a minimum of 1 week. STATISTICAL ANALYSES: χ2 tests and analysis of covariance (ANCOVA; adjusting for sex and age) compared responses between current and former followers. RESULTS: Current followers (n = 296, mean [SD]: 34.2 ± 12.2y) were older than former followers (n = 295, mean [SD]: 31.1 ± 10.9 y) and practiced TRE for longer (median: 395 vs 90 days, P < 0.001). Current followers reported more success with meeting TRE goals (P ≤ 0.015), were less likely to report TRE concerns (P < 0.001), and more likely to report TRE satisfaction (P < 0.001). Four TRE motivators were more important among current (vs former) followers: weight maintenance, health (not weight), improved sleep, and preventing disease (P ≤ 0.017); weight loss was more important among former (vs current) followers (P = 0.003). Among adherence drivers, ability to work from home and the impact of COVID-19 were reported as more helpful for TRE adherence among current compared with former followers (P ≤ 0.028). CONCLUSIONS: TRE motivators and drivers differed between current and former followers; interventions tailored to individuals' preferences and circumstances may benefit TRE adherence.

Physical Activity, Stress, and Physically Active Stress Management Behaviors Among University Students With Overweight/Obesity.

Student physical activity is associated with lower stress. Research gaps remain regarding the types of stress management behaviors students use and how these behaviors are associated with students' activity levels. This study examined associations between physical activity and stress management behaviors among students (18-35 years). Students with overweight/obesity (n = 405) attending universities in 2 urban locations enrolled in a randomized controlled trial to promote healthy weight and completed the following baseline measurements: perceived stress, stress management behaviors, accelerometer-measured physical activity, and demographic characteristics. Perceived stress did not differ by physical activity status or race. A greater proportion of students meeting moderate-to-vigorous physical activity guidelines used physically active stress management behaviors compared to those not meeting guidelines (74% vs 56%; P = .006), and students using physically active stress management had lower stress scores (13.1 vs 15.5; P = .003). Among Black and White students only (n = 306), a greater proportion of White students used physically active stress management behaviors compared to Black students (77% vs 62%, P = .013). Results indicate differences in stress management behaviors by student activity level and race. During times of high stress, colleges/universities might support students by promoting stress management and physical activity in tandem, and tailoring messages to student activity levels and demographic characteristics.

Personalized versus generic digital weight loss interventions delivered on university campuses: a 6-month cost-benefit analysis.

Cost-effectiveness analyses of weight loss programs for university students can inform administrator decision-making. This study quantifies and compares the costs and cost-effectiveness of implementing two digitally-delivered weight loss interventions designed for university populations. Healthy Body Healthy U (HBHU) was a randomized controlled trial comparing TAILORED (personalized) versus TARGETED (generic) weight loss interventions adapted specifically for young adults to a CONTROL intervention. Participants (N = 459; 23.3 ± 4.4 years; mean BMI 31.2 ± 4.4 kg/m2) were recruited from two universities. Implementation costs were examined from a payer (i.e., university) perspective, comparing both the average cost effectiveness ratio (ACER) and the incremental cost effectiveness ratio (ICER) of the two interventions. Cost-effectiveness measures were calculated for changes in body weight, abdominal circumference, HDL cholesterol, systolic and diastolic blood pressure, and HbA1c. The overall 6-month implementation costs were $105.66 per person for the TAILORED intervention and $91.44 per person for the TARGETED intervention. The ACER for weight change was $107.82 for the TAILORED and $179.29 for the TARGETED interventions. The ICER comparing TAILORED with TARGETED for change in body weight was $5.05, and was even lower ($2.28) when including only those with overweight and not obesity. The ICERs for change in abdominal circumference, HDL cholesterol, systolic and diastolic blood pressure, and HbA1c were $3.49, $59.37, $1.57, $2.64, and $47.49, respectively. The TAILORED intervention was generally more cost-effective compared with the TARGETED intervention, particularly among those with overweight. Young adults with obesity may require more resource-intensive precision-based approaches.

Knowledge about the cost-effectiveness of weight loss programs for university students is needed to inform administrator decision-making regarding whether to provide such programming. This study examined the cost-effectiveness of two digitally-delivered weight loss interventions (i.e., TAILORED and TARGETED) designed for university students. The TAILORED intervention included information tailored to the individual, while the TARGETED intervention included only generic weight loss information. At 6 months, the average cost per kilogram of weight loss was $107.82 for TAILORED participants and $179.29 for TARGETED participants. The TAILORED intervention was generally more cost-effective compared with the TARGETED intervention.

Sleep duration and chronotype of pregnant women in the United States: An online cross-sectional survey study.

Sleep is an important behavior, and during pregnancy plays a critical role in promoting the health of both woman and child. Therefore, identifying and addressing sleep parameters during pregnancy, and associated disparities in maternal-child health outcomes, is a public health priority. This studied aimed to examine chronotype and sleep duration in pregnant women by sociodemographic factors. An online survey was distributed to currently pregnant women living in the greater Washington, DC, area of the United States from March to May of 2022. The survey included the ultra-short version of the Munich Chronotype Questionnaire (µMCTQ), which was used to calculate the mid-point of sleep time (MST; a measure of chronotype) and sleep duration, as well as demographic questions. Linear regression was used to assess differences in sleep outcomes by demographic factors. A sample of n = 142 currently pregnant women were eligible for analysis. In covariate adjusted models, sleep duration was longer among respondents ages 25-34 (09:52) compared with younger respondents ages 18-24 (08:59; p = 0.014), and shorter for those with a household income ≥ 100,000 United States dollars (USD) (07:42) compared with those with a household income < 50,000 USD (08:59; p = 0.001). No differences in mean mid-point of sleep were identified across demographic factors. Differences in sleep duration by age and household income were found among currently pregnant women. Future studies should investigate sleep parameters and other factors that may influence maternal-child health disparities.

Associations Between College/University Physical Activity Requirements and Student Physical Activity.

Background: Most U.S. college students do not meet physical activity guidelines. Physical activity requirements (PAR) are a proposed solution for increasing undergraduate physical activity. Purpose: To determine whether college/university PAR are associated with undergraduates' self-reported physical activity. Methods: Undergraduate students (N = 383,632) attending colleges and universities taking part in the American College Health Association-National College Health Assessment II survey (2015-2019) self-reported physical activity and demographics. Using websites and course catalogs, researchers coded schools to indicate binary PAR status. Bayesian Hierarchical Logistic Regression was used to determine the percentage of students meeting physical activity guidelines; interactions between PAR status and student characteristics (sex, BMI) were examined. Results: PAR status was positively associated with percent of students meeting physical activity guidelines (PAR: 43.3%, without: 40.5%; difference score 95% Highest Density Interval [HDI; 1.0, 4.5]). A greater percentage of students attending schools with PAR, versus without, met physical activity guidelines across all categories of sex and weight. However, the positive relationship between PAR status and physical activity was stronger among male students (PAR: 46.7%, without: 43.2%; 95% HDI [1.6, 5.4]) compared to female students (PAR: 39.9%, without: 37.9%; 95% HCI [0.2, 3.8]), and among students with underweight (PAR: 39.2%, without: 35.5%; 95% HDI [1.2, 6.3]) or obesity (PAR: 37.1%, without: 33.7%; 95% HDI [1.4, 5.3]) compared to normal weight (PAR: 49.3%, without: 47.4%; 95% HDI [0.1, 3.7]) or overweight (PAR: 47.5%, without: 45.5%; 95% HDI [0.1, 4.0]). Conclusions: PAR are associated with meeting physical activity guidelines, particularly among college/university students with underweight or obesity.

Application of McGuire's Model to Weight Management Messages: Measuring Persuasion of Facebook Posts in the Healthy Body, Healthy U Trial for Young Adults Attending University in the United States.

Digital communication is a common intervention channel for weight loss, yet little is known about the types of messages that are most effective. Using McGuire's Model of Communication and Persuasion as a framework, this study investigates the persuasiveness of Facebook messages posted as part of the weight loss intervention in the Healthy Body Healthy U (HBHU) study to determine what message characteristics prompt higher engagement on Facebook, and whether certain messages are more appealing to certain demographics. The first four weeks of HBHU Facebook posts (n = 32) were coded according to McGuire's Input Communication Factors. Facebook engagement scores [(Total Engaged Users/Total Reach) × 100] were calculated for each post to determine effectiveness. The most effective posts were diet-related discussions or interactive polls. Participants who engaged with the highest and lowest effect posts were in their mid-twenties and tended to be female. Those engaged with the highest effect posts had an average BMI of 32.34 kg/m2, while those engaged with the lowest effect posts had an average BMI of 31.31 kg/m2. The least effective posts were didactic lessons (i.e., diet- or reminder-based), or video-based informational posts (edutainment). Future interventions should balance didactic content and interactive engagement to achieve persuasive messaging.

Women's Satisfaction With Telehealth Services During The COVID-19 Pandemic: Cross-sectional Survey Study.

BACKGROUND: Since March 2020, the need to reduce patients' exposure to COVID-19 has resulted in a large-scale pivot to telehealth service delivery. Although studies report that pregnant women have been generally satisfied with their prenatal telehealth experiences during the pandemic, less is known about telehealth satisfaction among postpartum women. OBJECTIVE: This study examined telehealth satisfaction among both pregnant and recently pregnant women during the COVID-19 pandemic, to determine whether demographic factors (ie, race, age, marital status, education level, household income, and employment status) are associated with telehealth satisfaction in this population. METHODS: A web-based cross-sectional survey designed to capture data on health-related behaviors and health care experiences of pregnant and recently pregnant women in the United States was disseminated in Spring 2022. Eligible participants were at least 18 years old, identified as a woman, and were currently pregnant or had been pregnant in the last 3 years. RESULTS: In the final analytic sample of N=403, the mean telehealth satisfaction score was 3.97 (SD 0.66; score range 1-5). In adjusted linear regression models, being aged 35-44 years (vs 18-24 years), having an annual income of ≥ US $100,000 (vs < US $50,000), and being recently (vs currently) pregnant were associated with greater telehealth satisfaction (P≤.049). CONCLUSIONS: Although perinatal women are generally satisfied with telehealth, disparities exist. Specifically, being aged 18-24 years, having an annual income of < US $50,000, and being currently pregnant were associated with lower telehealth satisfaction. It is critical that public health policies or programs consider these factors, especially if the expanded use of telehealth is to persist beyond the pandemic.

A qualitative exploration of facilitators and barriers of adherence to time-restricted eating.

Time-restricted eating (TRE), a dietary strategy that involves limiting daily energy intake to a window of ≤12 h is appealing for weight management and metabolic health due to its relative simplicity and the ability to consume ad libitum diet during eating windows. Despite the potential utility of TRE for improving health and reducing disease, the feasibility of adherence depends upon a variety of multilevel factors which are largely unexplored. The primary aim of our study was to explore facilitators and barriers of adherence to TRE among community-dwelling individuals. Semi-structured qualitative interviews were conducted among 24 individuals (50% male; M age: 34, range: 18-57; 58% overweight/obese) who currently or formerly practiced TRE. Thematic analysis identified facilitators of and barriers to TRE adherence at multiple levels of influence (i.e., biological, behavioral, psychosocial, environmental). Key facilitators of adherence included improvements in physical health and energy levels, alignment with other aspects of diet, exercise and sleep patterns, self-monitoring and positive psychological impacts, social support, and busy or regular schedules. Key barriers included negative physical health effects, feelings of hunger and sluggishness, difficulty in skipping valued baseline eating routines or inadequate diet quality during the eating window, misalignment of TRE with 24-h activity behaviors, difficulties with self-monitoring, the need to mitigate negative feelings, social situations that discourage TRE, and irregular or idle schedules. Results illustrate that key drivers of adherence differ across individuals and their unique settings and that multiple drivers of behavior should be considered in the successful implementation of TRE. Findings may inform interventions seeking to tailor TRE schedules to fit individuals' diverse behavioral patterns and preferences, thereby optimizing adherence.

Dietary Behaviors, Physical Activity, and Reported Role Models Among Emerging and Young Adults With Overweight and Obesity.

This article characterizes role models identified by emerging/young adults for healthy eating and physical activity (PA), explores variations in reported role models by age, sex and race/ethnicity, and examines dietary/physical activity behaviors in relation to role models. Emerging/young adults (n=397) enrolled in a randomized controlled weight management trial completed assessments at baseline: self-reported role models for healthy eating and PA, Healthy Eating Index, device-measured PA, and demographics. Participants were 78% female, 50% non-White, with mean age 23.3 years, mean BMI 31.1 kg/m2. For both healthy eating and PA, the most frequently reported role model was friend (diet: 35%; PA: 39%). Parent was reported second most frequently for healthy eating (21%) and third most frequently for PA (11%). Role models for healthy eating, but not PA, differed by race/ethnicity. Role models did not differ by age or sex. Results may inform future interventions to promote healthy behaviors in emerging adults.

Implementation of nutrition and physical activity-related policies and practices on college campuses participating in the Healthier Campus initiative.

Objective: To evaluate implementation of nutrition/physical activity-related policies/practices at colleges participating in a healthy campus initiative and campus health leaders' perceptions of policies/practices' support for student health and ease of/barriers to implementation. Participants: Health leaders at colleges participating in the Healthier Campus Initiative (HCI), with completed or ongoing three-year HCI commitments. Methods: Surveys asked which of 41 guidelines were implemented and perceptions around support for student health and ease of/barriers to implementation. Qualitative interviews explored similar domains. Results: Campuses with completed HCI commitments (n = 17) averaged 27.6 guidelines implemented, versus 21.1 on campuses with commitments ongoing (n = 13; p = 0.003). Perceived support for student health and implementation ease varied by guideline. Common implementation barriers included financial costs and time. Interviews largely reinforced these findings. Conclusions: Completion of a campus environmental change initiative may be associated with more health-supporting practices. Campuses may benefit from implementing coordinated policy/practice changes supporting healthy eating and physical activity.

Prevalence of Physical Activity Requirements Among US Colleges/Universities Participating in the American College Health Association-National College Health Assessment II.

Physical activity requirements (PAR; ie, courses required for graduation) have been proposed as a policy solution for increasing undergraduate physical activity. This study aimed to report prevalence of PAR among US colleges/universities participating in the American College Health Association-National College Health Assessment (ACHA-NCHA) and to understand whether these requirements were associated with campus characteristics. Data from the American College Health Association-National College Health Assessment II serial cross-sectional survey (2015-2019) were merged with researcher coded variables (2019): binary PAR status, nature of PAR (activity-based, conceptual, or combination), and number of courses required to fulfill the PAR. Logistic regression determined whether campus characteristics were associated with PAR in 2019. Nonparametric tests examined differences in nature and number of PAR courses. Of 379 schools, 59 (15.6%) had PAR, with 36 (61.0%) having activity-based PAR and 23 (39.0%) having a combination. Compared to public and four-year schools, private (OR=3.47 [1.77, 6.80]) and two-year schools (OR=6.55 [2.21, 19.45]) had significantly increased odds of having PAR. Private schools required significantly more PAR courses compared to public schools (2.42 vs. 1.73, P=.005). PAR were less prevalent in this sample than reported historically, indicating need for campus leadership attention to this issue. Research is needed to understand what barriers exist to implementing and maintaining PAR on college/university campuses, particularly among public and four-year schools. Understanding health promotion practices among ACHA member schools, which have made leadership commitments to promote student health, can provide greater knowledge of PAR barriers and best practices in schools across the United States and globally.

What moves young people? Applying the risk perception attitude framework to physical activity behavior and cardiometabolic risk.

Cardiometabolic disease risk factors, including metabolic syndrome and physical inactivity, are prevalent among young adults. However, few young adults are aware of their risk status. The risk perception attitude (RPA) framework was used to categorize participants (n = 456) enrolled in a three-arm randomized controlled weight management trial by their baseline values of cardiometabolic risk perceptions and physical activity self-efficacy. Trial recruitment occurred at two universities from 2015 to 2018 and participants were randomly assigned to one of three weight management interventions: Tailored, Targeted, Control. Cross-sectional and longitudinal analyses were conducted to examine associations between RPA category (i.e., Responsive, Indifferent, Avoidant, Proactive) and physical activity behavior. At baseline, the Responsive group had the highest amount of physical activity (mean [95% CI]: 379.2 [332.6 to 425.8] min/week), the Indifferent group had the lowest (296.7 [261.98 to 331.32] min/week), and the Avoidant/Proactive groups showed intermediate values. Over 6 months, there was a significant interaction between RPA group and intervention arm on change in physical activity adjusted for age, sex, race/ethnicity, baseline body mass index, and baseline moderate-to-vigorous physical activity (p = .017). Among Tailored intervention participants only, the Proactive participants were the only group to have an increase in physical activity (19.97 min/week) and the Indifferent participants had the most significant decrease in physical activity (127.62 min/week). Results suggest the importance of early screening for young adults to help raise awareness of cardiometabolic risk and ultimately support them in health promotion efforts.

Associations between college/university campus characteristics and student body mass index.

BACKGROUND: Campus environments are associated with undergraduate weight. However, few studies have examined campus type and geographic location in relation to student weight. This article aimed to identify college/university students with elevated BMIs by campus type and region. METHODS: Linear mixed effects regression models were fit to data from the American College Health Association-National College Health Assessment II. Analyses tested associations between campus type/region and student self-reported BMI. RESULTS: The sample included 404,987 students from 445 schools with mean BMI 24.9 ± 5.8. Across all school types/regions, BMI confidence intervals included overweight values. Two-year and public school students had higher BMIs compared to four-year and private school students, respectively. Students in the Midwest had higher BMIs compared to students in the Northeast. In the South only, Minority Serving Institution (MSI) students had higher BMIs compared to non-MSI students. CONCLUSION: Healthy weight maintenance programs should be made available to undergraduate students.

Feasibility of a Digital Intervention to Promote Healthy Weight Management among Postpartum African American/Black Women.

The study aim was to implement and evaluate the feasibility of a culturally informed ("BeFAB") app for African American/Black women to address postpartum weight. Women (n = 136; mean age = 27.8 ± 5.4; mean BMI = 32.5 ± 4.3) were recruited from postpartum units, and randomly assigned to receive BeFAB (n = 65) or usual care (n = 71) for 12 weeks. App content included didactic lessons delivered via a virtual coach, app-based messages, goal setting and tracking, and edutainment videos. Feasibility outcomes included recruitment, retention and engagement, and self-reported acceptability. Behavioral (i.e., diet, physical activity), psychosocial (i.e., stress, coping, support, self-efficacy) and weight outcomes were also examined. Recruitment goals were met, but attrition was high, with 56% retention at 12 weeks. Approximately half of participants accessed the app and set a goal ≥one time, but <10% reported achieving a nutrition or activity goal. Among study completers, ≥60% found the app content at least somewhat helpful. Within-group changes for BeFAB among completers were found for increased moderate-to-vigorous physical activity and decreased fruit/vegetable intake and weight. Findings indicate initial feasibility of recruiting postpartum women to participate in a digital healthy body weight program but limited use, reflecting low acceptability and challenges in engagement and retention. Future research is needed on strategies to engage and retain participants in postpartum interventions.

Perspective: Time-Restricted Eating Compared with Caloric Restriction: Potential Facilitators and Barriers of Long-Term Weight Loss Maintenance.

A growing body of literature examines the potential benefits of a time-based diet strategy referred to as time-restricted eating (TRE). TRE, a type of intermittent fasting, restricts the time of eating to a window of 4-12 h/d but allows ad libitum intake during eating windows. Although TRE diets do not overtly attempt to reduce energy intake, preliminary evidence from small studies suggests that TRE can lead to concomitant reduction in total energy, improvements in metabolic health, and weight loss. Unique features of the TRE diet strategy may facilitate adherence and long-term weight loss maintenance. In this Perspective, we explore the potential multilevel (i.e., biological, behavioral, psychosocial, environmental) facilitators and barriers of TRE for long-term weight loss maintenance in comparison with the more commonly used diet strategy, caloric restriction (CR). Compared with CR, TRE may facilitate weight loss maintenance by counteracting physiological adaptations to weight loss (biological), allowing for usual dietary preferences to be maintained (behavioral), preserving executive functioning (psychosocial), and enabling individuals to withstand situational pressures to overeat (environmental). However, TRE may also pose unique barriers to weight loss maintenance, particularly for individuals with poor baseline diet quality, internal or social pressures to eat outside selected windows (e.g., grazers), and competing demands that interfere with the scheduling of eating. Future studies of TRE in free-living individuals should consider the multiple levels of influence impacting long-term adherence and weight loss maintenance. Ultimately, TRE could be one strategy in a toolkit of tailored diet strategies to support metabolic health and weight loss maintenance.

College campuses' influence on student weight and related behaviours: A review of observational and intervention research.

Research indicates that most college students are not meeting dietary and physical activity guidelines, and the average student gains an estimated 1.6-3.0 kg during 4 years of study. College administrations are well-positioned to influence student weight-related health behaviours by ensuring that campus environments/policies promote health. However, to date, campus health interventions have largely addressed individual and interpersonal factors rather than environmental/policy-level changes. Using an ecological perspective, this narrative review synthesizes the literature on campus environmental/policy-level factors (e.g., food availability, physical activity requirements) associated with student diet, physical activity and weight, as well as campus interventions to address these factors. Web of Science and PubMed databases were searched between December 2018 and November 2019. Results indicate that campus food environments may contribute to overconsumption and weight gain, and the number of campuses requiring students to participate in physical activity courses is in decline. Eight examples of environmental/policy-level campus interventions are presented: nutrition labels in dining halls, campus-wide healthy choice marketing campaigns, restricted payment methods for à la cart dining, trayless dining, health-themed residence halls, peer health education programmes, active classroom spaces and physical activity course requirements. Implications for research and health promotion programmes/policies in the field of college health are discussed.

Addressing Challenges with the Categorization of Foods Processed at Home: A Pilot Methodology to Inform Consumer-Facing Guidance.

The objective of this study was to inform consumer-facing dietary guidance by (1) adapting the current University of North Carolina at Chapel Hill (UNC) food processing framework to include a home processing (HP) component and (2) pilot testing the adapted version using a nationally representative sample of foods consumed in the U.S. The UNC framework was adapted to include guidelines for categorizing home-prepared (HP) foods. The original UNC and adapted HP frameworks were used to code dietary recalls from a random sample of National Health and Nutrition Examination Survey (2015-2016 cycle) participants (n = 100; ages 2-80 years). Percent changes between the UNC and HP adapted frameworks for each processing category were calculated using Microsoft Excel, version 16.23. Participants were 56% female, 35% non-Hispanic white (mean age = 31.3 ± 23.8). There were 1,376 foods with 651 unique foods reported. Using the HP compared to the UNC framework, unprocessed/minimally processed foods declined by 11.7% (UNC: 31.0% vs. HP: 27.4%); basic processed foods increased by 116.8% (UNC: 8.2% vs. HP: 17.8%); moderately processed foods increased by 16.3% (UNC: 14.2% vs. HP: 16.6%); and highly processed foods decreased by 17.8% (UNC: 46.5% vs. HP: 38.2%). Home-prepared foods should be considered as distinct from industrially produced foods when coding dietary data by processing category. This has implications for consumer-facing dietary guidance that incorporates processing level as an indicator of diet quality.

A review of the ketogenic diet for endurance athletes: performance enhancer or placebo effect?

BACKGROUND: The ketogenic diet has become popular among endurance athletes as a performance enhancer. This paper systematically reviews the evidence regarding the effect of the endurance athlete's ketogenic diet (EAKD) on maximal oxygen consumption (VO2 max) and secondary performance outcomes. METHODS: PubMed and Web of Science searches were conducted through November 2019. Inclusion criteria were documentation of EAKD (< 50 g daily carbohydrate consumed by endurance athletes), ketosis achieved (measured via serum biomarker), VO2 max and/or secondary outcomes, English language, and peer reviewed-publication status. Articles were excluded if they were not a primary source or hypotheses were not tested with endurance athletes (i.e., individuals that compete at submaximal intensity for extended time periods). Study design, diet composition, adherence assessment, serum biomarkers, training protocols, and VO2 max/secondary outcomes were extracted and summarized. RESULTS: Searches identified seven articles reporting on VO2 max and/or secondary outcomes; these comprised six intervention trials and one case study. VO2 max outcomes (n = 5 trials, n = 1 case study) were mixed. Two of five trials reported significant increases in VO2 max across all diets; while three trials and one case study reported no significant VO2 max findings. Secondary outcomes (n = 5 trials, n = 1 case study) were Time to Exhaustion (TTE; n = 3 articles), Race Time (n = 3 articles), Rating of Perceived Exertion (RPE; n = 3 articles), and Peak Power (n = 2 articles). Of these, significant findings for EAKD athletes included decreased TTE (n = 1 article), higher RPE (n = 1 article), and increased Peak Power (n = 1 article). CONCLUSION: Limited and heterogeneous findings prohibit definitive conclusions regarding efficacy of the EAKD for performance benefit. When compared to a high carbohydrate diet, there are mixed findings for the effect of EAKD consumption on VO2 max and other performance outcomes. More randomized trials are needed to better understand the potentially nuanced effects of EAKD consumption on endurance performance. Researchers may also consider exploring the impact of genetics, recovery, sport type, and sex in moderating the influence of EAKD consumption on performance outcomes.