A Health Media Literacy Intervention Increases Skepticism of Both Inaccurate and Accurate Cancer News Among U.S. Adults.

BACKGROUND: Inaccurate cancer news can have adverse effects on patients and families. One potential way to minimize this is through media literacy training-ideally, training tailored specifically to the evaluation of health-related media coverage. PURPOSE: We test whether an abbreviated health-focused media literacy intervention improves accuracy discernment or sharing discernment for cancer news headlines and also examine how these outcomes compare to the effects of a generic media literacy intervention. METHODS: We employ a survey experiment conducted using a nationally representative sample of Americans (N = 1,200). Respondents were assigned to either a health-focused media literacy intervention, a previously tested generic media literacy intervention, or the control. They were also randomly assigned to rate either perceived accuracy of headlines or sharing intentions. Intervention effects on accurate and inaccurate headline ratings were tested using OLS regressions at the item-response level, with standard errors clustered on the respondent and with headline fixed effects. RESULTS: We find that the health-focused media literacy intervention increased skepticism of both inaccurate (a 5.6% decrease in endorsement, 95% CI [0.1%, 10.7%]) and accurate (a 7.6% decrease, 95% CI [2.4%, 12.8%]) news headlines, and accordingly did not improve discernment between the two. The health-focused media literacy intervention also did not significantly improve sharing discernment. Meanwhile, the generic media literacy intervention had little effect on perceived accuracy outcomes, but did significantly improve sharing discernment. CONCLUSIONS: These results suggest further intervention development and refinement are needed before scaling up similarly targeted health information literacy tools, particularly focusing on building trust in legitimate sources and accurate content.

This study investigated how media literacy training affects people's ability to accurately judge cancer-related news. Specifically, we tested whether health-specific media literacy guidelines could help people better identify accurate versus inaccurate cancer news headlines compared to a set of general media literacy guidelines. Using a survey with 1,200 Americans, participants were divided into three groups: one received health-focused media literacy training, another received general media literacy training, and a third group had no training. Participants were then asked to evaluate or consider sharing a series of accurate and inaccurate news headlines. The study found that the health-focused media literacy training made people more skeptical of both accurate and inaccurate headlines. Meanwhile, the general media literacy guidelines had little effect on perceived accuracy of headlines but did significantly improve the quality of news people said they would share, on average. The findings suggest that more work is needed to improve media literacy programs, especially those focused on health news, to help people trust and recognize accurate information.

Associations between news coverage, social media discussions, and search trends about celebrity deaths, screening, and other colorectal cancer-related events.

OBJECTIVE: Colorectal cancer (CRC) is the third leading cause of cancer death among both men and women in the United States. CRC-related events may increase media coverage and public attention, boosting awareness and prevention. This study examined associations between several types of CRC events (including unplanned celebrity cancer deaths and planned events like national CRC awareness months, celebrity screening behavior, and screening guideline changes) and news coverage, Twitter discussions, and Google search trends about CRC and CRC screening. METHODS: We analyzed data from U.S. national news media outlets, posts scraped from Twitter, and Google Trends on CRC and CRC screening during a three-year period from 2020 to 2022. We used burst detection methods to identify temporal spikes in the volume of news, tweets, and search after each CRC-related event. RESULTS: There is a high level of heterogeneity in the impact of celebrity CRC events. Celebrity CRC deaths were more likely to precede spikes in news and tweets about CRC overall than CRC screening. Celebrity screening preceded spikes in news and tweets about screening but not searches. Awareness months and screening guideline changes did precede spikes in news, tweets, and searches about screening, but these spikes were inconsistent, not simultaneous, and not as large as those events concerning most prominent public figures. CONCLUSIONS: CRC events provide opportunities to increase attention to CRC. Media and public health professionals should actively intervene during CRC events to increase emphasis on CRC screening and evidence-based recommendations.

Using narratives to correct politically charged health misinformation and address affective belief echoes.

BACKGROUND: In May 2020, news outlets reported misinformation about the Centers for Disease Control (CDC) related to COVID-19. Correcting misinformation about outbreaks and politics is particularly challenging. Affective belief echoes continue to influence audiences even after successful correction. Narrative and emotional flow scholarship suggest that a narrative corrective with a positive ending could reduce belief echoes. Therefore, this study investigated the efficacy of a narrative corrective with a relief ending for correcting misinformation about the CDC. METHODS: Between 29 May and 4 June 2020, we tested the effectiveness of a narrative to correct this misinformation. Participants in the United States (N = 469) were enrolled via Qualtrics panels in an online message experiment and randomized to receive a narrative corrective, a didactic corrective or no corrective. RESULTS: The narrative corrective resulted in lower endorsement of the misinformation compared with the control and the didactic corrective. The narrative corrective had a positive indirect effect on perceived CDC competence and mask wearing intentions for politically moderate and conservative participants via relief. CONCLUSIONS: Public health institutions, such as the CDC, should consider utilizing narrative messaging with positive emotion endings to correct misinformation. Narratives better address affective belief echoes, particularly for counter-attitudinal audiences.

Framing COVID-19 Preprint Research as Uncertain: A Mixed-Method Study of Public Reactions.

During the COVID-19 pandemic, journalists were encouraged to convey uncertainty surrounding preliminary scientific evidence, including mentioning when research is unpublished or unverified by peer review. To understand how public audiences interpret this information, we conducted a mixed method study with U.S. adults. Participants read a news article about preprint COVID-19 vaccine research in early April 2021, just as the vaccine was becoming widely available to the U.S. public. We modified the article to test two ways of conveying uncertainty (hedging of scientific claims and mention of preprint status) in a 2 × 2 between-participants factorial design. To complement this, we collected open-ended data to assess participants' understanding of the concept of a scientific preprint. In all, participants who read hedged (vs. unhedged) versions of the article reported less favorable vaccine attitudes and intentions and found the scientists and news reporting less trustworthy. These effects were moderated by participants' epistemic beliefs and their preference for information about scientific uncertainty. However, there was no impact of describing the study as a preprint, and participants' qualitative responses indicated a limited understanding of the concept. We discuss implications of these findings for communicating initial scientific evidence to the public and we outline important next steps for research and theory-building.

Political Party Collective Norms, Perceived Norms, and Mask Wearing Behavior: A Test of the Theory of Normative Social Behavior.

The theory of normative social behavior (TNSB) postulates that people are influenced by others' behaviors, which they observe from messages and experience. In addition to focusing on perceived (i.e., descriptive and injunctive) norms, the TNSB was expanded to include collective norms, which represent what people actually do. Testing this expanded theoretical model, the current study examined whether two types of collective norms - collective political norms and collective regional norms - interacted with descriptive norms to influence pandemic mask wearing behavior expectations among U.S. adults (N = 444). The interaction was statistically significant for collective political norms (ß = -.74, p = .009) but not collective regional norms (ß = -.16, p = .85). Specifically, descriptive norms were related to increased mask wearing expectation for all values of political party collective norms, but the effects were stronger when political party collective norms were low (i.e., low mask wearing behavior was normative). The findings support the inclusion of collective norms in the TNSB, clarify the relationships among different types of norms, and provide insights for norms-based interventions.

Global prevalence and content of information about alcohol use as a cancer risk factor on Twitter.

OBJECTIVES: Alcohol use is a major risk factor for several forms of cancer, though many people have limited knowledge of this link. Public health communicators and cancer advocates desire to increase awareness of this link with the long-term goal of reducing cancer burden. The current study is the first to examine the prevalence and content of information about alcohol use as a cancer risk on social media internationally. METHODS: We used a three-phase process (hashtag search, dictionary-based auto-identification of content, and human coding of content) to identify and evaluate information from Twitter posts between January 2019 and December 2021. RESULTS: Our hashtag search retrieved a large set of cancer-related tweets (N = 1,122,397). The automatic search process using an alcohol dictionary identified a small number of messages about cancer that also mentioned alcohol (n = 9061, 0.8%), a number that got small after adjusting for human coded estimates of the dictionary precision (n = 5927, 0.5%). When cancer-related messages also mentioned alcohol, 82% (n = 1003 of 1225 examined through human coding) indicated alcohol use as a risk factor. Coding found rare instances of problematic information (e.g., promotion of alcohol, misinformation) in messages about alcohol use and cancer. CONCLUSIONS: Few social media messages about cancer types that can be linked to alcohol mention alcohol as a cancer risk factor. If public health communicators and cancer advocates want to increase knowledge and understanding of alcohol use as a cancer risk factor, efforts will need to be made on social media and through other communication platforms to increase exposure to this information over time.

Early cephalopod evolution clarified through Bayesian phylogenetic inference.

BACKGROUND: Despite the excellent fossil record of cephalopods, their early evolution is poorly understood. Different, partly incompatible phylogenetic hypotheses have been proposed in the past, which reflected individual author's opinions on the importance of certain characters but were not based on thorough cladistic analyses. At the same time, methods of phylogenetic inference have undergone substantial improvements. For fossil datasets, which typically only include morphological data, Bayesian inference and in particular the introduction of the fossilized birth-death model have opened new possibilities. Nevertheless, many tree topologies recovered from these new methods reflect large uncertainties, which have led to discussions on how to best summarize the information contained in the posterior set of trees. RESULTS: We present a large, newly compiled morphological character matrix of Cambrian and Ordovician cephalopods to conduct a comprehensive phylogenetic analysis and resolve existing controversies. Our results recover three major monophyletic groups, which correspond to the previously recognized Endoceratoidea, Multiceratoidea, and Orthoceratoidea, though comprising slightly different taxa. In addition, many Cambrian and Early Ordovician representatives of the Ellesmerocerida and Plectronocerida were recovered near the root. The Ellesmerocerida is para- and polyphyletic, with some of its members recovered among the Multiceratoidea and early Endoceratoidea. These relationships are robust against modifications of the dataset. While our trees initially seem to reflect large uncertainties, these are mainly a consequence of the way clade support is measured. We show that clade posterior probabilities and tree similarity metrics often underestimate congruence between trees, especially if wildcard taxa are involved. CONCLUSIONS: Our results provide important insights into the earliest evolution of cephalopods and clarify evolutionary pathways. We provide a classification scheme that is based on a robust phylogenetic analysis. Moreover, we provide some general insights on the application of Bayesian phylogenetic inference on morphological datasets. We support earlier findings that quartet similarity metrics should be preferred over the Robinson-Foulds distance when higher-level phylogenetic relationships are of interest and propose that using a posteriori pruned maximum clade credibility trees help in assessing support for phylogenetic relationships among a set of relevant taxa, because they provide clade support values that better reflect the phylogenetic signal.

For Flux Sake: Isotopic Tracer Methods of Monitoring Human Carbohydrate Metabolism During Exercise.

Isotopic tracers can reveal insights into the temporal nature of metabolism and track the fate of ingested substrates. A common use of tracers is to assess aspects of human carbohydrate metabolism during exercise under various established models. The dilution model is used alongside intravenous infusion of tracers to assess carbohydrate appearance and disappearance rates in the circulation, which can be further delineated into exogenous and endogenous sources. The incorporation model can be used to estimate exogenous carbohydrate oxidation rates. Combining methods can provide insight into key factors regulating health and performance, such as muscle and liver glycogen utilization, and the underlying regulation of blood glucose homeostasis before, during, and after exercise. Obtaining accurate, quantifiable data from tracers, however, requires careful consideration of key methodological principles. These include appropriate standardization of pretrial diet, specific tracer choice, whether a background trial is necessary to correct expired breath CO2 enrichments, and if so, what the appropriate background trial should consist of. Researchers must also consider the intensity and pattern of exercise, and the type, amount, and frequency of feeding (if any). The rationale for these considerations is discussed, along with an experimental design checklist and equation list which aims to assist researchers in performing high-quality research on carbohydrate metabolism during exercise using isotopic tracer methods.

Nutrition and indoor cycling: a cross-sectional analysis of carbohydrate intake for online racing and training.

Cycling is a sport characterised by high training load, and adequate nutrition is essential for training and race performance. With the increased popularity of indoor trainers, cyclists have a unique opportunity to practice and implement key nutritional strategies. This study aimed to assess carbohydrate (CHO) intake of cyclists training or racing in this unique scenario for optimising exercise nutrition. A mixed-methods approach consisting of a multiple-pass self-report food recall and questionnaire was used to determine total CHO intake pre, during and post-training or racing using a stationary trainer and compared with current guidelines for endurance exercise. Sub-analyses were also made for higher ability cyclists (>4 W/kg functional threshold power), races v. non-races and 'key' training sessions. Mean CHO intake pre and post-ride was 0·7 (sd 0·6) and 1·0 (sd 0·8) g kg/BM and 39·3 (sd 27·5) g/h during training. CHO intake was not different for races (pre/during/post, P = 0·31, 0·23, 0·18, respectively), 'key sessions' (P = 0·26, 0·89, 0·98) or higher ability cyclists (P = 0·26, 0·76, 0·45). The total proportion of cyclists who failed to meet CHO recommendations was higher than those who met guidelines (pre = 79 %, during = 86 %, post = 89 %). Cyclists training or racing indoors do not meet current CHO recommendations for cycling performance. Due to the short and frequently high-intensity nature of some sessions, opportunity for during exercise feeding may be limited or unnecessary.

Missing the Bigger Picture: The Need for More Research on Visual Health Misinformation.

Research shows that health misinformation is widespread online and poses a potentially significant threat to public health. Visual misinformation has been largely overlooked, a notable gap given the unique features and ubiquity of visual content. In this essay, we (a) provide a working definition of visual misinformation, (b) summarize the main categories of visual misinformation, (c) offer examples of the functions visuals can serve within misinformation content, and (d) outline priorities for advancing research on visual misinformation. A systematic approach to studying visual misinformation can improve efforts to mitigate health misinformation and optimize science communication in the current information environment.

Visual Juxtapositions as Exemplars in Messages Promoting Healthy Dietary Behavior.

While health communicators often study strategic health messages, investigations of how visual message elements complement or inhibit persuasive efforts are sparse in the literature. Visual juxtapositions, which refer to one visual presentation featuring two images placed next to each other, are one such visual element. In the context of improving public communication efforts related to promoting healthy dietary choices, we use visual persuasion theory and exemplification theory to test whether different visual juxtapositions influence message recipients' expectations to share message content and reduce their consumption of unhealthy products (i.e., sugary drinks and salty foods). We carried out two studies, each a two-wave, longitudinal randomized experiment, to test for direct effects and assess the potential for indirect or delayed associations of visual persuasion appeals using visual juxtapositions. We consistently observed that a similarity visual juxtaposition evoked higher levels of surprise and expectations to share message content than a comparison juxtaposition or control condition immediately following message exposure; however, visual juxtapositions had no direct effects on unhealthy consumption expectations immediately following exposure or one-week following exposure. Levels of surprise were associated with both intended outcomes in the short-term (increased message sharing expectations) and unintended outcomes in the longer-term (increased consumption expectations). Overall, the study offers insights into the effects and associations of visual juxtapositions on message processing and persuasion outcomes, as well as raises questions about how to apply visual persuasion concepts and improve theorizing related to visual persuasion in health communication contexts.

Information Seeking and Scanning about Colorectal Cancer Screening among Black and White Americans, Ages 45-74: Comparing Information Sources and Screening Behaviors.

Cancer information seeking and scanning predict a variety of preventive health behaviors. However, previous work has rarely gauged seeking and scanning of specific cancer screening information. Moreover, colorectal cancer prevalence and mortality rates are higher among black than white Americans and it remains unclear if these groups differ in their cancer screening information acquisition patterns. We surveyed black and white Americans between 45 and 74 years of age to investigate rates, sources, and correlates of colorectal cancer screening (CRCS) information seeking and scanning. Black and white Americans had similar likelihoods of engaging in information seeking and scanning regarding CRCS. However, black Americans reported using significantly more sources for CRCS information seeking and scanning than did white Americans. Both screening test-specific information seeking and scanning are associated with stool-based tests, but only information seeking is associated with flexible sigmoidoscopy or colonoscopy. We discuss study implications for reaching out to different racial groups to promote colorectal cancer screening behavior.

"I Quit": Testing the Added Value and Sequencing Effects of an Efficacy-focused Message among Cigarette Warning Labels.

Many emotional appeal theorists argue that negative affect and efficacy work together to promote adaptive behavioral responses to a threat, yet most research on cigarette warning label messages has not examined the intersection between negative affect, hope, and efficacy. The current study tests effects of exposure, at different points in a sequence, to an efficacy-focused warning label in the context of threat-focused warning labels. We conducted an online, between- and within-subjects experiment with 398 adult smokers, testing the effects of warning label exposure on negative affect, hope, efficacy beliefs, and intentions to quit. Exposure to the efficacy-focused "Quit" label aroused higher levels of reported hope and lower levels of reported negative affect than threat-focused labels. Negative affect increased with each additional exposure to a threat-focused warning label, regardless of the order in which respondents saw the "Quit" label. Exposure to the "Quit" label (within a larger set of three threat-focused labels) led to greater self-efficacy but did not influence response efficacy or intentions to quit. We conclude that "Quit" messaging on warning labels can inspire both hopeful feelings and efficacy beliefs. Future research should identify the optimal balance between threat-focused and hopeful quit messages.

Advancing Visual Health Communication Research to Improve Infodemic Response.

During public health crises like the ongoing novel coronavirus pandemic, there is a need to amplify and improve critical health communication messages. This need is due to pandemics producing infodemic conditions, meaning the public information environment is oversaturated with information of questionable accuracy and utility. The strategic use of visuals can be leveraged to improve the quality of health communication during public health crises and lessen the unintended effects of infodemic conditions. In this essay, we review previous visual communication theorizing and research that provide insights for effective and efficient use of graphical (e.g., data visualizations) and illustrative (e.g., photos, illustrations, and content features) visuals. We also discuss and advocate for more systematic research on visual misinformation and visual narratives, as there are significant gaps in the literature about how people interpret, act on, and engage with these visual content types. More systematic research about these areas of visual health communication research will improve public communication during future public health crises.

Carbohydrate Hydrogel Products Do Not Improve Performance or Gastrointestinal Distress During Moderate-Intensity Endurance Exercise.

The benefits of ingesting exogenous carbohydrate (CHO) during prolonged exercise performance are well established. A recent food technology innovation has seen sodium alginate and pectin included in solutions of multiple transportable CHO, to encapsulate them at pH levels found in the stomach. Marketing claims include enhanced gastric emptying and delivery of CHO to the muscle with less gastrointestinal distress, leading to better sports performance. Emerging literature around such claims was identified by searching electronic databases; inclusion criteria were randomized controlled trials investigating metabolic and/or exercise performance parameters during endurance exercise >1 hr, with CHO hydrogels versus traditional CHO fluids and/or noncaloric hydrogels. Limitations associated with the heterogeneity of exercise protocols and control comparisons are noted. To date, improvements in exercise performance/capacity have not been clearly demonstrated with ingestion of CHO hydrogels above traditional CHO fluids. Studies utilizing isotopic tracers demonstrate similar rates of exogenous CHO oxidation, and subjective ratings of gastrointestinal distress do not appear to be different. Overall, data do not support any metabolic or performance advantages to exogenous CHO delivery in hydrogel form over traditional CHO preparations; although, one study demonstrates a possible glycogen sparing effect. The authors note that the current literature has largely failed to investigate the conditions under which maximal CHO availability is needed; high-performance athletes undertaking prolonged events at high relative and absolute exercise intensities. Although investigations are needed to better target the testimonials provided about CHO hydrogels, current evidence suggests that they are similar in outcome and a benefit to traditional CHO sources.

Obstacles to skin self-examination: are frontier adults inclined abstainers?

Individuals residing in U.S. frontier counties have limited access to dermatology care and higher melanoma mortality rates. Given these limitations, frontier residents rely disproportionately on skin self-examinations (SSE) for early detection of melanoma, though little is known about their SSE behaviors and barriers to conducting SSEs. The goal of the present study was to identify obstacles to SSE performance via a survey of adults (N = 107) living in a U.S. frontier county. Approximately 43% of participants were classified as inclined abstainers - individuals who intended to perform SSE, but failed to follow through. Compared to those who did follow through, inclined abstainers were more likely to be hindered by twelve barriers, including forgetting, letting other tasks get in the way of SSE, and struggling to identify a good time or routine for SSE performance. The barriers to action for these inclined abstainers are modifiable - for example, not remembering to do it - and well positioned for a behavioral intervention.

An evaluation of a motor vehicle facility campaign with an established statewide donor registry: A test of sustainable, evidence-based intervention strategies.

Increasing organ donor registration enrollment inside motor vehicle facilities (MVF) is a common approach in the United States. From this research, a formula for what works has emerged within the literature including the presence of an interpersonal component, video messages, and point-of-decision materials. These intervention components have demonstrated effectiveness at increasing registrations in relatively new statewide registries; however, their effectiveness in MVFs with a mature registry remains understudied. The current study examined the effectiveness of an online MVF clerk intervention and the other examined the effectiveness of a multi-message, phase MVF intervention aimed at increasing organ donation registrations. The results revealed that MVF clerks garnered increased knowledge and greater comfort in communicating about organ donation with patrons after the intervention. Moreover, the intervention revealed that clerk talk effectiveness was positively associated with organ donation registration among MVF customers. Against expectations, recall of video messages was negatively associated with new registrations. Exposure to the brochure, counter mat, and poster donation messages was not associated with organ donation registration. An emphasis on the strengths and shortcomings of using MVFs as intervention sites for organ donation registration promotion are discussed.

A single day of mixed-macronutrient overfeeding does not elicit compensatory appetite or energy intake responses but exaggerates postprandial lipaemia during the next day in healthy young men.

Discrete episodes of overconsumption may induce a positive energy balance and impair metabolic control. However, the effects of an ecologically relevant, single day of balanced macronutrient overfeeding are unknown. Twelve healthy men (of age 22 (sd 2) years, BMI 26·1 (sd 4·2) kg/m2) completed two 28 h, single-blind experimental trials. In a counterbalanced repeated measures design, participants either consumed their calculated daily energy requirements (energy balance trial (EB): 10 755 (sd 593) kJ) or were overfed by 50 % (overfeed trial (OF): 16 132 (sd 889) kJ) under laboratory supervision. Participants returned to the laboratory the next day, after an overnight fast, to complete a mixed-meal tolerance test (MTT). Appetite was not different between trials during day 1 (P>0·211) or during the MTT in the fasted or postprandial state (P>0·507). Accordingly, plasma acylated ghrelin, total glucagon-like peptide-1 and total peptide YY concentrations did not differ between trials during the MTT (all P>0·335). Ad libitum energy intake, assessed upon completion of the MTT, did not differ between trials (EB 6081 (sd 2260) kJ; OF 6182 (sd 1960) kJ; P=0·781). Plasma glucose and insulin concentrations were not different between trials (P>0·715). Fasted NEFA concentrations were lower in OF compared with EB (P=0·005), and TAG concentrations increased to a greater extent on OF than on EB during the MTT (P=0·009). The absence of compensatory changes in appetite-related variables after 1 d of mixed macronutrient overfeeding highlights the limited physiological response to defend against excess energy intake. This supports the concept that repeated discrete episodes of overconsumption may promote weight gain, while elevations in postprandial lipaemia may increase CVD risk.

Liver and muscle glycogen oxidation and performance with dose variation of glucose-fructose ingestion during prolonged (3 h) exercise.

PURPOSE: This study investigated the effect of small manipulations in carbohydrate (CHO) dose on exogenous and endogenous (liver and muscle) fuel selection during exercise. METHOD: Eleven trained males cycled in a double-blind randomised order on 4 occasions at 60% [Formula: see text] for 3 h, followed by a 30-min time-trial whilst ingesting either 80 g h-1 or 90 g h-1 or 100 g h-1 13C-glucose-13C-fructose [2:1] or placebo. CHO doses met, were marginally lower, or above previously reported intestinal saturation for glucose-fructose (90 g h-1). Indirect calorimetry and stable mass isotope [13C] techniques were utilised to determine fuel use. RESULT: Time-trial performance was 86.5 to 93%, 'likely, probable' improved with 90 g h-1 compared 80 and 100 g h-1. Exogenous CHO oxidation in the final hour was 9.8-10.0% higher with 100 g h-1 compared with 80 and 90 g h-1 (ES = 0.64-0.70, 95% CI 9.6, 1.4 to 17.7 and 8.2, 2.1 to 18.6). However, increasing CHO dose (100 g h-1) increased muscle glycogen use (101.6 ± 16.6 g, ES = 0.60, 16.1, 0.9 to 31.4) and its relative contribution to energy expenditure (5.6 ± 8.4%, ES = 0.72, 5.6, 1.5 to 9.8 g) compared with 90 g h-1. Absolute and relative muscle glycogen oxidation between 80 and 90 g h-1 were similar (ES = 0.23 and 0.38) though a small absolute (85.4 ± 29.3 g, 6.2, - 23.5 to 11.1) and relative (34.9 ± 9.1 g, - 3.5, - 9.6 to 2.6) reduction was seen in 90 g h-1 compared with 100 g h-1. Liver glycogen oxidation was not significantly different between conditions (ES < 0.42). Total fat oxidation during the 3-h ride was similar in CHO conditions (ES < 0.28) but suppressed compared with placebo (ES = 1.05-1.51). CONCLUSION: 'Overdosing' intestinal transport for glucose-fructose appears to increase muscle glycogen reliance and negatively impact subsequent TT performance.