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This article provides a recap of the 10 Questions/10 Experts session at the 2024 American College of Sports Medicine Annual Meeting. Each of the speakers considered the validity of common "myths," while providing evidence-based opinions to support, or, bust, myths addressing the following questions: (1) Would 100 g/hr of carbohydrate be advisable for the Olympic Cycling Road race? (2) Is there an advantage in the marathon of ingesting bicarbonate as a hydrogel product? (3) Can genotyping be used to individualize caffeine supplementation in football? (4) Should low fluid consumers drink more to improve 1,500-m track performance? (5) Do urinary markers of dehydration predict poor basketball performance? (6) Do placebo effects influence 10-km track performance? (7) Should combat athletes make weight using glucagon-like peptide-1 receptor agonists? (8) Would crushed ice ingestion help tennis umpires make better decisions in the heat? (9) Are collagen supplements useful to reduce tendon and ligament injuries in volleyball? and (10) Should female athletes plan their training and diet according to their menstrual cycle? This article describes the content of each of the presentations including the most important outcomes and conclusions drawn by the presenters. [ABSTRACT FROM AUTHOR]

There is little evidence that body size alters exogenous glucose oxidation rates during exercise. This study assessed whether larger people oxidize more exogenous glucose during exercise than smaller people. Fifteen cyclists were allocated into two groups based on body mass (SMALL, <70 kg body mass, n = 9, two females) or (LARGE, >70 kg body mass, n = 6) matched for lactate threshold (SMALL: 2.3 ± 0.4 W/kg, LARGE: 2.3 ± 0.3 W/kg). SMALL completed 120 min of cycling at 95% of lactate threshold1. LARGE completed two trials in a random order, one at 95% of lactate threshold1 (thereby exercising at the same relative intensity [RELATIVE]) and one at an absolute intensity matched to SMALL (ABSOLUTE). In all trials, cyclists ingested 90 g/hr of 13C-enriched glucose. Total exogenous glucose oxidation was (mean ± SD) 33 ± 8 g/hr in SMALL versus 45 ± 13 g/hr in LARGE-RELATIVE (mean difference: 13 g/hr, 95% confidence interval [2, 24] g/hr, p =.03). Large positive correlations were observed for measures of exogenous carbohydrate oxidation versus body size (body mass, height, and body surface area; e.g., body surface area vs. peak exogenous glucose oxidation, r =.85, 95% confidence interval [.51,.95], p <.01). When larger athletes reduced the intensity from RELATIVE to ABSOLUTE, total exogenous glucose oxidation was 39 ± 7 g/hr (p =.43 vs. LARGE-RELATIVE). In conclusion, the capacity for exogenous glucose oxidation is, on average, higher in larger athletes than smaller athletes during exercise. The extent to which this is due to higher absolute exercise intensity requires further research, but body size may be a consideration in tailoring sports nutrition guidelines for carbohydrate intake during exercise. Consuming carbohydrates (especially sugars) during prolonged exercise can delay fatigue and improve performance. As a result, sports nutrition guidelines suggest that athletes should ingest carbohydrates during prolonged exercise to maximize endurance. Recommendations about how much carbohydrate a person needs during exercise are based on a number of factors—an important one is how much carbohydrate the body can actually use as a fuel during that exercise (for example, if our muscles can use 1 gram of carbohydrate per minute of exercise, then ingesting 60 grams of carbohydrate per hour might be recommended). Indeed, previous research does appear to suggest that the amount of carbohydrate that our muscles can use is often limited to approximately 1 gram per minute and, importantly, that seemed to be fairly consistent between different people no matter how large or small they are (so everybody might be recommended to ingest 60 grams of glucose per hour irrespective of their body size). However, to date, no study had directly tested this question by specifically recruiting people of different body sizes and comparing them side-by-side to see how much ingested carbohydrate they could burn during exercise. This is important because, if larger people can use more than smaller people, then this would provide a justification to adjust carbohydrate intake guidelines based on body weight and/or other measures of body size (like height or the size of particular bodily measurements). We carefully recruited male and female cyclists who were classified as either smaller (~67 kg/148 lbs; ~178 cm/5′10″) or larger (~87 kg/192 lbs; ~190 cm/6′3″) body size and asked them to cycle for 2 hours at a moderate intensity (i.e. heart rate ~ bpm) while consuming carbohydrate drinks every 15 minutes in amounts to provide 90 grams of glucose during each hour. The glucose molecules we gave them to drink were labeled with a particular naturally occurring but rare form of the sugar so we could trace where the ingested carbohydrates ended up—for example, with this method we could measure how much of the ingested carbohydrates were used for energy during exercise. By doing this, we revealed for the first time, that larger athletes can oxidize substantially more carbohydrates than smaller athletes during exercise. On average, larger athletes could burn 36% more ingested carbohydrates than smaller athletes. This evidence calls for further investigations into the relationship between body size and metabolism during exercise—which should include looking at different types of carbohydrates and different intensities of exercise. In the meantime, based on what we now know, athletes are likely to gain performance benefits from some degree of tailoring carbohydrate intake based on body size (i.e., bigger athletes may need more). If carbohydrate intake is not adjusted according to size, then smaller athletes may be ingesting more carbohydrates than they need (with the excess possibly building up in the intestine and causing discomfort), whereas larger athletes may not be ingesting sufficient carbohydrate to meeting their full capacity to use ingested fuels so fail to achieve their full performance potential. [ABSTRACT FROM AUTHOR]

Carbohydrates constitute one of the key classes of biomacromolecules, yet vibrational spectroscopic studies involving carbohydrates remain scarce as spectra are highly congested and lack significant marker vibrations. Recently, we introduced and characterized a thiocyanate-labeled glucose [Gasse et al., J. Chem. Phys. 158, 145101 (2023)] demonstrating 2D-IR spectroscopy of carbohydrates using vibrational probes. Here, we build on that work and test azide groups as alternative for studies of carbohydrates to expand the available set of local probes. Many common carbohydrates with different azide labeling positions, such as galactose, glucose, or lactose, are readily available due to their application in click chemistry and hence do not require additional complex synthesis strategies. In this work, we have characterized azide-labeled glucose,, galactose, acetylglucosamine and lactose in water using IR and 2D-IR spectroscopy to test their potential for future applications in studies of carbohydrate–protein interactions. Our findings indicate that their absorption profiles and vibrational dynamics are primarily determined by the labeling position on the ring. However, we also observe additional variations between samples with the same labeling position. Furthermore, we demonstrate that their usage remains feasible at biologically relevant concentrations, highlighting their potential to probe more complex biological processes, i.e., enzymatic catalysis. [ABSTRACT FROM AUTHOR]

The pervasive presence of nanoplastics (NPs) in the environment has gained increasing attention due to their accumulation in living organisms. These emerging contaminants inevitably interact with extracellular polymeric substances along respiratory or gastrointestinal tracts, and diverse organic coating on the surface of NPs, known as bio- or eco-corona, is formed. Although its impact on altering the NP properties and potential cell internalization has been extensively examined, studies on its role in NP partitioning in the cell membrane are elusive yet. In this work, molecular dynamics is used to investigate the formation of chitosan (CT) corona centered on a polyvinyl chloride (PVC) nanoparticle and the uptake of the resulting complex onto lipid membranes. Coarse-grained models compatible with the newly developed Martini 3.0 force field are implemented for the two polymers employing the atomistic properties as targets in the parameterization. The reliability of the coarse-grained polymer models is demonstrated by reproducing the structural properties of the PVC melt and of solvated CT strands, as well as by determining the conformation adopted by the latter at the NP surface. Results show that the spontaneous binding of CT chains of high and intermediate protonation degrees led to the formation of soft and hard corona that modulates the interaction of PVC core with model membranes. The structural changes of the corona adsorbed at the lipid–water interface enable a subsequent transfer of the NP to the center of the saturated lipid membranes and a complete or partial transition to a snorkel conformation depending on the hydrophilic/hydrophobic balance in the CT–PVC complex. Overall, the computational investigation of the coarse-grained model system provides implications for understanding how the eco-corona development influences the uptake and implicit toxicology of NPs. [ABSTRACT FROM AUTHOR]

Rapid microwave-assisted deep eutectic solvents (DES) pretreatment proves to be an efficient strategy for enhancing the valorization of carbohydrates in corn straw (CR). A remarkable improvement in enzymatic hydrolysis yield (26.3–84.1%) was achieved through pretreating CR with a choline chloride/lactic acid DES at 110 °C for 20 min via microwave-assisted heating. In the subsequent dark fermentation stage, a maximum cumulative hydrogen yield of 96.4 mL/g total solids was attained. The improved conversion efficiency was attributed to the efficient dissociation of non-cellulose components, with lignin and hemicellulose removal rates of 56.5% and 63.6%, respectively. In short, the microwave-facilitated DES pretreatment provides valuable insights and practical aids for enhancing the separation and biohydrogen generation from lignocellulosic biomass. [Display omitted] • Microwave-assisted DES pretreatment was proposed for fractionation of corn straw. • Microwave-assisted DES system rapidly destroyed the structure of corn straw. • The highest enzymatic hydrolysis efficiency reached 84.1% under the mild condition. • A maximum biohydrogen yield of 96.4 mL/g total solids was achieved. [ABSTRACT FROM AUTHOR]

Partial methylation of hydroxyl groups plays a crucial role in structural modification, functional optimization, and bioactivity regulation of carbohydrate compounds. Despite its significance, research in this field remains scarce. Furthermore, traditional methylating reagents are frequently associated with toxicity and environmental pollution issues. Herein, we report the application of trimethylsulfonium iodide [(CH3)3S(O)I] as a green and efficient methylating agent for the methylation of carbohydrate substrates. By combining (CH3)3S(O)I with an efficient iron catalytic system, we achieved site selectivity and high yield in the reaction. [ABSTRACT FROM AUTHOR]