The effects of carbohydrate (CHO) intake on substrate metabolism, exercise capacity, and exercise performance have been studied for >100 y. From a metabolic perspective, the ergogenic effect of CHO intake is likely mediated by liver (and potentially muscle) glycogen sparing, maintenance of plasma glucose concentrations, and whole-body CHO oxidation rates, such that the required exercise intensity can be sustained for a longer duration thereby delaying fatigue. Accordingly, the 2016 sport nutrition guidelines from the American College of Sports Medicine recommend CHO intakes ≤90 g/h (from multiple-transportable CHOs, e.g., glucose/fructose mixtures), as targeted to exercise that is >2.5-3 h in duration. Although field observations report a trend for endurance athletes to consume (and experiment with) higher rates of CHO ingestion during training and racing (i.e., 120-200 g/h), the efficacy of such doses is not yet substantiated by current scientific research. Rather, contemporary research suggests that the upper limit of CHO intake could increase from 90 to 120 g/h (at least for trained participants), considering that both exogenous and whole-body rates of CHO oxidation can be increased with these higher ingestion rates. Such absolute doses may also modulate important physiological determinants of performance (e.g., durability and economy) across cycling, marathon running, and ultraendurance exercise. As such, the present paper provides a contemporary review of CHO metabolism during exercise, factors affecting exogenous CHO oxidation rates (i.e., CHO blend, ratio, format, environmental considerations, etc.) and sport-specific research (alongside personal author insights from practice), before presenting an updated and more nuanced model to guide CHO personalization strategies for endurance athletes. Directions for future research are also discussed, emphasizing the need for collaborative research to study both male and female athletes during ecologically valid exercise protocols that better address the real-world fueling challenges faced by elite athletes.
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This article explores CityHealth, an initiative of the de Beaumont Foundation and Kaiser Permanente, as a model collaboration between attorneys, public health groups and city leaders that advances a package of 12 evidence-based policies addressing key social determinants of health and centering equity.
Despite decades of research into the phenomena of athletic retirement, many modern athletes continue to report difficulties in adjusting to life beyond sport. As a result, the issue of athletic retirement has become a significant concern for those working within high-performance settings. However, there remains a distinct lack of critical attention regarding how key actors within athletes' lives (e.g., coaches) shape and impact upon their capacities to adjust to post-sport life. In this paper, we address this gap in research by presenting qualitative data from interviews with eight coaches working in the context of Olympic sport in the United Kingdom to examine their perspectives regarding the athlete retirement process. Drawing upon Foucault's conceptualization of disciplinary power-knowledge, our analysis illustrates how Olympic coaches' perspectives and experiences of athletic retirement can be linked to the modernist logic and normalizing pressures that characterize Olympic level coaching environments.
This study aimed to identify the Greatest of All Time (GOAT) athlete in running events held at the Olympic Games and World Athletics championships. The achievements of 1294 men and 824 women who won at least one medal in any sprint, hurdles, or distance event at major global championships since 1896, or set a World Record (WR) since 1912, were collated. A scoring system was used to award points, with Olympic gold medals and WRs ranked joint highest. Fewer points were awarded for Olympic silver and bronze medals and for medals in World Championships (outdoor, indoor, and cross-country). Bonus points were awarded for WR longevity and the setting of WRs during Olympic finals. Athletes were also ranked by event and within historical eras. As of March 2026, Usain Bolt (Jamaica) was ranked as the male GOAT, and the highest-scoring woman was Faith Kipyegon (Kenya). Both athletes notably won "doubles" during their careers (over 100/200 m and 1500 m/5000 m, respectively) and set WRs over both distances. Marathon, steeplechase, and hurdle specialists usually competed in one event only. In an earlier era, Paavo Nurmi (Finland) had the highest combined Olympic Games/WR score across a range of distances. Athletes who successfully competed over physiologically and tactically similar events ("doubles"), such as Bolt and Kipyegon, had a greater opportunity to become the GOAT. An increase in global competition since 1972 meant greater opportunities for winning medals, especially for women. This study provides a foundation on which future performances could be evaluated.
The step-up effect of great coaches on Olympic performance has been widely recognized, but its dynamic influence mechanism and quantitative evaluation remain methodological challenges. This study proposes a Change-Point Driven Difference-in-Differences with Decay Model ([Formula: see text]), which integrates the CUSUM algorithm, dynamic difference method (DID), and exponential decay function. The Great Coach effect's nonlinear characteristics and time attenuation rule were analyzed systematically. First, based on the improved CUSUM algorithm to detect the abrupt points of performance, the dual test mechanism of medal continuity and competition size stability was introduced to filter the pseudo-abrupt signals (such as the host effect and short-term strategic interference). Secondly, a hierarchical DID model was used to quantify the net effect of heterogeneous coach turnover events to solve the problem of traditional methods ignoring the dynamic confounding bias and run-in period. Finally, the sustainability difference of the coaching effects is revealed by the half-life model. Empirical studies show that the effect half-life of a systematic coaching system (such as Zhou Jihong coaching the Chinese diving team) is more than 20 years, while the technology-driven intervention (such as the AI tactical optimization for Japanese judo) has a half-life of only 5.3 years. The model predicts that in the 2028 Los Angeles Olympics, the introduction of great coaches will enable the Brazilian swimming team to achieve a breakthrough from 0 to 5 medals (95% CI: 4.7-6.3). This study provides an explainable and predictive framework for the allocation of coaching resources in Olympic strategy, and its methodology can be extended to dynamic causal inference in policy evaluation and organizational management.
This study examined the relationship between start order and competition outcomes in men's artistic gymnastics apparatus finals. Competition outcomes from three Olympic Games and nine World Championships were analyzed. Ordinal-based analyses, including Spearman's rank-order correlation and Kendall's tau-b, were conducted to examine the relationship between start order and final rankings. Logistic regression was used to assess the association between start order and medal attainment. In addition, Mann-Whitney U tests were used to compare final rankings between start-order groups; independent-samples t-tests were used to assess differences in Difficulty (D) scores, Execution (E) scores, and total scores; and Chi-square tests were used to evaluate associations between start-order grouping, medal attainment, and continental affiliation. Ordinal correlation and logistic regression analyses showed no significant associations between start order and final rankings or medal attainment across apparatuses. Start-order grouping had limited influence on final rankings across most apparatuses. A significant effect was observed only in the pommel horse, where second-half gymnasts achieved higher E-scores and won more medals. Medal distributions between European and non-European athletes were similar across apparatuses and start-order groupings. Overall, start-order grouping had minimal effects. However, pommel horse results highlight the importance of execution stability. The findings support the general fairness of the current judging system and Code of Points. Future research should examine warm-up procedures under revised FIG regulations and extend analyses to women's artistic gymnastics.
Haugen, T, Sandbakk, Ø, Bucher Sandbakk, S, and Tønnessen, E. Strength and speed training practices for Olympic endurance sports: Insights from world-class coaches. J Strength Cond Res 40(8): 1003-1012, 2026-This study aimed to identify common features and sport-specific variations in strength and speed training practices in Olympic endurance sports as described by world-class Norwegian coaches. A multiple case study design was used, and 12 successful male Norwegian coaches served as key informants. Together, they were responsible for athletes winning ∼400 international medals, representing long-distance running, biathlon, rowing, cross-country skiing, speed skating, road cycling, swimming, and triathlon. Data collection was based on a pragmatic 4-step procedure involving questionnaires, training logs, in-depth and semistructured interviews, followed by negotiation among researchers and coaches to assure our interpretations. The present coaches implemented strength and speed training to reduce injury risk, enhance work economy, finish/acceleration capacity, and skeletal health. The total volume of such training ranged from 20 to 200 hours·year -1 , depending on sport and contextual factors. The highest volumes and resistance loads were reached during preparation phases, and the strength and speed training were implemented at varying stages of the weekly cycle. Strength sessions typically consisted of 4-8 exercises, 2-4 sets per exercise, 5-10 repetitions per set, and up to 10 repetitions in reserve. The speed training was completed in sport-specific modality with an intensity >90% of maximal velocity. The coaches emphasized strength and speed training as supportive yet secondary to endurance development, often delegating its implementation to the athletes themselves or to specialized staff. The present insights offer valuable contributions to strength and speed training practices in endurance sports and lay the groundwork for future research exploring the effectiveness of these strategies.
This study describes the long-term development of training characteristics and physiological performance-determining variables among six world-class (Tier 5) female cross-country skiers across three decades, collectively holding 61 Olympic/World Championship medals. The skiers were divided into two groups: three world-leading (Tier 5+) athletes with ≥ 8 medals in international championships and three Tier 5 athletes with ≤ 4 medals. Self-reported training characteristics, as well as peak oxygen uptake ([Formula: see text]) and submaximal lactate threshold tests from junior to senior age were collected and analyzed retrospectively. Training was categorized into endurance, strength and speed training, with endurance training systemized using a five-zone intensity scale. While athletes exhibited individual patterns in the development of training volume from junior to senior, the increase in training volume was primarily driven by a rise in low-intensity endurance training. There was a noticeable trend that Tier 5+ athletes had a longer, more consistent increase in training volume compared to Tier 5. Among Tier 5+ athletes, [Formula: see text] values showed a positive progression from junior to senior level, whereas only one of the Tier 5 showed the same pattern. Additionally, Tier 5+ demonstrated larger improvements in speeds at a given blood lactate and heart rate level than Tier 5 throughout the investigated period (e.g., mean increase in speed at estimated lactate threshold: ~14% for Tier 5+ vs. ~ 7% for Tier 5). Keeping in mind the limitations associated with the small sample size, the development pathways to becoming a Tier 5+ skier tended to involve longer, more consistent, increases in training volume, resulting in greater improvements in both [Formula: see text] and submaximal physiological determinants than Tier 5 skiers.
In 2019, Schleu et al. showed that 400-m runners at major championships exhibited team effort gains-they ran faster in the relay than in the individual competition. However, due to low statistical power, it remains unclear whether these findings are replicable. In a replication and extension of this study, we wanted to find out whether its findings replicate in a sample of 1,718 observations from 1,270 U.S. college athletes and whether effort expenditure is driven by working in a team or the chance of valuable outcomes in the relay. As shown by linear mixed modeling and regression analyses, runners exhibited effort gains only if their relays had high medal chances and if they had not been successful in the individual competition (i.e., did not place first to third). Moreover, relay members who had been successful in the individual competition showed effort losses. Overall, effort expenditure was thus driven by rewards.
Although Depo-Provera is best known as an injectable hormonal contraceptive, the drug also served as a method of menstrual suppression for institutionalized women with intellectual disabilities in the late twentieth-century United States, even after the Food and Drug Administration refused to license it for this purpose. To understand how institutionalized women came to be injected with Depo-Provera in the 1980s, this article investigates the controversy at A School for Me, a Navajo-run institution that came under fire during a 1987 congressional hearing for administering Depo-Provera to its residents. Beyond its utility as a contraceptive, many physicians and institutional administrators saw Depo-Provera as a treatment for menstrual anxiety, a reprieve for care workers, a non-surgical substitute for sterilization, and a delayer of puberty for women with intellectual disabilities. These perceived benefits explain why some physicians and administrators championed routine injections of Depo-Provera in institutional settings, despite public backlash and concerns about the drug's potential to cause cancer. Framing Depo-Provera as a form of care enabled it to be deployed as a form of control over these women's menstruation and their bodyminds. Editor's Note: This article received the American Association for the History of Medicine 2025 Shryock Medal, an award for an outstanding, unpublished essay by a single author graduate student on any topic in the history of medicine.
Hydrogels are of great interest for the delivery of protein therapeutics as they obviate the denaturing shear forces and/or organic solvents common to other delivery systems. Dextrin, a polysaccharide derived from starch, has been largely ignored in the design of hydrogels, yet is biodegradable and can be modified to allow in situ gelation after injection by click-crosslinking. Herein, dextrin is modified with either ketone or aldehyde moieties and then click-crosslinked with poly(ethylene glycol)-tetraoxyamine to form dextrin-oxime (dexime) hydrogels. The rheological and mechanical properties are tunable by changing formulation parameters such as total dextrin weight percentage (wt.%) and pH. The hydrogels are injectable through a 30G needle, selectively degradable via α-amylase, yet stable and minimally swelling in the presence of other enzymes, including hyaluronidase and chondroitinase ABC (ChASE). The presence of low amounts of α-amylase in many fluids and tissues of the body allow for the slow degradation of dexime with minimal swelling. Dexime is particularly useful for local delivery of ChASE: an enzyme that degrades the aggregate scar formed after injury in the central nervous system. Dexime is cytocompatible and releases active ChASE both in vitro and in vivo as evidenced by chondroitin sulphate proteoglycan degradation in the spinal cord.
To investigate the associations between ocular parameters-mean keratometry (Km), spherical equivalent (SE), central corneal thickness (CCT), axial length (AL), corneal hysteresis (CH), and corneal resistance factor (CRF)-and intraocular pressure (IOP) measurements obtained by non-contact tonometry (IOPNCT), Schiøtz tonometry (IOPSchiøtz), dynamic contour tonometry (IOPDCT), corneal-compensated (IOPcc), and Goldmann-correlated IOP (IOPg) in a myopic population. Correlation and regression analyses were performed to identify the IOP measurement method least affected by ocular parameters. An optimized prediction model was then constructed based on conventional tonometry. This study included 64 patients (128 eyes). All participants underwent comprehensive ocular examinations (CCT, AL, SE, Km, CH, and CRF) and IOP measurements using multiple tonometers. Pearson correlation and multiple linear regression analyses were employed to identify key influencers on IOP readings. An optimized prediction model was subsequently developed using NCT, CCT, CH, and CRF as independent variables, and its goodness-of-fit was evaluated. Age, AL, Km, IOPSchiøtz, IOPDCT, IOPcc, and IOPg showed statistically significant differences between sexes. Multiple regression identified CRF as the strongest positive predictor for all IOP measurements (P < 0.001), while CH was a consistent negative predictor (P < 0.01). Notably, dynamic contour tonometry (DCT) demonstrated the smallest regression coefficients for CH (B = -0.745) and CRF (B = 0.812), indicating minimal influence from corneal parameters. An optimized prediction model was developed: DCT-pred = 18.657 + 0.394 × NCT - 0.008 × CCT - 0.415 × CH + 0.107 × CRF (MSE = 3.30). DCT measurements were less influenced by CCT, CH, and CRF, supporting their potential reliability for IOP assessment in patients with myopia. The optimized prediction model based on multiple regression analysis was able to predict DCT values to some extent, thereby reducing the influence of corneal biomechanical properties on IOP measurement. However, the model requires further validation and refinement in studies with larger sample sizes.
Christine A. Curcio, PhD, and Cynthia Owsley, PhD, MSPH, have been jointly honored with the 2025 Proctor Medal by ARVO. This distinguished award recognizes their 40 years of pioneering contributions to vision science and ophthalmology, especially in uncovering the early stages of age-related macular degeneration (AMD). Their unique collaboration has effectively connected basic neuroscience with clinical psychophysics, greatly transforming scientific and clinical approaches to the early detection and prevention of AMD. In their Proctor Medal Lecture, titled "The Science of Rod-Mediated Dark Adaptation, an Outcome Measure for Age-Related Macular Degeneration," Drs. Curcio and Owsley combined insights from two research careers on retinal biology, visual function, aging, and AMD.
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Opioids are commonly prescribed for acute pain. However, there is no overarching synthesis on their efficacy. We set out to conduct an overview review of the efficacy and harms of opioid analgesics for acute pain. Electronic databases were searched until 4 March 2025 without restriction for systematic reviews of randomised trials comparing opioids to placebo/no active treatment for any acute, non-malignant pain condition published since 2010. Screening, extraction and quality assessment were conducted independently by two authors. The primary outcome was pain. Secondary outcomes were adverse events. Data timepoints were immediate (≤ 3 h after administration-primary timepoint), short (> 3 to ≤ 6 h), intermediate (> 6 to ≤ 48 h) and long term (> 48 h). Random effect meta-analyses were conducted. AMSTAR 2 described review quality. Grading of Recommendations Assessment, Development and Evaluation determined evidence certainty. We included 59 reviews. There was high certainty some opioids (morphine, oxycodone, tramadol, papaveretum) reduced acute abdominal pain at immediate term (mean difference [MD] - 18.4, 95% CI - 31.9 to - 5.0) compared with placebo. However, there were no harms data. At immediate term, there was moderate certainty opioids reduced pain including dental surgery (MD - 19.5, 95% CI - 25.0 to - 14.0), and myringotomy (MD - 15.0, 95% CI - 19.6 to - 10.4). However, harms data were only available for dental surgery, finding no increased risk of adverse events. Oral opioids provided only very small pain relief for acute musculoskeletal pain at intermediate term (MD - 8.9, 95% CI - 13.5 to - 4.3; moderate certainty) but increased the risk of adverse events (risk difference [RD] 0.1, 95% CI 0.0 to 0.2; moderate certainty). Some opioids are not consistently efficacious across timepoints. Opioid analgesics are efficacious in reducing pain in some acute conditions. ROSPERO CRD42018109733.
Theda Borde, recipient of the 2025 Salomon Neumann Medal of the German Society for Social Medicine and Prevention (DGSMP), holds a degree in political science and a doctorate in Public Health. She served as Professor and, for a period, as Rector at the Alice Salomon University of Applied Sciences Berlin. Her research and teaching focus on the social determinants of health, gender and health, interprofessional collaboration in healthcare, and migration and health. Four core principles that shaped the work of Salomon Neumann also characterize Theda Borde's scholarly contributions: addressing the needs of socioeconomically disadvantaged populations, generating scientific evidence on their health status, translating research findings into practice, and taking a public stance - particularly in times of populist resistance. Theda Borde's work, however, extends beyond Neumann's historical framework: participation and co-creation are central to her understanding of health equity and the advancement of social justice. Theda Borde, die Empfängerin der Salomon-Neumann-Medaille 2025 der Deutschen Gesellschaft für Sozialmedizin und Prävention (DGSMP), ist studierte Politologin und promovierte im Bereich Public Health. Sie war Professorin an der Alice Salomon Hochschule Berlin und übernahm dort zeitweise das Amt der Rektorin. Ihre Schwerpunkte in Forschung und Lehre umfassen die sozialen Determinanten von Gesundheit, Geschlecht und Gesundheit, interprofessionelle Kooperation in der Gesundheitsversorgung sowie Migration und Gesundheit. Vier zentrale Elemente aus dem Werk von Salomon Neumann prägen auch Theda Bordes wissenschaftliches Lebenswerk: sozioökonomisch benachteiligte Bevölkerungsgruppen in den Blick zu nehmen, wissenschaftliche Evidenz zu ihrer gesundheitlichen Lage zu schaffen, Forschungsergebnisse in die Praxis umzusetzen und politisch Stellung zu beziehen – insbesondere dann, wenn es populistischen Gegenwind gibt. Dabei – und hier reicht Theda Borde über Salomon Neumann und seine Zeit hinaus – sind für sie Teilhabe und Ko-Kreation von zentraler Bedeutung.