Gastrointestinal (GI) disturbances are a prevalent cause of marathon related complaints, and in extreme cases can promote life-threatening conditions such as exertional heat stroke. Our aim was to study intestinal cell injury [via intestinal fatty acid binding protein (I-FABP)] and perceived GI distress symptoms among marathon runners. We also examined potential risk factors (e.g., inadequate sleep) that could exacerbate GI disturbances in healthy, trained endurance runners. This was a parallel mixed-methods study design. 2019 Boston Marathon participants were recruited via email and subjects completed surveys before the race describing demographics and training history. Participants completed a GI questionnaire to assess presence and severity of symptoms, a survey regarding risk factors (e.g., recent illness, medications) that could promote GI disturbances, and provided a urine sample at three time points (immediately pre-race, post-race, and 24-h post-race). Due to weather, blood samples were only collected immediately and 24-h post-race. A total of 40 runners (males: n = 19, age = 44.9 ± 10.8 years; females: n = 21, age = 44.8 ± 10.6 years) completed this study. I-FABP significantly decreased from post-race (3367.5 ± 2633.5 pg/mL) to 24-h post-race (1657.3 ± 950.7 pg/mL, t (39) = −4.228, p < .001, d = −.669). There was a significant difference in overall GI symptom scores across the three time points (F (2, 39) = 41.37, p < .001). The highest average score occurred post-race (.84 ± .68), compared to pre-race (.09 ± .12) and 24-h post-race (.44 ± .28). Post-race I-FABP (r = .31, p = .048) and post-race urine specific gravity (r = .33, p = .041) were significantly correlated with post-race GI symptom scores. Our study provides further support to the individualized nature of GI disturbances, with participants experiencing a wide range of risk factors that can influence the extent of GI damage and perceived symptoms during and after exercise.

High total energy expenditure (TEE) and rate of water turnover (rH₂O) using doubly labeled water (²H₂¹⁸O) have been reported during single-stage and multistage ultraendurance events. At the 161-km distance, less is known about the interaction of TEE, rH₂O, and ad libitum energy/fluid intake. This is especially true during the postrace recovery window. Purpose: To measure TEE, rH₂O, and ad libitum energy/fluid intake during a 161-km ultramarathon while extending the TEE and rH₂O measurement window to a 7-day postrace period. Methods: Doubly labeled water was used to monitor TEE and rH₂O in 2 male ultrarunners (R1, R2) during a 161-km ultramarathon. Self-reported energy/fluid intake was recorded at crew-accessible aid stations. Results: Both runners completed the race in 32.8 hours, and TEE over this period was 65.8 MJ (6.5 × basal metabolic rate [BMR], 15,723 kcal, 11,225 kcal·24 h⁻¹) in R1 and 66.5 MJ (7.4 ×BMR, 15,888 kcal, 11,293 kcal·24 h⁻¹) in R2. Race energy intake for both runners approximated 50% of TEE, with reported fluid consumption of 21.8 L and 15.7 L for R1 and R2, respectively. rH₂O during the race was 14.6 L in R1 and 15.5 L in R2. During the 7-day postrace period, total TEE and rH₂O were 94.7 MJ (1.9 ×BMR, 22,634 kcal, 3245 kcal·d⁻¹) and 41.8 L for R1 and 80.0 MJ (1.8 ×BMR, 19,116 kcal, 2721 kcal·d⁻¹) and 24.0 L for R2, respectively. Conclusion: These data illustrate the expected nutrient and fluid budgets for ultramarathons and describe the challenge of restoring acute negative energy balance following these events.

Marching band (MB) artists are often part of the general student population and not required to complete a pre-participation health screening to identify predisposing medical conditions or risks for injury/illness. Anecdotally, exertional heat illnesses (EHI) are a concern for MB artists. As more athletic trainers provide MB healthcare, research is needed on EHI occurrence and MB associated EHI risk factors. We utilized an exploratory cross-sectional study design to determine EHI risk factors, including previous EHI occurrence, among collegiate MB artists. MB artists (n ​= ​1 207; age ​= ​[19.6 ​± ​1.3] years) actively participating in their college/university's MB during the 2019 football season completed an online survey to characterize demographics, medical history, medication and supplement use, and nutrition behaviors. Chi-square and binomial logistical regressions assessed associations between categorical variables. Previous EHI was reported by 50.6% of MB artists, with 466 (76.3%) experiencing exertional heat exhaustion and 31 (5.1%) exertional heat stroke. More females reported exertional heat exhaustion overall (68.2%, p ​< ​0.001) and in the previous year (73.3%, p ​< ​0.001). Experiencing a previous EHI was significantly associated with having a mood/neurological condition (63.5%, p ​< ​0.001), diagnosed (74.3%, p ​= ​0.004) or perceived eating disorder (66.7%, p ​< ​0.001), and taking prescription medications (59.4%, p ​< ​0.001), over-the-counter medications (58.9%, p ​= ​0.002), and supplements (55.4%, p ​= ​0.037). Half of collegiate MB artists reported experiencing previous EHIs and engaged in behaviors known to increase EHI risk. MB artists should complete pre-participation examinations to identify pre-existing medical conditions and risks for adverse medical events. Healthcare providers working with MB artists should develop policies and procedures to mitigate EHI risks and occurrence.

Exercise-associated hyponatremia (EAH) is commonly observed in endurance athletes, where prolonged physical exertion combined with being unaware of personal hydration needs can lead to excessive water consumption or inadequate sodium intake. Marching band (MB) is an emerging setting for sports medicine professionals. However, there is little research on non-musculoskeletal illnesses among these performing artists. This study is part of a larger cross-sectional study and seeks to examine whether MB artists have previously experienced EAH and the presence of known EAH risk factors (e.g., pre-existing medical conditions, medication use, nutritional behaviors). Active collegiate MB members (n = 1207; mean age = 19.6 ± 1.3 years) completed an online survey that characterized demographics, medical history, and nutrition behaviors. Statistical analyses included descriptives (mean, standard deviation) and frequencies for all data. Binomial logistic regressions analyzed the relationship and determined the odds ratio (OR) between previous EAH and EAH risk factors. Participants were from 23 different states, predominately White (82.9%), female (56.7%), and at NCAA Division I institutions (92%). A total of 74 (6.1%) participants reported previously experiencing EAH, 32 (43.2%) within the past year. Previous EAH occurrence was greatest among individuals who had kidney conditions (χ²(1) = 5.920, R² = 0.013, OR = 15.708, p = 0.015); mood/neurological conditions (χ²(1) = 7.508, R² = 0.017, OR = 2.154, p = 0.006), particularly anxiety (χ²(1) = 7.651, R² = 0.017, OR = 3.590, p = 0.006); used mental health medications (χ²(1) = 7.512, R² = 0.017, OR = 2.220, p = 0.006), particularly selective serotonin reuptake inhibitors (χ²(1) = 13.502, R² = 0.030, OR = 3.297, p < 0.001); and who dieted (χ²(1) = 6.121, R² = 0.014, OR = 1.913, p = 0.013) or perceived they had an eating disorder (χ²(1) = 9.502, R² = 0.021, OR = 2.729, p = 0.002). Healthcare providers should be aware that MB artists may have pre-existing medication conditions, use medication, and have inadequate nutrition. Targeted hydration and nutritional education for MB artists is essential for effective prevention and early EAH recognition, improving health and performance for MB artists within demanding environments.

Background: There is a lack of research investigating the effect of hydration status or intermuscular glycogen content on ultrasound-derived muscle quality imaging in younger adults. Purpose: To examine the effects of varied hydration and muscle glycogen status on ultrasound-measured vastus lateralis (VL) cross-sectional area (CSA) and echo intensity (EI). Materials and Methods: Thirteen young adults (Age: 23 ± 4.2 yrs; Height: 168.5 ± 6.8 cm; Weight: 76.2 ± 17.1 kg) participated in five experimental visits: (1) Baseline (regular dietary intake); (2) hypohydrated and normal carbohydrate (CHO) intake (HH-NC); (3) euhydrated and normal CHO intake (EH-NC); (4) hypohydrated and CHO restriction (HH-CR); and (5) euhydrated and CHO restriction (EH-CR) conditions. Ultrasound imaging of the right VL was used to assess CSA and EI at each visit. A two-way repeated measures ANOVA with Holm adjusted post hoc test was performed for statistical analysis. Results: Body mass was affected by both hydration and carbohydrate restriction (both p < 0.001), while Usg was greater during hypohydration (p < 0.001). VLCSA was lower following carbohydrate restriction (p = 0.010), independent of hydration status, whereas VLEI was not significantly affected by hydration, carbohydrate restriction, or their interaction (all p ≥ 0.063). Conclusions: Overall, these findings suggest that an individual’s hydration and CHO intake may influence ultrasound-derived muscle CSA assessments. Future research should continue to explore the sensitivity of EI and CSA to determine the impact of these findings in both clinical and research environments.