Background In this Position Statement, the International Society of Sports Nutrition (ISSN) provides an objective and critical review of the literature pertinent to nutritional considerations for training and racing in single-stage ultra-marathon. Recommendations for Training. i) Ultra-marathon runners should aim to meet the caloric demands of training by following an individualized and periodized strategy, comprising a varied, food-first approach; ii) Athletes should plan and implement their nutrition strategy with sufficient time to permit adaptations that enhance fat oxidative capacity; iii) The evidence overwhelmingly supports the inclusion of a moderate-to-high carbohydrate diet (i.e., ~ 60% of energy intake, 5–8 g·kg− 1·d− 1) to mitigate the negative effects of chronic, training-induced glycogen depletion; iv) Limiting carbohydrate intake before selected low-intensity sessions, and/or moderating daily carbohydrate intake, may enhance mitochondrial function and fat oxidative capacity. Nevertheless, this approach may compromise performance during high-intensity efforts; v) Protein intakes of ~ 1.6 g·kg− 1·d− 1 are necessary to maintain lean mass and support recovery from training, but amounts up to 2.5 g.kg− 1·d− 1 may be warranted during demanding training when calorie requirements are greater; Recommendations for Racing. vi) To attenuate caloric deficits, runners should aim to consume 150–400 Kcal·h− 1 (carbohydrate, 30–50 g·h− 1; protein, 5–10 g·h− 1) from a variety of calorie-dense foods. Consideration must be given to food palatability, individual tolerance, and the increased preference for savory foods in longer races; vii) Fluid volumes of 450–750 mL·h− 1 (~ 150–250 mL every 20 min) are recommended during racing. To minimize the likelihood of hyponatraemia, electrolytes (mainly sodium) may be needed in concentrations greater than that provided by most commercial products (i.e., > 575 mg·L− 1 sodium). Fluid and electrolyte requirements will be elevated when running in hot and/or humid conditions; viii) Evidence supports progressive gut-training and/or low-FODMAP diets (fermentable oligosaccharide, disaccharide, monosaccharide and polyol) to alleviate symptoms of gastrointestinal distress during racing; ix) The evidence in support of ketogenic diets and/or ketone esters to improve ultra-marathon performance is lacking, with further research warranted; x) Evidence supports the strategic use of caffeine to sustain performance in the latter stages of racing, particularly when sleep deprivation may compromise athlete safety.

BackgroundThe cardio-metabolic and antioxidant health benefits of caffeinated green tea (GT) relate to its catechin polyphenol content. Less is known about decaffeinated extracts, particularly in combination with exercise. The aim of this study was therefore to determine whether a decaffeinated green tea extract (dGTE) positively influenced fat oxidation, body composition and exercise performance in recreationally active participants.MethodsFourteen, recreationally active males participated in a double-blind, placebo-controlled, parallel design intervention (mean ± SE; age = 21.4 ± 0.3 yrs; weight = 76.37 ± 1.73 kg; body fat = 16.84 ± 0.97%, peak oxygen consumption [] = 3.00 ± 0.10 L·min−1). Participants were randomly assigned capsulated dGTE (571 mg·d−1; n = 7) or placebo (PL; n = 7) for 4 weeks. Following body composition and resting cardiovascular measures, participants cycled for 1 hour at 50% , followed by a 40 minute performance trial at week 0, 2 and 4. Fat and carbohydrate oxidation was assessed via indirect calorimetry. Pre-post exercise blood samples were collected for determination of total fatty acids (TFA). Distance covered (km) and average power output (W) were assessed as exercise performance criteria.ResultsTotal fat oxidation rates increased by 24.9% from 0.241 ± 0.025 to 0.301 ± 0.009 g·min−1 with dGTE (P = 0.05; ηp2 = 0.45) by week 4, whereas substrate utilisation was unaltered with PL. Body fat significantly decreased with dGTE by 1.63 ± 0.16% in contrast to PL over the intervention period (P < 0.001; ηp2 = 0.84). No significant changes for FFA or blood pressure between groups were observed. dGTE resulted in a 10.9% improvement in performance distance covered from 20.23 ± 0.54 km to 22.43 ± 0.40 km by week 4 (P < 0.001; ηp2 = 0.85).ConclusionsA 4 week dGTE intervention favourably enhanced substrate utilisation and subsequent performance indices, but did not alter TFA concentrations in comparison to PL. The results support the use of catechin polyphenols from dGTE in combination with exercise training in recreationally active volunteers.

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Gastrointestinal (GI) ischemia during exercise is associated with luminal permeability and increased systemic lipopolysaccharides (LPS). This study aimed to assess the impact of a multistrain pro/prebiotic/antioxidant intervention on endotoxin unit levels and GI permeability in recreational athletes. Thirty healthy participants (25 males, 5 females) were randomly assigned either a multistrain pro/prebiotic/antioxidant (LAB4ANTI; 30 billion CFU·day−1 containing 10 billion CFU·day−1 Lactobacillus acidophilus CUL-60 (NCIMB 30157), 10 billion CFU·day−1 Lactobacillus acidophillus CUL-21 (NCIMB 30156), 9.5 billion CFU·day−1 Bifidobacterium bifidum CUL-20 (NCIMB 30172) and 0.5 billion CFU·day−1 Bifidobacterium animalis subspecies lactis CUL-34 (NCIMB 30153)/55.8 mg·day−1 fructooligosaccharides/ 400 mg·day−1 α-lipoic acid, 600 mg·day−1 N-acetyl-carnitine); matched pro/prebiotic (LAB4) or placebo (PL) for 12 weeks preceding a long-distance triathlon. Plasma endotoxin units (via Limulus amebocyte lysate chromogenic quantification) and GI permeability (via 5 h urinary lactulose (L): mannitol (M) recovery) were assessed at baseline, pre-race and six days post-race. Endotoxin unit levels were not significantly different between groups at baseline (LAB4ANTI: 8.20 ± 1.60 pg·mL−1; LAB4: 8.92 ± 1.20 pg·mL−1; PL: 9.72 ± 2.42 pg·mL−1). The use of a 12-week LAB4ANTI intervention significantly reduced endotoxin units both pre-race (4.37 ± 0.51 pg·mL−1) and six days post-race (5.18 ± 0.57 pg·mL−1; p = 0.03, ηp2 = 0.35), but only six days post-race with LAB4 (5.01 ± 0.28 pg·mL−1; p = 0.01, ηp2 = 0.43). In contrast, endotoxin units remained unchanged with PL. L:M significantly increased from 0.01 ± 0.01 at baseline to 0.06 ± 0.01 with PL only (p = 0.004, ηp2 = 0.51). Mean race times (h:min:s) were not statistically different between groups despite faster times with both pro/prebiotoic groups (LAB4ANTI: 13:17:07 ± 0:34:48; LAB4: 12:47:13 ± 0:25:06; PL: 14:12:51 ± 0:29:54; p > 0.05). Combined multistrain pro/prebiotic use may reduce endotoxin unit levels, with LAB4ANTI potentially conferring an additive effect via combined GI modulation and antioxidant protection.

Pulmonary hypertension (PH) is a relatively misunderstood disease, partly related to the fact that many perceive PH to be a singular diagnosis. An unintended consequence of this is the misapplication of the role of the Doppler-Echocardiographic (DE) examination, as well as an underappreciation for its ability to help discern PH pathophysiology prior to right heart catheterization. Since DE often serves as the “gatekeeper” to invasive right heart catheterization, misinterpretation of the DE can lead to missed or delayed diagnosis with devastating consequences. Too often, the primary or nearly exclusive focus of the DE examination is placed on the pulmonary artery pressure estimation. Two main issues with this approach are that Doppler pressure estimations can be inaccurate and even when accurate, without integration of additional 2-D and Doppler information, the clinician will often still not appreciate the pathophysiology of the PH nor its clinical significance. This review will focus on the 2-D and Doppler features necessary to assess pulmonary vascular disease (PVD), discern the salient differences between PVD and pulmonary venous hypertension (PVH), and how to integrate these key DE parameters such that PH pathophysiology can be determined noninvasively and early in the patient workup. Overreliance on any single DE metric, and especially PA pressure estimation, detracts from the overall diagnostic potential of the DE examination. Integrating the relative balance of right and left heart findings, along with proper Doppler interpretation provides a wealth of clinical and pathophysiologic insight prior to invasive hemodynamic assessment. The end results are heightened awareness and improved identification of which patients should be referred for further invasive testing, as well the use of the DE information to compliment the findings from invasive testing.

BackgroundWhilst exogenous carbohydrate oxidation (CHOEXO) is influenced by mono- and disaccharide combinations, debate exists whether such beverages enhance fluid delivery and exercise performance. Therefore, this study aimed to ascertain CHOEXO, fluid delivery and performance times of a commercially available maltodextrin/ fructose beverage in comparison to an isocaloric maltodextrin beverage and placebo.MethodsFourteen club level cyclists (age: 31.79 ± 10.02 years; height: 1.79 ± 0.06 m; weight: 73.69 ± 9.24 kg; VO2max: 60.38 ± 9.36 mL · kg·-1 min-1) performed three trials involving 2.5 hours continuous exercise at 50% maximum power output (Wmax: 176.71 ± 25.92 W) followed by a 60 km cycling performance test. Throughout each trial, athletes were randomly assigned, in a double-blind manner, either: (1) 1.1 g · min-1 maltodextrin + 0.6 g · min-1 fructose (MD + F), (2) 1.7 g · min-1 of maltodextrin (MD) or (3) flavoured water (P). In addition, the test beverage at 60 minutes contained 5.0 g of deuterium oxide (2H2O) to assess quantification of fluid delivery. Expired air samples were analysed for CHOEXO according to the 13C/12C ratio method using gas chromatography continuous flow isotope ratio mass spectrometry.ResultsPeak CHOEXO was significantly greater in the final 30 minutes of submaximal exercise with MD + F and MD compared to P (1.45 ± 0.09 g · min-1, 1.07 ± 0.03 g · min-1and 0.00 ± 0.01 g · min-1 respectively, P < 0.0001), and significantly greater for MD + F compared to MD (P = 0.005). The overall appearance of 2H2O in plasma was significantly greater in both P and MD + F compared to MD (100.27 ± 3.57 ppm, 92.57 ± 2.94 ppm and 78.18 ± 4.07 ppm respectively, P < 0.003). There was no significant difference in fluid delivery between P and MD + F (P = 0.078). Performance times significantly improved with MD + F compared with both MD (by 7 min 22 s ± 1 min 56 s, or 7.2%) and P (by 6 min 35 s ± 2 min 33 s, or 6.5%, P < 0.05) over 60 km.ConclusionsA commercially available maltodextrin-fructose beverage improves CHOEXO and fluid delivery, which may benefit individuals during sustained moderate intensity exercise. The greater CHOEXO observed when consuming a maltodextrin-fructose beverage may support improved performance times.

The purpose of this investigation was to compare two different methods of assessing body composition (i.e., a multi-frequency bioelectrical impedance analysis (MF-BIA) and dual-energy x-ray absorptiometry (DXA)) over a four-week treatment period in exercise-trained men and women. Subjects were instructed to reduce their energy intake while maintaining the same exercise regimen for a period of four weeks. Pre and post assessments for body composition (i.e., fat-free mass, fat mass, percent body fat) were determined via the MF-BIA and DXA. On average, subjects reduced their energy intake by ~18 percent. The MF-BIA underestimated fat mass and percentage body fat and overestimated fat-free mass in comparison to the DXA. However, when assessing the change in fat mass, fat-free mass or percent body fat, there were no statistically significant differences between the MF-BIA vs. DXA. Overall, the change in percent body fat using the DXA vs. the MF-BIA was −1.3 ± 0.9 and −1.4 ± 1.8, respectively. Our data suggest that when tracking body composition over a period of four weeks, the MF-BIA may be a viable alternative to the DXA in exercise-trained men and women.

The aim of the present study was to map and grade evidence for the relationships between telomere length with a diverse range of health outcomes, using an umbrella review of systematic reviews with meta-analyses. We searched for meta-analyses of observational studies reporting on the association of telomere length with any health outcome (clinical disease outcomes and intermediate traits). For each association, random-effects summary effect size, 95% confidence interval (CI), and 95% prediction interval were calculated. To evaluate the credibility of the identified evidence, we assessed also heterogeneity, evidence for small-study effect and evidence for excess significance bias. Twenty-one relevant metaanalyses were identified reporting on 50 different outcomes and including a total of 326 observational studies. The level of evidence was high only for the association of short telomeres with higher risk of gastric cancer in the general population (relative risk, RR=1.95, 95%CI: 1.68-2.26), and moderate for the association of shorter telomeres with diabetes or with Alzheimer's disease, even if limited to meta-analyses of case-control studies. There was weak evidence for twenty outcomes and not significant association for 27 health outcomes.The present umbrella review demonstrates that shorter telomere length may have an important role in incidence gastric cancer and, probably, diabetes and Alzheimer's disease.At the same time, conversely to general assumptions, it does not find strong evidence supporting the notion that shorter telomere length plays an important role in many health outcomes that have been studied thus far.