Lipids as a fuel source for energy supply during submaximal exercise originate from subcutaneous adipose tissue derived fatty acids (FA), intramuscular triacylglycerides (IMTG), cholesterol and dietary fat. These sources of fat contribute to fatty acid oxidation (FAox) in various ways. The regulation and utilization of FAs in a maximal capacity occur primarily at exercise intensities between 45 and 65% VO2max, is known as maximal fat oxidation (MFO), and is measured in g/min. Fatty acid oxidation occurs during submaximal exercise intensities, but is also complimentary to carbohydrate oxidation (CHOox). Due to limitations within FA transport across the cell and mitochondrial membranes, FAox is limited at higher exercise intensities. The point at which FAox reaches maximum and begins to decline is referred to as the crossover point. Exercise intensities that exceed the crossover point (~65% VO2max) utilize CHO as the predominant fuel source for energy supply. Training status, exercise intensity, exercise duration, sex differences, and nutrition have all been shown to affect cellular expression responsible for FAox rate. Each stimulus affects the process of FAox differently, resulting in specific adaptions that influence endurance exercise performance. Endurance training, specifically long duration (>2 h) facilitate adaptations that alter both the origin of FAs and FAox rate. Additionally, the influence of sex and nutrition on FAox are discussed. Finally, the role of FAox in the improvement of performance during endurance training is discussed.

This study assessed how seasonal transitions and coaching influence affect aerobic capacity (AC) and body composition across the annual training cycle (ATC). Eleven division 1 female soccer players were tested after five predesignated time blocks (B1–B5): post-season 2016 (B1), nine-week transition (B2), spring season (B3), pre-season (B4), and post-season 2017 (B5). Height, weight, and body composition (fat-free mass (FFM)) were measured prior to a standardized 5 min treadmill running and dynamic movement warm up before a maximal AC test. Statistical analysis included a 4 × 5 repeated-measures analysis of variance (ANOVA) (dependent variable × time) with the Fishers Least Significant Difference (LSD) post-hoc test when relevant; data are presented as mean ± standard deviation, effect size (ES), and percent change (%). The statistical analysis revealed that the ATC had a significant main effect on AC and FFM (F_3,4 2.81, p = 0.001; η² = 0.22). There were significant increases in AC across the transition period (B1–B2) with reduced training volume (∆ + 12.9%, p = 0.001; ES = 0.50) while AC and FFM peaked after the spring season with directed concurrent training paired with adequate rest B1–B3 (∆ + 16.4%, p < 0.01; ES = 0.81). AC decreased across the pre-season with indirect training (B3–B4) (∆ − 7.0%, p = 0.02; ES = 0.50) and remained suppressed without change (p > 0.05) across the competitive season (B4–B5). Rest, concurrent training, and directed training positively affected AC, while indirect training and high training loads with little rest negatively affected AC.

Background: African Americans (AA) are disproportionally affected by hypertension (HTN). Gut microbiome metabolites (e.g., butyrate) may mediate the relationship between the microbiome and blood pressure (BP). Previous research reports a consistent indirect relationship between gut butyrate, a product of gut microbial nutrient fermentation, and BP. Thus, this study assessed the relationship between individual diet intake on BP changes after a butyrate treatment. Methods: AA aged 30–50 with HTN underwent treatment with a blinded placebo (5 mmol) and butyrate enema (80 mmol) with a one-week washout period. Ambulatory BP monitors collected measures up to 24 h post-enema. The Nutrition Data System for Research was used to assess diet and Healthy Eating Index (HEI-2015) scores from diet records. Paired t-tests and Kendall’s correlation tests determined group differences and relationships between variables (p < 0.05). Results: Positive correlations were found between other vegetables and 24 h diastolic BP (r = 0.64), daytime diastolic BP (r = 0.68), and MAP (r = 0.72). Positive correlations were also found between 24 h systolic BP and HEI-2015 greens and beans sub-scores (r = 0.64) and 24 h DBP and total vegetables (r = 0.64). Negative correlations were found between nighttime arterial stiffness and total grain intake (r = −0.71). Conclusion: These data suggest diet impacts BP measures in response to acutely increasing gut butyrate. These results provide preliminary evidence linking food groups, not individual nutrients, with BP outcomes and gut butyrate availability.

The purpose of this study was to investigate the relationship between low energy availability (LEA) and nutritional content with high blood pressure (HBP) in African American Division I athletes. Twenty-three D1 African American pre-season athletes were recruited to participate. HBP was defined as >120 systolic blood pressure (BP) and <80 diastolic BP. Athletes self-reported nutritional intake using a non-consecutive 3-day food recall which was then reviewed by a sports dietitian. LEA was evaluated as total energy intake—total daily energy expenditure (TDEE), which was predicted. Additionally, micronutrients were evaluated. A statistical analysis relied on Spearman correlation (R), standardized mean difference with 95% confidence interval, mean ± SD, and odds ratios (OR). Correlation values were categorized: 0.20–0.39 = low; 0.40–0.69 = moderate; 0.70–1.0 = strong. A moderate relationship was observed between HBP and LEA (R = 0.56) with 14/23 having HBP. Of the 14 athletes observed with HBP, 78.5% (11/14) were calorically deficient (−529 ± 695 kcal) with an OR of 7.2. Micronutrient intake deficiencies were ubiquitous among the 23 HBP athletes: poly-unsaturated fatty acid −29.6%; omega-3 −26.0%; iron −46.0%; calcium −25.1%; and sodium −14.2%, amongst others. LEA and micronutrient deficiencies may contribute to HBP in Black D1 athletes, which has been shown to be the most common modifiable risk factor to decrease the risk of sudden cardiac death.

Previous research has shown that acute competition training stress negatively affects neuromuscular function which can perpetuate a predisposition to injury. This study's aim was to investigate the effect of accumulated competition training stress effect on neuromuscular function and incidence of increased injury risk in uninjured female D1 soccer players. Neuromuscular function was evaluated in fifteen female division I soccer athletes who played >85% of competitive season competitions who were tested for mobility/stability, leg length symmetry, and vertical power at three different points across the competitive season (pre, mid, and post time blocks). Leg length symmetry was measured from the anterior superior iliac spine to the lateral malleolus prior to Y-balance testing. The Y-balance testing measures unilateral anterior, posteromedial, and posterolateral reach achieved in single leg stance using metrics that include L/R normalized composite reach (NCOMP), L/R normalized antiorior reach (NANT), and L/R NCOMP/NANT segmental differences across time. Injury risk was evaluated using validated objective criteria that included: (NCOMP total reach <94% of limb length^*3), (NANT reach distance 4.0. Maximal vertical power (MVP) was measured via vertical jump. Multiple repeated measures ANOVAs evaluated NCOMP, NANT, MVP, and leg length symmetry across time with LSD post hoc testing when relevant (X ± SD). A significant main effect was found [F_{(1, 14)} = 62.92, p < 0.001; η² =0.82] with training stress and neuromuscular function without affecting maximal vertical power. Eighty percent of subject's bilateral NCOMP scores fell below the YBT reach standard at midseason (ES = 0.95, p = 0.02) while all subjects NANT reach distance remained below the reach threshold (ES = 0.74, p = 0.003) indicating a 6.5× and 2.5× greater injury risk, respectively. Competition stress affected neuromuscular function without affecting maximal power, which negatively impacted stability and increased injury risk.

Hyaluronic acid (HA) contributes to extracellular matrix viscosity and fiber regeneration. HA role in resistance training (RT) performance adaptations is unclear. RT men performed power training (nonfunctional overreaching (NFOR) or normal training (CG)) over 7.5 days. Post RT, the CG improved power while NFOR did not with HA content decreasing 34.5% in NFOR with no change in CG. HA is critical for muscular recovery; decreased HA may contribute to impaired power adaptations with NFOR RT. Novelty: Nonfunctional over-reaching decreases muscular hyaluronic acid.