Fueling strategies to optimize performance: training high or training low?

Availability of carbohydrate as a substrate for the muscle and central nervous system is critical for the performance of both intermittent high-intensity work and prolonged aerobic exercise. Therefore, strategies that promote carbohydrate availability, such as ingesting carbohydrate before, during and after exercise, are critical for the performance of many sports and a key component of current sports nutrition guidelines. Guidelines for daily carbohydrate intakes have evolved from the "one size fits all" recommendation for a high-carbohydrate diets to an individualized approach to fuel needs based on the athlete's body size and exercise program. More recently, it has been suggested that athletes should train with low carbohydrate stores but restore fuel availability for competition ("train low, compete high"), based on observations that the intracellular signaling pathways underpinning adaptations to training are enhanced when exercise is undertaken with low glycogen stores. The present literature is limited to studies of "twice a day" training (low glycogen for the second session) or withholding carbohydrate intake during training sessions. Despite increasing the muscle adaptive response and reducing the reliance on carbohydrate utilization during exercise, there is no clear evidence that these strategies enhance exercise performance. Further studies on dietary periodization strategies, especially those mimicking real-life athletic practices, are needed.

Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object.

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.

Financial Value Analysis of Surgical Residency Programs: An Argument Against Replacement.

OBJECTIVE: To quantify the replacement cost of patient care provided by surgical residents and build a Graduate Medical Education (GME) value analysis model. DESIGN: Our Graduate Medical Education Executive Steering Committee designed a resident replacement cost model, based on patient care hours (adjusted for educational activities and a clinical efficiency factor, differential cost of faculty supervision for residents vs. APPs, and current program financials (revenue minus expenses). Strategic value planning included: academic productivity (local and national conference presentations, book chapters and publications and Senior Staff recruitment and retention. SETTING: Department of Surgery at Baylor Scott & White Medical Center, a tertiary institution located in Temple, TX. PARTICIPANTS: Our replacement model was applied to a sample 30-position residency program. RESULTS: Modeling a 30-position residency program, replacement cost approaches 4.5 million dollars, based on a 1:3 Senior Staff-to-APP replacement ratio. A complete APP replacement complement has a projected cost of 3.1 million dollars, while replacement with Senior Staff approaches 9 million dollars. CONCLUSIONS: We present a novel model for residency value analysis allowing for reproducible and standardized results across multiple residency programs. Challenges inherent to GME, such as clinical efficiency and the cost of faculty supervision, are accounted for. Quantifying resident replacement cost and financial value is a powerful tool when discussing institutional workforce planning within the current financial climate of healthcare.