Alternate-Day Low Energy Availability During Spring Classics in Professional Cyclists.

Purpose: To assess energy and carbohydrate (CHO) availability and changes in blood hormones in 6 professional male cyclists over multiple single-day races.

Methods: The authors collected weighed-food records, power-meter data, and morning body mass measurements across 8 d. CHO intakes were compared with contemporary guidelines.

Organization of Dietary Control for Nutrition-Training Intervention Involving Periodized Carbohydrate Availability and Ketogenic Low-Carbohydrate High-Fat Diet.

The authors describe the implementation of a 3-week dietary intervention in elite race walkers at the Australian Institute of Sport, with a focus on the resources and strategies needed to accomplish a complex study of this scale. Interventions involved: traditional guidelines of high carbohydrate (CHO) availability for all training sessions; a periodized CHO diet which integrated sessions with low and high CHO availability within the same total CHO intake; and a ketogenic low-CHO high-fat diet. Seven-day menus and recipes were constructed for a communal eating setting to meet nutritional goals as well as individualized food preferences and special needs.

Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers.

Key Points: Three weeks of intensified training and mild energy deficit in elite race walkers increases peak aerobic capacity independent of dietary support. Adaptation to a ketogenic low carbohydrate, high fat (LCHF) diet markedly increases rates of whole-body fat oxidation during exercise in race walkers over a range of exercise intensities. The increased rates of fat oxidation result in reduced economy (increased oxygen demand for a given speed) at velocities that translate to real-life race performance in elite race walkers.