The cardiovascular, cardiopulmonary and metabolic demands of a simulated snowboard cross competition – An exploratory case study

Abstract

During a snowboard cross competition a successful athlete completes multiple time trials and race heats over the course of a day with varied recovery times. Understanding the demands of a snowboard cross competition can allow for potential performance limiting factors to be identified so that training, nutrition and/or ergogenic interventions can be developed to improve athletic performance. Unfortunately, as of yet, no studies have directly measured the cardiovascular, cardiopulmonary and/or metabolic demands of snowboard cross run or competition. Therefore, as an exploratory case study, we recruited two elite (ranked in the top 5 in the United States) youth (age 16-17 years old) snowboard cross athletes to participant in a case series to fill this knowledge gap. Prior to the study both athletes completed a treadmill based ventilatory threshold and aerobic power test to determine physiological capacity and bioenergetic cut puts. Two days later athletes then took part in a simulated snowboard cross competition that mimicked the 2017 male and female US nationals (2 course inspections, 2 time trials and 2-3 race heats) on an FIS certified course while wearing a portable metabolic cart and heart rate monitor. Averaged race values of oxygen consumption, respiratory exchange, ventilatory rate, breathing frequency, tidal volume and oxygen delivery per heartbeat were reported and referenced to treadmill tests. Comparisons were then made over the course of the competition and between the fastest and slowest runs for both athletes. Results indicate that 1) athletes primarily utilize anaerobic glycolysis at intensities between ventilatory thresholds 1 & 2, 2) oxidative metabolism was impaired due to restricted breathing frequency that may be a necessary component of snowboard cross technique, 3) athletes fully recovered between time trials but not race heats, and 4) athletes glycolytic demands are greater than those predicted by perceived exertion or heart rate data alone. These results suggest that snowboard athletes may benefit from supplemental endurance training similar to the physiological demands reported, strategies which can promote active recovery between race heats, and nutrition/supplementation strategies that can preserve glycogen availability throughout the competition. The present study also highlights the need for additional research related to the role that restricted breathing and dynamic core stability plays in snowboard cross performance and possible benefits of hypoxic and/or core strengthening programs.