Impact of Creatine Supplementation on Repeated Sprint Performance in Normobaric Hypoxia
Faculty Advisor Name
Dr. Nick Luden
Department
Department of Kinesiology
Description
Nutritional supplementation is common practice for athletes as they strive for optimal performance and creatine is one of the best known and studied ergogenic supplements on the market. Creatine is a naturally occurring molecule in our body that is primarily responsible for providing a rapid source of energy. During a bout of high intensity exercise, like a 30 second sprint, we rely on anaerobic metabolism, an energy system that does not require oxygen. Within anaerobic metabolism is our creatine phosphate system which provides and replenishes energy in the form of Adenosine Triphosphate (ATP). Skeletal muscle levels of creatine phosphate are diminished during sprint exercise and require about 3 minutes of passive recovery to fully replenish. Thus, when consecutive sprints are separated by insufficient recovery intervals, each sprint is associated with progressively lower starting levels of creatine phosphate, which contributes to worsening sprint performance in each successive sprint. Creatine supplementation is a widely used and well-documented strategy to elevate creatine phosphate levels. Not only does this lead to an increase in the creatine phosphate reservoir at the onset of exercise, it also increases the rate of creatine phosphate replenishment following heavy exercise. As a result, creatine supplementation has been shown to enhance repeated sprint performance.
It is well established in the literature the ergogenic benefits of creatine supplementation, however there is a significant lack of research on the effects of creatine supplementation and high altitude. There is a linear reduction in oxygen content with increasing elevations above sea level which has a profound impact on human physiology and performance. Exercise at and above moderate altitudes (>5,000 feet) when less oxygen is available increases the reliance on anaerobic metabolism. This shift causes a reduction in the replenishment of creatine phosphate, thereby impairing repeated sprint performance. Given the value of creatine supplementation for performance at sea-level/low-altitude (i.e. normoxia), it stands to reason that creatine supplementation would benefit repeat sprint performance in hypoxic conditions.
To test our hypothesis, we will be recruiting a minimum of 20 subjects to perform five exercise testing sessions in the Human Performance Laboratory (Godwin Hall) at James Madison University, spanning about 14 days. The visits will include a preliminary testing visit, two pre-treatment visits (normoxia and hypoxia) and two post-treatment visits (normoxia and hypoxia), with the pre- and post-treatment visits separated by 6 days of either placebo or creatine supplementation. For the normoxia session, participants will breathe in room air from the Human Performance Laboratory (~1300 feet), whereas for hypoxia, participants will breathe from a hypoxic chamber simulating an altitude of 10,000 feet (similar to Leadville, Colorado). The treatment phase will begin the day after Visit 3. Participants will ingest creatine or maltodextrin (placebo) at a dose of 0.3 g of creatine monohydrate per kg of bodyweight for 6 consecutive days.
The aim of this study is to determine the effect of creatine supplementation on sprint performance in both hypoxia and normoxia.
Impact of Creatine Supplementation on Repeated Sprint Performance in Normobaric Hypoxia
Nutritional supplementation is common practice for athletes as they strive for optimal performance and creatine is one of the best known and studied ergogenic supplements on the market. Creatine is a naturally occurring molecule in our body that is primarily responsible for providing a rapid source of energy. During a bout of high intensity exercise, like a 30 second sprint, we rely on anaerobic metabolism, an energy system that does not require oxygen. Within anaerobic metabolism is our creatine phosphate system which provides and replenishes energy in the form of Adenosine Triphosphate (ATP). Skeletal muscle levels of creatine phosphate are diminished during sprint exercise and require about 3 minutes of passive recovery to fully replenish. Thus, when consecutive sprints are separated by insufficient recovery intervals, each sprint is associated with progressively lower starting levels of creatine phosphate, which contributes to worsening sprint performance in each successive sprint. Creatine supplementation is a widely used and well-documented strategy to elevate creatine phosphate levels. Not only does this lead to an increase in the creatine phosphate reservoir at the onset of exercise, it also increases the rate of creatine phosphate replenishment following heavy exercise. As a result, creatine supplementation has been shown to enhance repeated sprint performance.
It is well established in the literature the ergogenic benefits of creatine supplementation, however there is a significant lack of research on the effects of creatine supplementation and high altitude. There is a linear reduction in oxygen content with increasing elevations above sea level which has a profound impact on human physiology and performance. Exercise at and above moderate altitudes (>5,000 feet) when less oxygen is available increases the reliance on anaerobic metabolism. This shift causes a reduction in the replenishment of creatine phosphate, thereby impairing repeated sprint performance. Given the value of creatine supplementation for performance at sea-level/low-altitude (i.e. normoxia), it stands to reason that creatine supplementation would benefit repeat sprint performance in hypoxic conditions.
To test our hypothesis, we will be recruiting a minimum of 20 subjects to perform five exercise testing sessions in the Human Performance Laboratory (Godwin Hall) at James Madison University, spanning about 14 days. The visits will include a preliminary testing visit, two pre-treatment visits (normoxia and hypoxia) and two post-treatment visits (normoxia and hypoxia), with the pre- and post-treatment visits separated by 6 days of either placebo or creatine supplementation. For the normoxia session, participants will breathe in room air from the Human Performance Laboratory (~1300 feet), whereas for hypoxia, participants will breathe from a hypoxic chamber simulating an altitude of 10,000 feet (similar to Leadville, Colorado). The treatment phase will begin the day after Visit 3. Participants will ingest creatine or maltodextrin (placebo) at a dose of 0.3 g of creatine monohydrate per kg of bodyweight for 6 consecutive days.
The aim of this study is to determine the effect of creatine supplementation on sprint performance in both hypoxia and normoxia.
