The Australian Institute of Sport is recognized worldwide for developing elite athletes, largely due to their research and innovation in sports science. So when graduate student Sam Leyh received an opportunity to work with the distinguished AIS, her choice was clear.
Leyh arrived at the Institute in mid-April, literally just weeks after learning she was offered a position. She immediately began helping the team with research, specifically performing studies on the importance of dietary carbohydrates in professional athletes.
Along with a team of two Ph.D. students and an AIS lead, Leyh worked with a group of 11 professional triathletes (several being former Olympians). The athletes maintained their current physical training, but the research team manipulated their diet using a technique known as “train high, train low”. The athletes were split into two groups – one would be training high for a week, while the other group would train low. Going into week two, the groups would then switch.
Both “train high” and “train low” groups ate the exact same amount of carbohydrates during each trial but the differences were when they were consumed. So, if they were in the “train high” group they were allowed to eat normally throughout the day with no time restrictions. However, when they were required to “train low” they were required to eat all of their carbs before they began a late afternoon high-intensity aerobic session (HIT training) and could not consume carbs again until after the following morning’s aerobic session.
“The goal of high-intensity training is to deplete glycogen,” says Leyh. “Current nutrition protocol is to immediately start refueling after training with carbohydrates (and protein) to refuel glycogen and thus begin the recovery process.” Previous research had suggested that withholding carbs overnight may enhance the physiological adaptations. Leyh and her fellow researchers were working toward proving that hypotheses.
The group of athletes were split into two groups and participated in back-to-back 6 day interventions, starting with a performance trial. During the first 6 day period, one group they trained low while the other group trained high. At the end of the first intervention, all athletes went through another performance trial. For the second 6 days period, groups switched so the athletes who previously trained high were now to train low (and those who previously trained low were now to train high). Once the second 6 days were over, the testing ended with a final performance trial.
Throughout the two weeks, the research group continuously collected samples to measure bone breakdown and iron metabolism. “The purpose of the study is to see that even though certain changes may be better for performance it could be causing negative effects in other areas,” Leyh remarked.
As much as we would enjoy knowing the results of their research, the study was large and will be some time before its published.
Leyh’s opportunities at AIS also meant the chance to work alongside key players in the industry, including one of today’s top sports nutrition researchers Dr. Louise Burke (with nearly 300 peer-reviewed publications). Burke has been head of the sports nutrition program at the Australian Institute of Sport for the 27 years and has over 35 years of experience as a sports dietitian. Greg Cox, senior sports dietitian, also worked with Leyh’s team on the research project. Cox is the head nutritionist for Australian Canoeing and Triathlon Australian.
More About Sam:
Sam has a B.S. in Dietetics from the University of Rhode Island and is currently a second year M.S. thesis student focusing on sports nutrition. She’s in Dr. Mike Ormsbee’s laboratory, studying pre-sleep feeding’s impact on metabolism in fit women. Ormsbee, long-time colleagues with Dr. Louise Burke, was able to facilitate Sam’s internship with AIS.
For Leyh, the experience she had is priceless but this soon-to-be graduate isn’t done yet. Before she finishes her master’s degree in December, Sam will be an intern in Phoenix, AZ with EXOS, a leading human performance company.