A phenomenon that was virtually impossible just a couple of decades ago is now becoming increasingly commonplace: Athletes with type 1 diabetes are not only competing at elite levels in just about every sport, but in many cases are actually beating nondiabetic competitors. Gary Hall Jr. won three Olympic Gold medals in swimming after his diagnosis in 1999. Natalie Strand, an anesthesiologist, won the TV extreme-sport reality show Amazing Race with her partner last December. And bicycle racers Team Type 1 won the Race Across America in 2009 and 2010.

Of course, exercise is encouraged for people with both type 1 and type 2 diabetes as a way of improving glycemic control, cardiovascular health, and quality of life. But in competitive sports, milliseconds count and physical perturbations of any kind can mean the difference between winning and losing. With type 1 diabetes, aerobic exercise can result in hypoglycemia, while anaerobic exercise can cause glucose levels to rise. Many sports involve a combination of the two. The athlete with type 1 diabetes must perform frequent glucose checks and eat or take insulin as needed to maintain normal or near-normal glucose, while at the same time performing the athletic feat itself. It seems nearly impossible, yet they do it … with the help of both new technology and devoted health care professionals.

Javier Megias of Team Type 1 checks his blood sugar while warming up for a time trial at a race in Italy.

“I take each athlete, learn their sport and find solutions,” said Dr. Anne Peters, the endocrinologist who managed Gary Hall Jr.’s diabetes regimen during the Olympics and is now doing the same for professional racecar driver Charlie Kimball. “Each athlete is unique and requires individualized care.”

New research is aimed at understanding the physiology of these athletes better in order to improve that care. Team Type 1, sponsored by Sanofi, is funding a study in which data are being collected on about 10 bike racers with and 10 without type 1 diabetes. The athletes are being evaluated before, during, and after races using continuous glucose monitors and devices placed on the bicycles that measure variables such as power, heart rate, energy expenditure, speed, and altitude. Data on the athletes’ diet, insulin doses, and other variables are also being collected in a total of five major cycling events, each of which includes 4-8 individual races. “Bottom line, it’s a lot of data,” said Team Type 1 director of research Dr. Juan Frias.

Interestingly, blood glucose values of up to 200 mg/dL - far above “normal” – have been recorded in the nondiabetic riders during very intense portions of races. This “stress hormone” effect had been seen previously in the lab and in some hospitalized patients, but has not been well documented in field-based, real-world studies of healthy people. “Ultimately we hope that this feasibility study will provide data that will help us begin to better understand the optimal glucose concentrations needed to maximize athletic performance, Dr. Frias said.

Findings from the TT1 study will likely be announced at scientific conferences during 2012 and ultimately published, he told me.

Another research project, led by Nate Heintzman, Ph.D., of the University of California, San Diego, is studying athletes who are part of Insulindependence, an organization that promotes physical fitness and sport for people with type 1 diabetes. One of Insulindependence’s recreation-specific clubs, Triabetes, trains people with type diabetes to compete in triathalons. The UCSD-supported project, called the Diabetes Management Integrated Technology Research Initiative (DMITRI), is looking at many of the same variables as in the TT1 study, but is also collecting other data, including behavioral and cognitive information and biospecimens for DNA sequencing.

Insulindependence Captains starting their track workout at UCSD in June. Every person in this photo has type 1 diabetes.

“The idea is to use emerging wireless and device technology as well as genetics and genomics to understand more about the personalized basis of blood glucose management. I think we’ll uncover trends to help tailor therapeutic regimens, and also develop technology on a personal level,” Dr. Heintzman said.

The DMITRI project began in June, and data will begin to emerge in the coming months. In the meantime, if you’re a health care provider or person with diabetes interested in learning more, Dr. Peters recommends Sheri Colberg-Ochs Ph.D.’s Diabetic Athlete’s Handbook. And if you’re seeking inspiration, you can follow Team Type 1 founder and CEO Phil Southerland’s efforts to enter the team in the 2012 Tour de France, professional cycling’s most elite event.

Bottom line, according to Dr. Peters, “The truly gifted athletes I have known seem to be born with an ability that compels them to compete, diabetes or not.”

-Miriam E. Tucker (@MiriamETucker on Twitter)

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