Alexander Zverev was seen administering an insulin injection during the Wimbledon men's singles final on Sunday, drawing attention to the daily reality of competing at the highest level while managing Type 1 diabetes.
The German tennis star, who faced world No. 1 Jannik Sinner in his first Wimbledon final, injected insulin into his leg during a changeover after taking a medical pouch from his courtside bag.
Zverev was diagnosed with Type 1 diabetes at age 4 and has long been open about using insulin therapy to regulate his blood sugar on and off the court. Because of his condition, he is also granted a medical exemption that allows him to check his phone during matches to monitor his continuous glucose monitor (CGM), avoiding repeated finger-prick blood tests.
The exemption complies with Grand Slam medical protocols for players with diabetes, allowing them to monitor glucose levels and administer insulin when medically necessary during competition.
Zverev has previously spoken about the challenges of managing blood sugar during elite competition. During the Halle Open in June, a malfunctioning glucose sensor displayed falsely high readings, leading him to inject more insulin than needed. He later said he had to consume about 350 grams of sugar during the match after his blood glucose dropped unexpectedly.
His visible insulin injection during the Wimbledon final has highlighted how advances in diabetes technology have enabled many athletes with Type 1 diabetes to safely compete at the highest levels of sport.
What Is Type 1 Diabetes?
Type 1 diabetes is an autoimmune disease in which the body's immune system mistakenly attacks the insulin-producing beta cells in the pancreas. As a result, the body produces little or no insulin, the hormone that moves glucose from the bloodstream into cells for energy.
People with Type 1 diabetes require lifelong insulin therapy to survive. Unlike Type 2 diabetes, Type 1 diabetes is not caused by lifestyle factors and cannot be prevented.
Why Exercise Makes Blood Sugar Harder to Predict
For athletes, managing Type 1 diabetes becomes even more complicated during intense physical activity.
Exercise can cause blood glucose levels to either fall or rise, depending on the intensity, duration, and timing of activity. Endurance exercise often lowers blood sugar by increasing glucose uptake by muscles, while high-intensity competition can temporarily raise blood sugar because stress hormones such as adrenaline stimulate the liver to release stored glucose.
Athletes often need to adjust insulin doses, carbohydrate intake, and hydration before, during, and after competition to avoid dangerous highs or lows.
How CGMs and Insulin Pens Help Athletes Compete
Technological advances have transformed diabetes management for elite athletes.
Continuous glucose monitors use a tiny sensor placed under the skin to measure glucose levels throughout the day, sending real-time readings and alerts to a smartphone or compatible receiver. This allows athletes to detect rapid changes without repeatedly stopping for finger-stick tests.
Insulin pens, like the one Zverev used during the Wimbledon final, enable precise insulin dosing within seconds, making it easier to respond quickly to changing glucose levels during competition.
Together, these tools help athletes make informed decisions about insulin, nutrition and performance while reducing the risk of severe hypoglycemia or hyperglycemia.
Proof That Type 1 Diabetes Doesn't Have to Limit Performance
Although managing Type 1 diabetes requires constant planning, experts emphasize that the condition does not prevent people from excelling in sports.
With individualized treatment plans, modern glucose-monitoring technology and access to insulin, athletes can safely train and compete at the highest levels.
Zverev's courtside insulin injection served as a visible reminder that managing a chronic condition is simply part of his routine—one that allows him to continue competing for Grand Slam titles while living with Type 1 diabetes.
