Diabetes and Sports Performance: Managing Health for Optimal Athletic Success

November, is American Diabetes Month. Roughly over 38 million americans live with diabetes, about 8 million of those individuals are undiagnosed.Diabetes is more than a medical condition—it’s a metabolic challenge that can directly influence energy levels, recovery, and athletic performance. For athletes and active individuals, understanding how the body uses glucose and insulin is essential for staying healthy, performing efficiently, and preventing complications during training or competition.

Many elite athletes—from marathon runners to professional football players—compete successfully with diabetes. Their success emphasizes that with structure, monitoring, and discipline, diabetes doesn’t have to limit potential. Instead, it demands precision—the same quality that defines great athletes.

What Is Diabetes?

Diabetes Mellitus (AKA Diabietes) is a metabolic disorder where the body struggles to regulate blood glucose (sugar) due to issues with insulin, the hormone responsible for moving glucose from the bloodstream into muscle and body cells for energy. Blood glucose (sugar) levels can become abnormally high because the pancreas does not produce enough insulin or because the body’s cells don’t respond properly to the insulin that’s made.  When blood glucose levels are too high (hyperglycemia) or too low (hypoglycemia), symptoms such as polydipsia (excessive thirst), fatigue, or amblyopia (blurred vision) may occur. If glucose remains unavailable to the cells, the body may start breaking down fats for energy, producing ketones — acids that can become harmful in excess.

Maintaining stable glucose levels is critical—not only for long-term health but also for consistent energy output, endurance, and recovery. Below are some guidelines regarding blood glucose levels:

·      Normal blood glucose: 80–100 mg/dL

·      Pre-diabetic: 101–125 mg/dL

·      Diabetes: 126 mg/dL or higher

How Diabetes Affects Athletes

Athletes with diabetes can absolutely perform at elite levels, but they must pay closer attention to how nutrition, activity, and blood sugar regulation interact. Both hyperglycemia and hypoglycemia can negatively impact performance.

• Hypoglycemia may cause dizziness, fatigue, or confusion during workouts.

• Hyperglycemia can lead to dehydration, slower recovery, and reduced muscle efficiency.

Types of Diabetes in Athletes

Type 1 Diabetes

An autoimmune condition where the pancreas produces little to no insulin. Type 1 athletes depend on insulin therapy and careful monitoring to regulate blood glucose levels.

Key Facts:- Usually develops in childhood or adolescence - Cause is unknown but may involve genetics and environmental triggers  - Requires daily insulin for glucose regulation Common Symptoms:- Frequent urination  - Excessive thirst (polydipsia)  - Increased appetite  - Fatigue  - Blurred vision  - Unexplained weight loss  - Slow-healing wounds  Risk Factors: Family history of Type 1 diabetes Performance Tip: Pre- and post-workout glucose monitoring is essential. Insulin timing, carbohydrate intake, and hydration must align with training demands to avoid sudden energy drops.

Type 2 Diabetes

Type 2 diabetes occurs when the body becomes resistant to insulin, causing the pancreas to overwork to maintain normal glucose levels. Over time, the pancreas can’t keep up, leading to elevated blood sugar.

This type is commonly influenced by lifestyle factors such as poor diet, inactivity, excess weight, or even familial history—but with consistent physical activity, Type 2 diabetes can be managed and even improved.

Symptoms are like Type 1 but may also include numbness or tingling (neuropathy) in the hands and feet.  Performance Tip: Regular exercise enhances insulin sensitivity, meaning muscles can use glucose more effectively. Resistance training and aerobic workouts both play key roles in improving blood sugar control.

Gestational Diabetes

Develops during pregnancy and typically resolves after childbirth but may increase future risk of Type 2 diabetes. Postpartum activity and nutrition programs can help reduce that.

Former NBA player Gary Forbes

Former US Olympian Kori Carter

Former Olympian Alysia Montano

Performance and Recovery Complications

Uncontrolled diabetes can affect systems crucial to athletic health and longevity:

• Cardiovascular System: Increases the risk of heart disease and hypertension, both of which reduce endurance and stamina. Also elevates the risk of stroke.

• Musculoskeletal Health: Impaired circulation and nerve function (neuropathy) can delay recovery, hinder muscle repair, and increase the risk of injury.

• Vision & Coordination: Conditions such as retinopathy and blurred vision (amblyopia) may affect balance, depth perception, and reaction time.

• Skin & Feet: Reduced sensation and poor circulation elevate the risk of blisters, infections, and delayed wound healing—common concerns for active individuals.

• Dehydration & Electrolyte Imbalance: Elevated blood glucose levels can cause increased urination and fluid loss, leading to dehydration and reduced performance capacity. Prolonged imbalance may contribute to chronic kidney disease.

• Diabetic Ketoacidosis- A life-threatening complication most often seen in Type 1 diabetes. It occurs when the body produces too many ketones, leading to metabolic acidosis.  Warning Signs of DKA:

  • Hyperglycemia 

  • Nausea or vomiting 

  • Confusion

  • Fruity-smelling breath 

  • Rapid breathing 

Monitoring and Managing Diabetes in Training

Essential Tools

• Self-Monitoring Blood Glucose (SMBG): Finger-prick testing before and after workouts

• Continuous Glucose Monitoring (CGM): Wearable sensors that track levels throughout the day

• A1C Tests: Show average glucose over several months—important for long-term health tracking

Finger Prick Test

Continuous Glucose Monitor

Athlete Management Plan

1. Fuel Smart: Balance carbohydrates, lean protein, and healthy fats. Time carb intake around workouts to maintain steady energy and prevent hypoglycemia. Limit processed foods, refined sugars, and unhealthy fats. Opt for whole grains, lean proteins, fruits, and vegetables. 

2. Train Consistently: Aim for at least 30 minutes of activity daily. Exercise increases insulin efficiency and supports cardiovascular health.

3. Hydrate Well: Diabetes increases dehydration risk. Maintain fluids before, during, and after training.

4. Prioritize Recovery: Stable glucose helps muscles repair efficiently post-training. Poor control can delay healing and increase soreness.

Work With Your Team: Collaboration between athletic trainers, physicians, and dietitians ensures proper glucose management strategies during practices and games.

Final Thoughts

Managing diabetes while training or competing requires dedication and knowledge, but it’s entirely possible to reach high levels of athletic performance. By combining medicalmanagement, nutrition, and sports recovery strategies, athletes can maintain strong blood glucose control, reduce complications, and perform at their best—safely and sustainably.

At its core, diabetes management in sports is about balance—balancing fuel, effort, and recovery to keep the body performing in peak condition.