When you exercise, your body turns glucose, or sugar, into energy to keep you going. Even conditioned athletes may sometimes feel the effects of blood sugar depletion brought on by vigorous exercise. However, if you have diabetes or other disorders of serum glucose regulation, exercise can be a challenge, as it can make maintaining a healthy blood glucose level particularly difficult. Your trip to the gym requires planning, as well as an understanding of symptoms of and interventions for exercise-induced hypoglycemia, or low blood sugar.
Physical Activity and Hypoglycemia
Vigorous and/or endurance exercise requires sustained energy. For your body, this energy is glucose, or sugar, broken down from the foods you eat every day. For regular daily activities, your body relies on the glucose readily available in your blood. However, your liver and muscles also keep a store of glucose, in the form of glycogen, as a backup for when blood stores of energy run dry. At the beginning of your workout, your body burns glucose from your blood first for energy before using glycogen stores in your muscles and liver. Your blood glucose can fall too low, a condition called hypoglycemia, as your body uses it to sustain increased activity during exercise. This is particularly true if your blood sugar is unstable due to an underlying medical disorder, such as diabetes, and its treatment.
Symptoms of Low Blood Sugar
Hypoglycemia symptoms vary by individual. You may notice symptoms quickly after your serum glucose dips too low. Other individuals may not notice symptoms until hypoglycemia becomes profound. Common early symptoms include confusion, lightheadedness, fatigue and sleepiness. You may notice that you are perspiring more than usual, and you may feel anxious, nervous and shaky. You may also feel hungry despite having eaten recently. If ignored, early symptoms of hypoglycemia can lead to rapid physical and mental decline. In later stages of glucose depletion, those around you may question your behavior and condition. You may have difficulty seeing due to visual disturbances. You may lose consciousness, after which time you may experience seizures or fall into a coma. Loss of consciousness caused by hypoglycemia is a medical emergency, because you are no longer able to intervene on your own behalf. As your blood sugar continues to fall, you are at risk of severe health consequences and even death.
Timely Interventions
Timely hypoglycemia interventions are critical to avoid. You don't want to become so incapacitated that you cannot take care of yourself and your condition. Using a glucometer, measure your blood glucose before your workout. If it is less than 100 mg/dL, take time to eat a healthy snack before beginning. Ideal snacks to prevent hypoglycemia are those containing at least 15 g carbohydrate. Add 7 to 8 g protein to the snack if it will be awhile before you eat again. This will help your body maintain blood sugar levels longer than just carbohydrate consumption alone. Listen closely to your body during exercise. Take a break from your workout immediately upon noticing hypoglycemia symptoms. While you are resting, measure your blood glucose. You are at risk for developing hypoglycemia for up to 24 hours after vigorous exercise, as your body can take this long to rebuild its glucose reserves. It is important that you monitor your glucose levels closely right after working out and for 24 hours thereafter.
Further Considerations
If you have a history of exercise-induced hypoglycemia, you may want to consider asking a friend or family member to exercise with you. Being alone during an episode of hypoglycemia resulting in unconsciousness places your life at risk. Teach somebody you trust to recognize the signs of low blood sugar, as well as how to intervene for you should it become necessary. And always wear medical identification alerting those around you of your condition. And finally, if you have diabetes, comply with all doctor recommendations regarding treatment. The goal of diabetes therapy is to lower your blood glucose to a manageable, healthy level. Your doctor will likely warn you to avoid such interventions, such as medications or insulin injections, before strenuous or stressful activities to help prevent hypoglycemia.
