### How Exercise Impacts Blood Sugar Levels in Diabetes Exercise can have varying effects on blood sugar levels in people with diabetes. Generally, exercise helps to lower blood sugar levels over a 24-hour period. This is because physical activity increases the demand for energy, which is met by using sugar from the bloodstream and stored glucose in muscles and the liver. Over the next 24 hours, the body replenishes these stores by drawing sugar from the blood, leading to a prolonged blood sugar-lowering effect. However, exercise can also cause a temporary spike in blood sugar levels. This is often due to the release of stress hormones like adrenaline during intense workouts, which can increase blood sugar temporarily. Additionally, if there is insufficient insulin in the body, exercise can lead to higher blood sugar levels because the body cannot effectively move sugar into the cells, causing the liver and kidneys to release more glucose into the bloodstream. It's important to monitor blood sugar levels before and after exercise. The Mayo Clinic advises against starting exercise if blood sugar levels are above 250 mg/dL or below 100 mg/dL. High blood sugar levels combined with low insulin can lead to diabetic ketoacidosis (DKA), a serious condition. Conversely, low blood sugar levels can lead to hypoglycemia, especially if insulin levels are high. To manage these risks, it's recommended to test blood sugar frequently, especially when starting a new exercise routine. Eating a snack with 15-30 grams of carbs before exercise can help prevent hypoglycemia. Timing exercise after meals can also be beneficial, as it helps to use the glucose from the meal and improve blood sugar levels for the next 24 hours. In summary, while exercise generally lowers blood sugar levels, it's essential to be aware of the potential for temporary spikes and to manage blood sugar levels carefully to avoid complications.