An A1C test measures your average blood sugar level over the preceding two to three months, reflecting how well glucose has been managed over that period. This metric, formally known as glycated hemoglobin, indicates the percentage of hemoglobin proteins in the blood that have sugar molecules attached. Physical activity is a potent, non-pharmacological tool that can significantly influence this long-term blood sugar average. Consistent movement helps the body process glucose more effectively, which ultimately lowers the A1C percentage.
How Exercise Improves Insulin Sensitivity
Exercise improves the body’s ability to utilize glucose through two distinct physiological processes. The first is an immediate effect that occurs during and directly after a workout. Muscle contraction allows glucose to be taken up into muscle cells without needing insulin, a process known as insulin-independent glucose uptake. This mechanism directly reduces the amount of circulating sugar in the blood immediately following activity.
The second effect is a long-term improvement in overall insulin sensitivity. Regular physical activity enhances the responsiveness of cells to insulin, meaning the body needs to produce less of the hormone to move glucose into cells for energy. This improved sensitivity can last for up to 72 hours following an exercise session. Over time, this consistent cellular responsiveness leads to lower average blood sugar levels, reflected in a reduced A1C reading.
Expected A1C Reduction Ranges
Consistent exercise can reduce A1C levels by a range comparable to some oral diabetes medications. For individuals with type 2 diabetes, combining aerobic and resistance training can lower the A1C value by 0.5% to 1.0% or more. The magnitude of this reduction is often greater for those starting with a higher baseline A1C.
Aerobic exercise, such as brisk walking or cycling, improves glycemic control by promoting better blood flow and glucose uptake in muscle cells. Resistance training, which involves activities like lifting weights or using resistance bands, also plays a role by building muscle mass. Since muscle tissue is the primary site for glucose storage and use, increasing muscle mass provides more tissue capable of absorbing glucose from the bloodstream.
Studies have indicated that while both aerobic and resistance training independently reduce A1C, the combination of both types yields superior results for overall glycemic control. Resistance training alone has been shown to improve A1C by about 0.57%, while aerobic training may lead to a slightly greater reduction. The most effective strategy involves combining these two modalities to maximize immediate glucose utilization and long-term insulin sensitivity improvements.
Designing an Effective Exercise Routine
To achieve the most significant A1C reduction, an exercise routine should strategically combine aerobic activity and resistance training. Current recommendations suggest aiming for a minimum of 150 minutes of moderate-intensity aerobic exercise per week. Moderate intensity means you are working hard enough to raise your heart rate and break a sweat, but you can still carry on a conversation.
This aerobic goal can be met through activities like brisk walking, jogging, swimming, or dancing, ideally spread out over five days per week. In addition to aerobic activity, two to three sessions of resistance training per week are recommended, targeting all major muscle groups. Resistance exercises can include bodyweight movements like squats and push-ups, or using weights and resistance bands.
It is beneficial to incorporate short bouts of activity throughout the day, such as a 10-to-15-minute walk after meals, which can significantly reduce post-meal blood sugar spikes. Consistency is more impactful than occasional high-intensity efforts, so finding enjoyable and sustainable activities is important for improving metabolic health and lowering A1C.
Essential Safety Considerations for Physical Activity
Individuals managing blood sugar should consult with a healthcare provider before beginning any new exercise program. This consultation ensures the plan is appropriate given any existing health complications and current medications. A medical professional can help tailor the exercise prescription and recommend necessary adjustments to medication or insulin doses.
Monitoring blood sugar levels is a necessary precaution, particularly before and after exercise, to understand how the body responds to different activities and intensities. If blood sugar is below 100 mg/dL before a workout, a small carbohydrate snack may be needed to prevent hypoglycemia. It is also important to keep a source of fast-acting carbohydrates, such as glucose tablets or juice, readily available during activity in case of an unexpected drop in blood sugar. Proper hydration is also important, as is wearing appropriate, well-fitting footwear to protect the feet, especially for those with nerve damage.