Why exercise is good for blood sugar

Not too long ago, a reader reached out to me with a question about the connection between exercise and blood sugar. While it's common knowledge that physical activity is often recommended to prevent or manage type 2 diabetes, it's not widely known how movement can be a powerful tool, especially for those with mildly elevated blood sugar.

The rationale for recommending physical activity is twofold. Firstly, exercise plays an important role in preventing or managing diabetes and secondly, it significantly reduces the risk of heart disease. This last point is especially important because diabetes inherently increases the risk of heart disease.

Now, let's get to the "why." Exercise contributes to lowering blood sugar levels by increasing the body's sensitivity to insulin, the hormone responsible for enabling cells to use blood sugar for energy. Consider insulin as a key that opens cellular doors, permitting the entry of glucose. If your body lacks enough insulin, the keys are insufficient, and some diabetics may need insulin supplements. On the other hand, if your body becomes "insulin resistant," insulin struggles to open cellular doors. A key is struggling to fit into a rusty lock and after a walk, the key slides smoothly in and unlocks the door.

Physical activity can effectively lower blood sugar levels for 24 hours or more by increasing the sensitivity of your cells to insulin produced by the pancreas. Even for those with insufficient insulin production, muscle contraction during activity enables muscle cells to absorb glucose from the bloodstream. In general, greater muscle mass increases insulin sensitivity.

Addressing the heart disease link, prolonged high blood sugar can damage blood vessels and nerves critical to heart function. Damaged vessels become stiff, contributing to high blood pressure. Diabetes can also damage the kidneys, causing water and sodium retention, further increasing blood pressure.

Regardless of your blood sugar levels, a single exercise session can lower blood pressure for about 24 hours, while regular, regular exercise provides a more long-lasting blood pressure-lowering effect. It also improves cholesterol and triglyceride levels. Despite understanding these benefits, barriers such as time, cost, energy, perceived difficulty and lack of enjoyment often prevent people from engaging in physical activity.

The recommended amount of activity for healthy blood sugar and blood pressure levels aligns with general health guidelines: at least 150 minutes per week of moderate-intensity aerobic activity, such as brisk walking, and two full-body resistance training sessions per week. Although both resistance training and aerobic exercise increase insulin sensitivity, a combination of the two proves more beneficial.

Resistance training can include free weights, weight machines, resistance bands, or using your body weight (eg, pushups). Meeting aerobic activity recommendations may require a daily 20- to 25-minute walk or break it up into smaller segments. Notably, any period of moderate to vigorous physical activity contributes to meeting the core guidelines.

For people with type 2 diabetes, research suggests that walking for 15 minutes after a meal and periodically moving every half hour after sitting can improve blood sugar levels. To increase your activity, consider choosing an enjoyable exercise, starting small and progressing, setting specific goals, scheduling activities, and perhaps incorporating accountability by sharing goals with friends or family.

An important reminder: If you have diabetes and are not currently exercising, consult your doctor or diabetes educator. Special considerations regarding hydration, blood sugar monitoring, and foot care must be taken into account.