For years, health experts have touted the benefits of regular exercise for managing blood sugar. However, emerging research is focusing on when you exercise and how that impacts your body’s ability to regulate glucose levels. Recent studies suggest that working out in the afternoon or evening may be more beneficial for blood sugar control compared to morning workouts. This is particularly relevant for individuals with insulin resistance, overweight or obesity, and those managing type 2 diabetes.
The Science Behind Exercise and Blood Sugar
Physical activity plays a crucial role in regulating blood sugar because it increases insulin sensitivity. This means that your cells are better able to use available insulin to take up glucose, both during and after exercise. When muscles contract during exercise, they can take up glucose and use it for energy, regardless of whether insulin is available. This process helps lower blood sugar levels, improving insulin sensitivity and increasing glucose absorption by cells, even after the workout is completed.
Regular exercise also enhances cardiovascular health, which is closely linked to better blood sugar control. The American Diabetes Association notes that physical activity can lower blood glucose for up to 24 hours or more after a workout.
Why Evening Exercise Might Be More Effective
Several studies have shown that exercising later in the day could lead to better blood sugar management. A study published in the journal Obesity found an association between being most active later in the day and having more stable blood sugar levels over a 24-hour period. Specifically, participants who completed their moderate-to-vigorous physical activity during the evening had lower average glucose readings compared to inactive participants.
Another study, published in Diabetologia, revealed that participants who exercised in the afternoon experienced an 18% reduction in insulin resistance, while those who worked out in the evening saw a 25% decrease. This study also noted that morning exercise or spreading activity throughout the day did not show significant improvements in insulin resistance or liver fat content.
Researchers from the University of Granada also monitored a group of people and found that physical activity in the evening may be more beneficial for achieving stable blood sugar levels. They discovered an association between completing activity in the evening and lower blood glucose levels.
Breaking Down the Benefits:
- Improved Insulin Sensitivity: Evening exercise appears to enhance insulin sensitivity more effectively than morning exercise, allowing cells to use glucose more efficiently.
- Reduced Insulin Resistance: Studies indicate that afternoon and evening workouts lead to significant reductions in insulin resistance, a key factor in type 2 diabetes.
- More Stable Blood Sugar: Being active later in the day is linked to more stable blood sugar levels throughout the day and overnight.
- Lower Glucose Levels: Evening exercise has been associated with lower average glucose readings compared to periods of inactivity.
Morning Exercise Still Holds Value
While the research leans towards afternoon and evening exercise for optimal blood sugar control, morning exercise still offers substantial benefits. For those who find it challenging to maintain a consistent workout routine, morning exercise might be the best option. Some studies indicate that morning exercise, particularly in a fasted state, may be beneficial for overall 24-hour glucose levels in individuals with type 2 diabetes. Additionally, morning workouts are associated with improved overall physical activity adherence and lower daily caloric intake in individuals with obesity.
However, for individuals with type 1 diabetes, it is important to note that late-day exercise can promote a greater drop in glucose during exercise compared with fasted morning exercise and increases the risk for nocturnal hypoglycemia.
Exercise After Meals: A Powerful Strategy
In addition to the timing of exercise, research also suggests that exercising after meals can be beneficial for managing blood sugar spikes. A 2023 study demonstrated that even a short walk or light activity after meals can significantly reduce post-meal sugar spikes. This is particularly useful for people with diabetes or those prone to blood sugar fluctuations after eating. It has been suggested that those without diabetes should start moving 15 minutes after eating, while those with diabetes should move 30 minutes after eating to better manage blood sugar levels.
The “Dawn Phenomenon” and Exercise Timing
It’s worth noting that the “dawn phenomenon,” a natural rise in blood glucose that occurs between about 4:00 and 8:00 a.m., can result in higher levels during morning exercise. For this reason, consider moving your workout to later in the day if you usually exercise in the early mornings, as the same workout done later in the day is less likely to result in a rise.
Types of Exercise for Blood Sugar Control
To maximize the benefits of exercise for blood sugar regulation, it helps to incorporate a variety of activities. Here are some types of exercise to consider:
- Aerobic Exercise: Activities like walking, swimming, cycling, and running improve heart health and lower blood sugar.
- Strength Training: Lifting weights or using resistance bands helps build muscle mass, which increases glucose uptake by cells and improves insulin sensitivity.
- Yoga and Stretching: Yoga can help reduce stress and promote relaxation, which can help lower cortisol and balance blood sugar levels.
The Centers for Disease Control and Prevention (CDC) recommends that healthy adults aim for 150 to 300 minutes of moderate-intensity or 75 to 150 minutes of vigorous-intensity physical activity each week. However, even small amounts of physical activity can make a difference.
Important Considerations
While timing and type of exercise are important, consistency is key. The most crucial aspect is to find a time that works for you and stick to a routine. Here are a few other factors to keep in mind:
- Individual Responses: Everyone’s body responds to exercise differently. Monitoring your blood sugar levels before, during, and after exercise can help you understand how your body reacts to different activities and timing.
- Medication: If you are on diabetes medication, consult your doctor to avoid the risk of low blood sugar (hypoglycemia). Adjustments to medication or meal timing may be necessary depending on your exercise schedule.
- Diet: Be mindful of your diet and avoid excessive carbohydrate intake before and during workouts, which can contribute to a glucose rise. Consider snacks with slower-acting carbohydrates, like yogurt with nuts or peanut butter.
- Listen to Your Body: Start slow, gradually increase your activity level, and ensure you stay hydrated.
The Takeaway
Emerging research suggests that exercising in the afternoon or evening may offer the most significant benefits for blood sugar control due to improved insulin sensitivity and reduced insulin resistance. However, it’s important to remember that physical activity at any time of day is beneficial. The key is to find a routine that works for you and stick to it, while also considering the timing of your workouts in relation to your meals. Whether you choose to exercise in the morning, afternoon, or evening, regular physical activity, combined with a healthy diet, is crucial for maintaining healthy blood sugar levels and overall well-being.
