Exercise Essentials for Type 2 Diabetes

 Diabetes is a lasting health condition that affects how your body transforms food into energy. When you eat, your body breaks down food into various parts, including sugar, also known as glucose. This sugar enters your bloodstream, prompting your pancreas to release insulin, a hormone that acts like a key, allowing cells to use the blood sugar for energy. In diabetes, your body either doesn't produce enough insulin or can't use it effectively, leading to higher levels of sugar stuck in the blood.

Globally, ~ 422 million people have diabetes, with around 38 million in the United States alone. Shockingly, diabetes is the 8th leading cause of death in the USA, and 1 in 5 individuals may not even be aware that they have it. Over the past few decades, both the number of cases and the prevalence of diabetes have been steadily on the rise. Understanding this condition is vital for managing it effectively and ensuring better health outcomes.

Unraveling the Diabetes Puzzle

There are three main types of diabetes: type 1, type 2, and gestational diabetes (which occurs during pregnancy). Today, we will focus on type 2 diabetes (T2D), which occurs when the body's organs resist the effects of insulin, and the pancreas doesn't produce enough insulin. This type makes up 90-95% of diabetes cases and often develops over many years. While it is usually diagnosed in adults, it is increasingly observed in children, teens, and young adults. Effectively managing T2D requires a delicate balance – constantly checking blood sugar levels, adeptly avoiding complications, and providing education to those treading this path. Your doctor is likely to recommend lifestyle adjustments, and one significant aspect is incorporating exercise or physical activity into your routine.

When you move your body, your muscles actively pull sugar from your blood, a process that doesn't depend on whether your body is making insulin or not. The exciting part happens 2-72 hours after you exercise – during this time, your body becomes more responsive to insulin. Research consistently links the intensity and duration of physical activity with better blood sugar control, making regular exercise a key player in managing diabetes and overall health.

Today, we're diving into the latest insights from the American College of Sports Medicine and the American Diabetes Association. They've updated their 2010 stance on exercise and T2D, updating their recommended guidelines for activity.

Exercise Essentials: Breaking down Physical Activity

Exercise comes in three main forms: aerobic, resistance, and combination. Each type engages your muscles and burns energy, but they differ in key aspects like frequency, intensity, type, and timing – collectively known as FITT. Understanding these parameters is crucial, as they shape the specific changes your body experiences.

Aerobic exercise spans longer durations, ranging from several minutes to hours, featuring repetitive, low-resistance activities like running, cycling, or swimming. Conversely, resistance training involves short bursts of high-intensity activity, with powerful muscle contractions performed in a single or a few repetitions. Think weight training or powerlifting. The combined exercise category is diverse, encompassing circuit, high-intensity, and sprint interval training. These activities involve intense muscle contractions for short durations, followed by a recovery period. While these are broad definitions, they set the stage for our exploration of exercise in this article.

Physical Activity Recommendations for Adult Americans

Keeping active is key to a healthy life, and the 2018 Physical Activity Guidelines for All Americans give us practical goals to aim for. Here's a simple breakdown:

• Move More, Sit Less: Avoid sitting for too long and include some movement in your daily routine. Any amount of physical activity is a step in the right direction.
• Aerobic Activity for Health: For good health, aim for 150-300 minutes a week of moderate-intensity activities like brisk walking. Alternatively, you can go for 75-150 minutes of more intense activities or a mix of both. Spread these activities across the week.
• Strength Training: Alongside aerobic exercises, do muscle-strengthening activities at least twice a week. This could include lifting weights or doing exercises that work different muscle groups.
• Extra Benefits with More Activity: Going beyond these guidelines brings even more health benefits. Adding more physical activity to your routine boosts your overall well-being.

Table 1: Key exercise guidelines

Adapted from source.

Check Table 1 for more details. Remember to consult your healthcare provider before starting any new exercise routine, especially if you have existing health conditions. The goal is to make physical activity a regular and enjoyable part of your life!

Table 1: Key exercise guidelines

Adapted from source.

Tailoring Exercise for Adults with T2D

Exercise is a powerful tool for managing T2D and preventing other health issues that often come along. If you're dealing with T2D, teaming up with healthcare or fitness pros is a smart move. They can tailor your exercise plan to keep you safe and help you manage things like blood sugar levels and foot care. It's all about making your health journey smoother and more successful!

For everyone, following the 2018 Physical Activity Guidelines for Americans is like a roadmap to a healthier life. But if you're managing T2D, a few adjustments are key. 

• Aerobic Exercise: All adults with T2D should follow the same recommendations for aerobic exercise, with no more than two consecutive days between exercise bouts, due to the transient nature of exercise-induced improvements in insulin action. It’s been shown that improvements in insulin sensitivity can last anywhere from 2-72 hours after exercise (the decrease in blood sugar levels is very closely associated with physical activity length and intensity). Those with comorbid health conditions and compromised older adults with T2D should try to get as much aerobic activity as their physical and mental health allows. Regular aerobic exercise helps control blood sugar and reduces the A1C number, a crucial measure of long-term blood sugar levels. Even if you don't shed pounds, your body gets healthier in many ways, from improved insulin sensitivity to better cholesterol levels and increased fitness.
• Resistance Training: Adults should also try to meet the current recommendations for resistance training, as hitting the weights is a game-changer for those with T2D. It boosts strength, bone density, and insulin sensitivity. Combining it with moderate weight loss works wonders. Older adults with T2D who embrace resistance training experience a remarkable three-fold drop in their A1C levels. Higher-intensity activity in resistance training has more benefits for overall glucose management and keeping insulin levels in check. For those who may find these recommendations challenging, focusing on enhancing functional fitness and balance becomes key.
• Flexibility: Due to the nature of T2D, the regular limitations to joint mobility with aging are accelerated. Therefore, it's important to incorporate exercises that enhance flexibility into your training program. While stretching exercises increase the range of motion and flexibility, they generally don’t impact glycemia unless undertaken as part of another physical activity, like yoga, or tai chi (for example, yoga improves overall glycemia, lipid levels, and body composition in adults with T2D). Flexibility training is generally low-intensity and easy to perform, so it is a great entry point into a more physically active lifestyle for less fit and older adults. It is recommended that those with T2D do flexibility-based activity two to three days a week or more, and this should be performed when muscles and joints are warmed up. 
• Balance: Many lower body and core resistance exercises double as balance training, which may reduce the risk of falls even in adults with peripheral neuropathy. Therefore, it is recommended that those with T2D perform balance exercises at least two to three days a week or more. 

Table 2: Recommended Exercise Training for Adults with T2D

Adapted from source.

Regardless of the type of structured exercise done, blood sugar levels and insulin sensitivity similarly improve when energy expenditure is matched. The key is to find what works for you and make exercise an enjoyable part of your routine! Please see Table 2 for a more detailed breakdown of the recommended types of exercise training for adults with T2D. 

Interval Exercise Insights

High-Intensity Interval Exercise (HIIE) has become quite popular lately for its efficiency – offering significant health improvements in a short time. For those with T2D, just one session of HIIE can help control post-meal blood sugar spikes. If you're considering it, here are some key points: Two weeks of afternoon HIIE training can enhance blood sugar levels, but morning sessions might raise glucose levels, especially on an empty stomach. HIIE isn't only about glucose control; it also works wonders for fitness, reducing A1C, and managing BMI in adults with T2D. Compared to continuous walking with the same energy expenditure, HIIE training leads to better fitness, improved body composition, and enhanced glucose control.

However, it's essential to be cautious. Chronic intense training might cause temporary effects like post-exercise blood sugar spikes. Also, be aware of potential risks. A meta-analysis, which is an in-depth review of scientific literature, reported adverse events in 34% of studies, mostly linked to musculoskeletal injuries during HIIE rather than moderate training. This emphasizes the importance of choosing an exercise routine that aligns with your fitness level and overall health. 

Currently, the Physical Activity Guidelines for Americans do not provide specific guidelines for this type of activity. Always consult your healthcare provider before starting a new exercise regimen, especially if you have underlying health conditions. 

Conclusion: Your Path to Better Health 

Getting active is a powerful tool to boost health and manage blood sugar in T2D. These benefits come from improved insulin sensitivity, better regulation of blood sugar following eating, and decreased cardiovascular disease risk. In addition, exercise is a cornerstone of weight loss, which can delay the onset of T2D in at-risk populations and reduce comorbidities. Beyond the physical perks, regular activity also has a positive impact on psychological and cognitive function for individuals with T2D.

You can get all these benefits by following the updated guidelines for Americans, which encourage regular movement, breaks from sitting, and incorporating exercise into your routine. The good news is that exercise is safe and beneficial, even when dealing with health issues. Work with healthcare and exercise experts to tailor a program just for you. 

Consider your journey towards better health as an adventure with the right support system. By including a more active lifestyle into your routine, you’ll enhance your overall well-being and effectively manage blood sugar levels, making strides towards a healthier, happier you. 

Written by Tiffany vanLieshout.

Edited by Michael Stein.

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