Managing diabetes demands careful attention to diet, physical activity, and lifestyle. For those who train regularly or are involved in sports, managing diabetes can be all the more challenging. However, when done right, it can also be empowering if one takes the time to understand some of the fundamentals.
Exercise has well-documented benefits for blood sugar control (1), but it also demands a deeper understanding of the interplay between physical activity, diet, and specific supplements. All three can work together to optimize blood sugar stability and maximize performance.
This article explores practical yet effective strategies for managing diabetes through diet, lifestyle modifications, and targeted supplementation, including sports supplements that support training and blood glucose balance.
1. UNDERSTANDING THE IMPACT OF EXERCISE ON BLOOD GLUCOSE
Exercise has a profound impact on blood glucose levels. Aerobic (e.g., running, cycling) and anaerobic (e.g., weightlifting, high-intensity interval training) activities help improve insulin sensitivity, allowing muscle cells to absorb glucose more effectively, which in turn helps lower blood sugar levels (2). Evidence suggests that aerobic exercise increases glucose uptake by muscles fivefold, and moderate-intensity exercise can lower blood sugar for up to 24 – 48 hours post-workout by increasing insulin sensitivity (3).
However, managing diabetes while training requires a proactive approach due to the body’s increased glucose demand during and after exercise. Hypoglycemia (low blood sugar) is a risk during prolonged or intense exercise sessions (4), while some high-intensity workouts may temporarily elevate blood glucose due to the stress response (5). Understanding these dynamics allows individuals with diabetes to tailor their workouts and dietary strategies accordingly.
2. DIETARY STRATEGIES FOR BLOOD GLUCOSE MANAGEMENT DURING TRAINING
Carbohydrate Timing and Quality
Carbohydrate intake is crucial for people with diabetes, especially those engaged in regular physical activity. A key strategy is carbohydrate timing—consuming the right carbohydrates alongside protein and fat before training can help stabilize blood sugar levels while providing sustained energy during the workout (6). For instance, consuming a meal with whole grains, sweet potatoes, or legumes about 1–2 hours before exercise ensures a steady glucose release, reducing the risk of rapid blood sugar fluctuations (7). Complimenting these carbs with some protein will further stabilize blood sugar.
Post-exercise, carbohydrate intake helps replenish glycogen stores but should be balanced with protein to support muscle recovery and prevent blood sugar spikes (8). The American Diabetes Association suggests a balanced macronutrient (Carbs, Fats, Proteins) profile in post-exercise meals, with an emphasis on high-fibre carbohydrates to prevent rapid glucose elevation (9).
Protein and Fat Considerations
Including protein in each meal, especially post-workout, can support muscle repair and provide a steady release of energy. Protein sources like lean meat, eggs, tofu, and low-fat dairy have minimal impact on blood sugar and can help stabilize glucose levels throughout the day. Research has shown that consuming whey protein decreases postprandial glycemia [levels of glucose (i.e. sugar) in the blood after a meal] and regulates blood sugar (10). Eating moderate amounts of healthy fats from sources like nuts, olive oil, avocados, and fish further aids blood sugar control by slowing the digestion of carbohydrates (11).
Avoiding Sugary Foods and Refined Carbs
While high-glycemic carbohydrates (e.g., sugary drinks, white bread) may seem like a quick energy fix, they can cause a rapid spike and subsequent crash in blood glucose, particularly post-exercise (12). These fluctuations can increase insulin demand and impair long-term blood sugar control, making it essential for people with diabetes to focus on low-glycemic, high-fibre options that promote steady energy.
3. LIFESTYLE MODIFICATIONS TO ENHANCE BLOOD SUGAR STABILITY
Consistent Sleep Patterns
Sleep quality significantly impacts insulin sensitivity. Inadequate or poor quality sleep increases stress hormones like cortisol, which can elevate blood glucose levels and impair insulin response (13). A 2015 study found that six consecutive nights of sleep restriction increased evening cortisol levels while decreasing glucose effectiveness and insulin response by 30% (14). With so many individuals watching TV or using their cellphones right before bed, evidence suggests that the blue light given off by these devices alters circadian rhythms and induces insulin resistance (15). Try using blue light filtering glasses an hour or two before bed when exposed to blue light and see if it helps with sleep. These glasses are inexpensive yet very effective. For individuals managing diabetes, prioritizing consistent sleep patterns is essential, especially when training regularly. Aim for 7–9 hours of quality sleep each night to support optimal insulin sensitivity.
Stress Management Techniques
Stress triggers cortisol release, which can elevate blood sugar levels (16). A 2022 study suggests that psychological and physical stress may be the triggers that initiate type 2 diabetes (17). Incorporating stress management techniques—such as mindfulness meditation, deep breathing exercises, or yoga—can aid in maintaining stable blood glucose levels. Physical activities like yoga also contribute to flexibility and strength while promoting mental calm, a benefit for those managing both diabetes and the demands of regular exercise.
4. SUPPLEMENTATION FOR DIABETES MANAGEMENT AND ATHLETIC PERFORMANCE
Certain dietary supplements can be valuable in managing blood glucose levels while supporting exercise performance (18). Before starting any supplement regimen that impacts blood sugar, individuals with diabetes, especially those on medications, should always consult their healthcare providers first.
Whey Protein
Whey protein has long been a staple in the diets of exercise enthusiasts and athletes alike, and for good reason. No other protein is as effective at muscle protein synthesis and repair (19). More recently, however, it has also been shown to improve postprandial glycaemia (blood sugar levels after a meal) and has been proposed as a promising protein option for those with type 2 diabetes (20).
Creatine Monohydrate
Creatine is one of the most widely used and researched sports supplements today. With over 1000 studies, creatine monohydrate is the most extensively studied form of creatine (21). Evidence has shown that creatine improves exercise performance, supports training adaptations, enhances post-exercise recovery, reduces the risk of injury, regulates body temperature during exertion, helps with rehabilitation, and protects against concussive injuries (22) More recently, studies have shown that creatine may improve glucose metabolism in both healthy individuals and those with type 2 diabetes (23,24). Although this recent evidence is limited, it shows enough promise that researchers have suggested it should be investigated further in people with diabetes (25).
Magnesium
Over the last few years, magnesium has stepped into the spotlight. Our understanding of this mineral’s critical role in health has led to an increasing number of consumers supplementing with it daily. Once only thought of in the context of muscle relaxation and its supporting role alongside calcium for bone health, we now recognize that magnesium is also essential for glucose metabolism, and deficiency has been linked to an increased risk of insulin resistance (26). Evidence suggests that clinical hypomagnesemia (low levels of magnesium in the blood) is common among those with type 2 diabetes (27). Supplementing with magnesium for as little as three months reduces insulin resistance and improves glycemic control in individuals with type 2 diabetes (28). Ensuring adequate magnesium intake through foods (such as leafy greens, nuts, and seeds) or supplements can improve blood sugar regulation. Pumpkin seeds and hemp hearts are particularly rich in magnesium.
Vitamin D
Over the years, vitamin D’s impact on our health has expanded dramatically. Consequently, experts have recommended increasing the dose from decade to decade, particularly in countries with long winters (29). One study found that 72% of individuals with type 2 diabetes were vitamin D deficient at the beginning of the study. After taking 4,500 IU daily for two months, their blood sugar levels improved significantly (30) Vitamin D can also support “optimal muscle function, reduce inflammation and pain, increase muscle protein synthesis, ATP concentration, strength, jump height, jump velocity, jump power, exercise capacity, and physical performance” (31). Also noteworthy is that a magnesium deficiency can compromise the ability to synthesize vitamin D (32).
Chromium
Chromium is a trace mineral that may enhance insulin action and improve glucose tolerance by supporting insulin receptor activity (33). Some studies suggest chromium picolinate may help stabilize blood glucose levels in people with diabetes, particularly when combined with a balanced diet and exercise (34). One study looked at the mineral levels of blood, urine, and scalp hair and found that chromium, zinc, and manganese levels were lower in diabetics vs non-diabetics (35).
Berberine
Berberine, a natural compound found in plants like European barberry, goldenseal, and Oregon Grape, has shown promising effects in managing blood sugar (36). Studies reveal that it can lower fasting blood glucose levels, improve insulin sensitivity, and even mimic some effects of metformin, a common diabetes medication (37). Berberine may also support cardiovascular health, a key concern for those with diabetes who are active in sports or resistance training (38).
5. PRACTICAL TIPS FOR TRAINING WITH DIABETES
For individuals with diabetes engaged in regular training, a few additional tips can help balance exercise and blood glucose management:
-
Monitor Blood Glucose Levels: Testing blood glucose before, during, and after workouts can help understand individual responses to exercise and make necessary adjustments.
-
Stay Hydrated: Dehydration can elevate blood sugar levels, so staying hydrated is crucial for those with diabetes. Electrolyte-rich fluids can be particularly helpful for endurance athletes.
- Adjust Insulin Dosage Carefully: If using insulin, consult a healthcare provider about adjusting dosages on training days to prevent hypoglycemia or hyperglycemia. Exercise can change insulin needs, and proper guidance is essential.
CONCLUSION
Training with diabetes is highly beneficial, provided it’s approached with careful planning and a clear understanding of how diet, lifestyle, and supplementation interact with blood glucose management. By focusing on nutrient-dense foods, strategic supplementation, and consistent lifestyle practices, individuals with diabetes can optimize both their athletic performance and blood glucose control. Remember to consult with a healthcare provider before making significant changes, especially in relation to supplementation and insulin adjustments, to ensure safe and effective diabetes management during training.
By: Nelson Narciso, DNM®
References
1 Zahalka SJ, Abushamat LA, Scalzo RL, et al. The Role of Exercise in Diabetes. [Updated 2023 Jan 6]. In: Feingold KR, Anawalt B, Blackman MR, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK549946/
2 Ibid.
3 Colberg, S. R., Sigal, R. J., Yardley, J. E., Riddell, M. C., Dunstan, D. W., Dempsey, P. C., Horton, E. S., Castorino, K., & Tate, D. F. (2016). Physical Activity/Exercise and Diabetes: A Position Statement of the American Diabetes Association. Diabetes care, 39(11), 2065–2079. https://doi.org/10.2337/dc16-1728
4 Younk, L. M., Mikeladze, M., Tate, D., & Davis, S. N. (2011). Exercise-related hypoglycemia in diabetes mellitus. Expert review of endocrinology & metabolism, 6(1), 93–108. https://doi.org/10.1586/eem.10.78
5 Adams O. P. (2013). The impact of brief high-intensity exercise on blood glucose levels. Diabetes, metabolic syndrome and obesity : targets and therapy, 6, 113–122. https://doi.org/10.2147/DMSO.S29222
6 Scott, S., Kempf, P., Bally, L., & Stettler, C. (2019). Carbohydrate Intake in the Context of Exercise in People with Type 1 Diabetes. Nutrients, 11(12), 3017. https://doi.org/10.3390/nu11123017
7 Burke, L. M., van Loon, L. J. C., & Hawley, J. A. (2017). Postexercise muscle glycogen resynthesis in humans. Journal of applied physiology (Bethesda, Md. : 1985), 122(5), 1055–1067. https://doi.org/10.1152/japplphysiol.00860.2016
8 Layman, D. K., Clifton, P., Gannon, M. C., Krauss, R. M., & Nuttall, F. Q. (2008). Protein in optimal health: heart disease and type 2 diabetes. The American journal of clinical nutrition, 87(5), 1571S–1575S. https://doi.org/10.1093/ajcn/87.5.1571S
9 American Diabetes Association (2018). 4. Lifestyle Management: Standards of Medical Care in Diabetes-2018. Diabetes care, 41(Suppl 1), S38–S50. https://doi.org/10.2337/dc18-S004
10 Lesgards J. F. (2023). Benefits of Whey Proteins on Type 2 Diabetes Mellitus Parameters and Prevention of Cardiovascular Diseases. Nutrients, 15(5), 1294. https://doi.org/10.3390/nu15051294
11 Collier, G., McLean, A., & O'Dea, K. (1984). Effect of co-ingestion of fat on the metabolic responses to slowly and rapidly absorbed carbohydrates. Diabetologia, 26(1), 50–54. https://doi.org/10.1007/BF00252263
12 Vlachos, D., Malisova, S., Lindberg, F. A., & Karaniki, G. (2020). Glycemic Index (GI) or Glycemic Load (GL) and Dietary Interventions for Optimizing Postprandial Hyperglycemia in Patients with T2 Diabetes: A Review. Nutrients, 12(6), 1561. https://doi.org/10.3390/nu12061561
13 Hirotsu, C., Tufik, S., & Andersen, M. L. (2015). Interactions between sleep, stress, and metabolism: From physiological to pathological conditions. Sleep science (Sao Paulo, Brazil), 8(3), 143–152. https://doi.org/10.1016/j.slsci.2015.09.002
14 Spiegel, K., Leproult, R., & Van Cauter, E. (1999). Impact of sleep debt on metabolic and endocrine function. Lancet (London, England), 354(9188), 1435–1439. https://doi.org/10.1016/S0140-6736(99)01376-8
15 Nagai, N., Ayaki, M., Yanagawa, T., Hattori, A., Negishi, K., Mori, T., Nakamura, T. J., & Tsubota, K. (2019). Suppression of Blue Light at Night Ameliorates Metabolic Abnormalities by Controlling Circadian Rhythms. Investigative ophthalmology & visual science, 60(12), 3786–3793. https://doi.org/10.1167/iovs.19-27195
16 Sharma, K., Akre, S., Chakole, S., & Wanjari, M. B. (2022). Stress-Induced Diabetes: A Review. Cureus, 14(9), e29142. https://doi.org/10.7759/cureus.29142
17 Ibid.
18 Kubala, J. (2023, September 28). 14 supplements to help lower blood sugar. Healthline. https://www.healthline.com/nutrition/blood-sugar-supplements
19 van Loon L. J. (2013). Role of dietary protein in post-exercise muscle reconditioning. Nestle Nutrition Institute workshop series, 75, 73–83. https://doi.org/10.1159/000345821
20 Mignone, L. E., Wu, T., Horowitz, M., & Rayner, C. K. (2015). Whey protein: The "whey" forward for treatment of type 2 diabetes?. World journal of diabetes, 6(14), 1274–1284. https://doi.org/10.4239/wjd.v6.i14.1274
21 Kreider, R. B., Kalman, D. S., Antonio, J., Ziegenfuss, T. N., Wildman, R., Collins, R., Candow, D. G., Kleiner, S. M., Almada, A. L., & Lopez, H. L. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition, 14, 18. https://doi.org/10.1186/s12970-017-0173-z
22 Ibid.
23 Solis, M. Y., Artioli, G. G., & Gualano, B. (2021). Potential of Creatine in Glucose Management and Diabetes. Nutrients, 13(2), 570. https://doi.org/10.3390/nu13020570
24 Gualano, B., Novaes, R., Artioli, G. et al. Effects of creatine supplementation on glucose tolerance and insulin sensitivity in sedentary healthy males undergoing aerobic training. Amino Acids 34, 245–250 (2008). https://doi.org/10.1007/s00726-007-0508-1
25 Ibid.
26 Morais, J. B. S., Severo, J. S., de Alencar, G. R. R., de Oliveira, A. R. S., Cruz, K. J. C., Marreiro, D. D. N., Freitas, B. J. E. S. A., de Carvalho, C. M. R., Martins, M. D. C. C. E., & Frota, K. M. G. (2017). Effect of magnesium supplementation on insulin resistance in humans: A systematic review. Nutrition (Burbank, Los Angeles County, Calif.), 38, 54–60. https://doi.org/10.1016/j.nut.2017.01.009
27 Barbagallo, M., & Dominguez, L. J. (2015). Magnesium and type 2 diabetes. World journal of diabetes, 6(10), 1152–1157. https://doi.org/10.4239/wjd.v6.i10.1152
28 ELDerawi, W. A., Naser, I. A., Taleb, M. H., & Abutair, A. S. (2018). The Effects of Oral Magnesium Supplementation on Glycemic Response among Type 2 Diabetes Patients. Nutrients, 11(1), 44. https://doi.org/10.3390/nu11010044
29 Duff, D. (2023, November 27). Vitamin D recommended levels should be 10x higher: Report. New York Post. https://nypost.com/2023/11/27/lifestyle/vitamin-d-recommended-levels-should-be-10x-higher-report/
30 Mohamad, M. I., El-Sherbeny, E. E., & Bekhet, M. M. (2016). The Effect of Vitamin D Supplementation on Glycemic Control and Lipid Profile in Patients with Type 2 Diabetes Mellitus. Journal of the American College of Nutrition, 35(5), 399–404. https://doi.org/10.1080/07315724.2015.1026427
31 Shuler, F. D., Wingate, M. K., Moore, G. H., & Giangarra, C. (2012). Sports health benefits of vitamin d. Sports health, 4(6), 496–501. https://doi.org/10.1177/1941738112461621
32 Rosanoff, A., Dai, Q., & Shapses, S. A. (2016). Essential Nutrient Interactions: Does Low or Suboptimal Magnesium Status Interact with Vitamin D and/or Calcium Status?. Advances in nutrition (Bethesda, Md.), 7(1), 25–43. https://doi.org/10.3945/an.115.008631
33 Dubey, P., Thakur, V., & Chattopadhyay, M. (2020). Role of Minerals and Trace Elements in Diabetes and Insulin Resistance. Nutrients, 12(6), 1864. https://doi.org/10.3390/nu12061864
34 Ibid.
35 Ibid.
36 U.S. National Library of Medicine. (2024). Berberine: Supplement information. MedlinePlus. https://medlineplus.gov/druginfo/natural/1126.html
37 Neag, M. A., Mocan, A., Echeverría, J., Pop, R. M., Bocsan, C. I., Crişan, G., & Buzoianu, A. D. (2018). Berberine: Botanical Occurrence, Traditional Uses, Extraction Methods, and Relevance in Cardiovascular, Metabolic, Hepatic, and Renal Disorders. Frontiers in pharmacology, 9, 557. https://doi.org/10.3389/fphar.2018.00557
38 Ibid.
