If exercise or physical activities, in general, appear daunting to you, adjusting the way you view exercise could be a lifesaver. Exercise not only provides general benefits to the whole body but also benefits specific diseases, such as diabetes and its symptoms. Despite all these positive effects, numerous people worldwide neglect physical activity.
Exercise and Heart Disease in Diabetic Patients
Exercise has numerous benefits for weight loss, but also for dealing with multiple risk factors for heart disease in diabetic patients. It normalizes blood sugar and cholesterol levels, enhances high blood pressure, and reduces abdominal fat.
“Hyperglycemia, hypertension, dyslipidemia and insulin resistance collectively impact on the myocardium of people with diabetes, triggering molecular, structural and myocardial abnormalities. These have been suggested to aggravate oxidative stress, systemic inflammation, myocardial lipotoxicity and impaired myocardial substrate utilization. As a consequence, this leads to the development of a spectrum of cardiovascular diseases, which may include but not limited to coronary endothelial dysfunction, and left ventricular remodeling and dysfunction. Diabetic heart disease (DHD) is the term used to describe the presence of heart disease specifically in diabetic patients. Despite significant advances in medical research and a long clinical history of anti-diabetic medications, the risk of heart failure in people with diabetes never declines. Interestingly, a sustainable and long-term exercise regimen has emerged as an effective synergistic therapy to combat the cardiovascular complications in people with diabetes, although the precise molecular mechanism(s) underlying this protection remains unclear.”1
Exercise and Endothelial Dysfunction
“Endothelial dysfunction is referred to the condition where the endothelium loses its physiological properties but shows a tendency towards vasoconstriction, pro-thrombotic, and pro-inflammatory states. In addition to being a well-recognized precursor of atherosclerosis, endothelial dysfunction has also been considered a pathophysiological hallmark characterized by type 2 diabetes. This originates in the evidence that endothelial dysfunction is consistently observed in patients with type 2 diabetes and predicts the risk of incident type 2 diabetes. On the other hand, endothelial dysfunction is recognized to be an initiating and important factor in the development and progression of diabetes-related microvascular and macrovascular complications Since exercise training is a key element in the management of type 2 diabetes, and given that endothelial dysfunction might be a therapeutic target for diabetes, there is a growing interest in exploring the influence of exercise training on endothelial function in patients with type 2 diabetes. However, available studies on this topic have shown inconsistent and inconclusive findings.”2
How to Start Exercising with Diabetes
If exercising has not been part of your daily routine for a while (or ever), you should begin at a slow pace and/or with light weights. Getting your body used to physical activity is daunting at first but a wide variety of workouts will help you start. You could begin with slower-paced activities such as gardening, mild cycling and going for walks. If you feel ready for a more strenuous routine, seek your doctor’s approval first.
“In light of this evidence, diabetes organizations strongly advocate a role for physical activity in the management of diabetes. Much of the advice relates to type 2 diabetes. The ADA (American Diabetes Association) suggests that ‘persons with type 2 diabetes should undertake at least 150 min per week of moderate to vigorous aerobic exercise spread out during at least 3 days during the week, with no more than two consecutive days between bouts of aerobic activity. Aerobic exercise should be at least at moderate intensity, corresponding approximately to 40–60% of VO2max, and the ADA suggests that patients with type 2 diabetes should be encouraged to perform resistance exercise ‘at least twice weekly on non-consecutive days, but more ideally three times a week, as part of a physical activity program for individuals with type 2 diabetes, along with regular aerobic activities. Each training session should minimally include five to ten exercises involving the major muscle groups (in the upper body, lower body, and core) and involve completion of 10–15 repetitions to near fatigue per set early in training, progressing over time to heavier weights (or resistance) that can be lifted only eight to ten times. A minimum of one set of repetitions to near fatigue, but as many as three to four sets, is recommended for optimal strength gains’. There is also guidance on type 1 diabetes stating that all levels of exercise can be performed, and providing guidelines for safe exercise.”3
What’s so powerful about exercise that will help my diabetes?
Your skeletal muscles and brain are the primary users of glucose, the main source of energy from the human diet. Exercise increases metabolism speed and function after completing physical activities, and around 24-48 hours after (depending on activity level). As exercise boosts your metabolism, it also enhances many of your body’s biochemical systems, including the breakdown of glucose and increasing sensitization of your cells to insulin. As a result, blood glucose levels tend to decrease as metabolism efficiency rises.
Another body system that benefits is the aforementioned cardiovascular system. “Exercise has been suggested to restore myocardial function through the improvement of VO2max, endothelial function, left ventricular systolic and diastolic function and blood pressure. VO2max, a strong indicator for cardiorespiratory fitness and an independent predictor of cardiovascular mortality, was improved by 12–16% in obese postmenopausal women and obese individuals with T2DM in response to moderate-intensity exercise. Data on the cardioprotective effects of low-intensity exercise is sparse. This could be due to the fact that low-intensity exercise may not meet the recommended minimum threshold of exercise intensity (e.g. 50% of VO2max) for improving cardiorespiratory endurance.”4
Another benefit of exercise is that it lowers blood pressure. Hypertension or high blood pressure (HBP) is a major risk factor for heart attacks and is present in several diabetic patients.
The American College of Sports Medicine recommends incorporating 30 minutes of aerobic exercise to your daily routine. Brisk walking, light jogging, and swimming are economical and beneficial examples of activities you can do.
An active lifestyle also provides the consequential benefits of losing weight. Exercise creates a cascade effect of improved health. Losing weight reduces the propensity to resist insulin, it lowers your blood pressure (see previous paragraphs) and it decreases cholesterol levels significantly.
“Strict control of blood glucose with pharmacological intervention alone is not sufficient to reduce the risk of major cardiovascular events in people with Type 2 Diabetes Mellitus (T2DM). Indeed, intensive diabetic pharmacotherapy can even exacerbate cardiovascular events in diabetes patients. Yet, exercise as an adjunct with anti-diabetic treatment (either with insulin or oral hypoglycaemic drugs) reduced the incidence of cardiovascular events and improved VO2max in T2DM patients. Meta-analyses on the association between physical exercise with the risk of all-cause mortality and cardiovascular disease further demonstrated that increased physical activity was inversely correlated with cardiovascular risk and mortality in T2DM. Together, this evidence strongly advocates that active physical activity synergizes the effects of anti-hyperglycemic drugs in the management of diabetic complications, in particular, cardiovascular dysfunction. The exact mechanism(s) that underpin this intriguing synergistic effect remain unclear.”6
To reap the benefits of an active lifestyle however, patients must maintain a long-term outlook not to lose sight of the bigger picture as it pertains to diabetic conditions. It is about embracing a life-improving change (exercise) whose benefits can counteract the effects of diabetes. It does not mean exercise is a cure for diabetes, but you can use exercise as a tool to mitigate its symptoms and thus improve your quality of life.
“The weight of evidence for the benefits of physical activity in patients with type 2 diabetes, whilst by no means satisfactory, still exceeds that available for type 1 diabetes. Much of the guidelines applied to patients with type 1 diabetes are based on understanding gained from studies on individuals without diabetes or with type 2 diabetes, both clearly very different conditions. Furthermore, whilst there is evidence that (young and complication-free) patients with type 1 diabetes undertake as much physical activity as people without diabetes, these levels remain suboptimal. There is also a further group of patients who report fear of hypoglycemia as a barrier to physical activity. It is therefore important to clarify the role of physical activity in the management of type 1 diabetes.”7
The overall boost that regular physical activity provides to your cardiovascular system is considerable. An active lifestyle provides numerous long-term and short-term benefits to diabetic patients. Several patients report no longer needing certain pharmaceuticals to suppress some diabetes complications such as high blood pressure. Other patients with significant weight loss have reported exercise has caused the remission of diabetes. The bottom line is, exercise is your ally to battle diabetes, your costs go down and your future appears brighter. If you want to start exercising, seek your doctor for advice on your particular case.
(1, 4, 5, 6) Exercise mediated protection of diabetic heart through modulation of microRNA mediated molecular pathways. Sheng Lew, J.K, Pearson, J.T., Schwenke, D.O. & Katare, R. Cardiovascular Diabetology. 2017. https://cardiab.biomedcentral.com/articles/10.1186/s12933-016-0484-4
(2) Exercise training and endothelial function in patients with type 2 diabetes: a meta-analysis. Qiu, S., Cai, X., Yin, H., Sun, Z., Zügel, M., Steinacker, J.M. & Schumann, U. Cardiovascular Diabetology. 2018. https://cardiab.biomedcentral.com/articles/10.1186/s12933-018-0711-2
(3, 7) What are the health benefits of physical activity in type 1 diabetes mellitus? A literature review. Chimen, M., Kennedy, A., Nirantharakumar, K. et al. Diabetologia. 2012. https://link.springer.com/article/10.1007%2Fs00125-011-2403-2