“Hyperglycaemia, 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 remodelling 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 long clinical history of anti-diabetic medications, the risk of heart failure in people with diabetes never declines. Interestingly, 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 remain unclear.”1
If exercise or physical activities in general have always seemed daunting to you, adjusting the way you view exercise could be a life saver. It’s difficult to justify saying that the benefits of an active lifestyle are underestimated or overlooked considering how often is touted and highly regarded in its advantages for the human body, whether it is to buffer certain conditions and symptoms or if it’s simply to maintain a healthy lifestyle. Nevertheless, despite all its hoopla, physical activity is neglected by many people worldwide despite the obvious pluses it brings to the table. For the purposes of this article, we’ll cover physical activity within the realm of diabetes.
“The endothelium, a monolayer of cells that provides a physical barrier between vessel lumen and vascular wall, is essential in maintaining vascular homeostasis, a process which is recognized to be primarily modulated via its release of a list of mediators that regulate blood coagulation and vascular tone. 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
If exercising has not been part of your daily routine for a while (or ever), you should probably begin at a slower pace and/or light weights. Getting your body used to physical activity may seem daunting at first but there is an amazing variety of workouts that you can do. Slower paced activities such as gardening, mild cycling and going for walks are a great way to begin. If you feel you are up for a more strenuous routine just be sure you have the approval of your doctor.
“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 causes an increase in metabolism speed and function well after your physical activities have been completed, around 24-48 hours after (depending on activity level) according to some research. As your metabolism is boosted by exercise, so is the efficiency of 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 goes up. To truly reap the benefits of an active lifestyle however, it is important to maintain a long-term outlook so as not to lose sight of the bigger picture as it pertains to diabetic conditions. It is about embracing a life improving change (exercise) so that its’ benefits can slowly faze out a detrimental one (diabetes). Obviously, this isn’t to say exercise is a cure for diabetes, rather, with our busy fast paced modern lives, you can use exercise as a tool to mitigate many symptoms of diabetes and thus give yourself more comfort and less hassles in your daily endeavors.
“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. Tjonna et al. demonstrated that both moderate- and high-intensity exercise regimes were able to improve VO2max of metabolic syndrome patients. Data on 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 as it pertains to diabetes is that it has the uncanny ability to lower blood pressure. It is a fact that high blood pressure (HBP) is a major risk factor for heart attacks. It is also a fact that HBP is present in many diabetes patients. The overall boost that regular physical activity provides to your cardiovascular system is considerable. It is recommended by the American College of Sports Medicine that 30 minutes of aerobic exercise be incorporated to your daily routine. Brisk walking, light jogging and swimming are all economical and sufficiently considered great examples of activities you can do.
The icing on the exercise cake is that is helps you lose weight. And, losing weight in turn branches out into a myriad of other benefits. Exercise creates a cascade effect of improved health. Losing weight reduces the propensity to resist insulin, it lowers your blood pressure (see previous paragraph) and it cuts 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 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-hyperglycaemic drugs in the management of diabetic complications, in particular, cardiovascular dysfunction. The exact mechanism(s) that underpin this intriguing synergistic effect remain unclear.”5
“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.”6
An active lifestyle goes a long way in making life a lot easier for diabetic patients for both short and long term. It is also well documented that many patients report no longer needing certain pharmaceuticals to suppress many diabetes complications such as high blood pressure. Significant weight loss has even been reported to lead the remission of diabetes. The bottom line is, with exercise in your diabetes battling arsenal, your health goes up, your costs go down and your future ends-up looking much brighter. Mother Nature provided us with the hardware to improve our body’s health and fight diabetes by simply putting it to work. What else can we ask for?
(1, 4, 5) 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, 6) 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