By Sheri Colberg, PhD
It used to be common knowledge that you should stretch before and after physical activities for a variety of reasons.
Stretching was supposed to reduce our risk of getting acute injuries, like muscle strains and joint pain. Some of us just did it because we would feel our muscles tighten up during activities, and stretching made us feel more limber and less restricted. Then new research came along that claimed that we were not less likely to get injured if we stretched, and some studies even indicated that stretching before activities — especially power ones — reduces athletic performance.
In spite of the recommendations of the latest exercise guidelines, I firmly believe that the de-emphasis of flexibility training as an integral part of physical activity programs is misguided and actually harmful, especially to people with diabetes whose primary focus is not simply whether or not stretching reduces their risk of acute injuries during physical activity. On the contrary, limited joint mobility is a common problem that is frequently observed in elderly people and in patients with diabetes and can by itself lead to injury and substantially lower their quality of life.
The main causes of a reduced range of motion (ROM) around joints are degenerative joint diseases and increased stiffness of collagen tissue (2). As the result of both aging and elevated blood sugar levels, collagen around joint surfaces can become glycated — due to formation of advanced glycation end products (AGEs) — which causes more collagen cross-linkages to form. Such glycation occurs most frequently in tissues with a low protein turnover, such as the collagen in the extracellular matrix of articular capsule, ligaments and muscle-tendon units, and results in decreased elasticity and tensile strength and increased stiffness. Poorly-controlled diabetes simply speeds up the process that aging starts.
What can be done to prevent joint stiffness related to these changes? Obviously, tighter blood glucose management is critical to limit formation of AGEs, but so is consuming a diet rich in antioxidants that can limit oxidative stress and potential damage caused by any AGEs that are formed. Moreover, it would be foolhardy to abandon any attempt to stretch joints to increase mobility. Even if stretching may reduce somewhat power performance and may not prevent acute injuries related to physical activity, it has other critical, positive benefits, especially in an aging diabetic population.
For example, at least one research study showed that most patients who have phase-II idiopathic adhesive capsulitis ("frozen shoulder") common to people with diabetes can be successfully treated with a specific four-direction shoulder-stretching exercise program (3). We have also shown that including a program of stretching with resistance training can increase ROM in individuals with type 2 diabetes and allow them to more easily engage in activities that require greater ROM around joints (4). Some of our more recent research suggests that flexibility is a component of enhanced balance and can reduce the risk of falls that negatively impact health and quality of life in an aging population (5).
While I am not recommending that you completely replace aerobic, resistance, and other types of physical training programs with flexibility training alone, I do strongly recommend that everyone include stretching as an integral component of a normal training regimen. Stretches can be done before and/or after training or anytime that joints feel stiff or movement restricted. Generally, stretching is easier when you are already warmed up (i.e., the synovial fluid in the joints also heats up and facilitates movement), and stretches can be either static (held for 10-30 seconds per stretch) or dynamic (using a greater ROM around joints during active movement). Doing yoga can be beneficial as well and may help lower stress levels as a side benefit.
Feel free to direct your patients to the illustrated upper and lower stretches available online in PDF format and accessible here: http://www.lifelongexercise.com/FlexibilityExercises-LEI.pdf.
- Colberg SR, Sigal RJ, Fernhall B, Regensteiner JG, Blissmer BJ, Rubin RR, Chasan-Taber L, Albright AL, Braun B; American College of Sports Medicine; American Diabetes Association. Exercise and type 2 diabetes: the American College of Sports Medicine and the American Diabetes Association: joint position statement. Diabetes Care. 2010;33(12):e147-67.
- Abate M, Schiavone C, Pelotti P, Salini V. Limited joint mobility in diabetes and ageing: recent advances in pathogenesis and therapy. Int J Immunopathol Pharmacol. 2010;23(4):997-1003.
- Griggs SM, Ahn A, Green A. Idiopathic adhesive capsulitis. A prospective functional outcome study of nonoperative treatment. J Bone Joint Surg Am. 2000 Oct;82-A(10):1398-407.
- Herriott MT, Colberg SR, Parson HK, Nunnold T, Vinik AI. Effects of 8 weeks of flexibility and resistance training in older adults with type 2 diabetes. Diabetes Care. 2004;27(12):2988–9.
- Morrison S, Colberg SR, Mariano M, Parson HK, Vinik AI. Balance training reduces falls risk in older individuals with type 2 diabetes. Diabetes Care. 2010;33(4):748-50.