Structured exercise interventions of at least eight weeks duration have been shown to lower HbA1c by an average of 0.66 percent in people with type 2 diabetes, even with no significant change in body mass index (ADA, 2013). Higher levels of exercise intensity are associated with greater improvements in HbA1c and in fitness (ADA, 2015). For adults over the age of 18, the accumulation of 150 minutes of moderate-intensity aerobic physical activity (40 to 60 percent of maximal oxygen uptake or 50 to 70 percent of maximum heart rate) per week with no more than two consecutive days between bouts of aerobic activity, in addition to resistance/strength training that involve all major muscle groups three times per week on nonconsecutive days is recommended (ADA, 2013), (S. Colberg, R. Sigal and B. Fernhall et al. 2010), (Franz et al. 2010), (Sigal et al. 2004). In a meta-analysis of eight randomized controlled trials and 18 observational studies, people who used pedometers increased their physical activity by 27 percent over baseline. In this analysis, having a goal (e.g., taking 10,000 steps per day) was as an important predictor of increased physical activity (S. Colberg, R. Sigal and B. Fernhall et al. 2010).
Physical Activity with Type 2 Diabetes Photo Gallery
Independent of weight loss, both aerobic exercise and resistance training have been found to improve glycemic control and reduce cardiovascular disease risk factors. For those individuals already exercising at moderate intensity, to obtain even greater benefits in glycemic control and aerobic fitness, increasing the intensity even more is recommended. For adults over the age of 65 and for those with disabilities, the adult guidelines should be followed if possible, or if not possible, individuals should be encouraged to be as physically active as they are able (ADA, 2013). In older men with type 2 diabetes, progressive resistance exercise improves insulin sensitivity to the same or even greater extent as aerobic exercise. Clinical trials have provided strong evidence for the HbA1c-lowering value of resistance training and for an additive benefit of combined aerobic and resistance exercise (ADA, 2013).
Overall, the improvement in insulin sensitivity and the decrease risk for cardiovascular disease (e.g., through reduced LDL levels) and allcause mortality has been shown with appropriate physical activity (Franz et al. 2010). No more than two consecutive days should pass without physical activity, in order to achieve long-term glycemic control (Franz et al. 2010), (Sigal et al. 2004). Before undertaking exercise that is more intense than brisk walking, sedentary persons with type 2 diabetes should consult a primary care practitioner (PCP). Electrocardiogram (ECG) exercise stress testing for asymptomatic individuals at low risk of CVD is not recommended but may be indicated for those who are at high risk (S. Colberg, R. Sigal and B. Fernhall et al. 2010). The general recommendations for diabetes from the American Diabetes Association Standards of Care in Diabetes 2015 are listed in Table 2.3.