SA JOURNAL OF DIABETES & VASCULAR DISEASE
REVIEW
VOLUME 11 NUMBER 2 • JUNE 2014
79
effective intervention early in the progression of disease, and has
some benefits, even in established diabetes. Further, the lifestyle
intervention has documented improvements on other quality-of-life
measures, including sexual functioning in women and obstructive
sleep apnoea, most likely through weight loss.
Perspectives
Exercise is an important part of a healthy lifestyle, particularly
as part of disease prevention rather than cure. Aerobic activity
is recommended by the American Heart Association and the
American College of Sports Medicine to promote and maintain
health, particularly in respect to cardiovascular disease, stroke,
hypertension, type 2 diabetes, obesity, and other common
diseases.
3
Furthermore, incorporation of resistance training may
have additional benefits.
80
Exercise has reduced efficiency in
established type 2 diabetes patients
2
and the duration of diabetes
may also be responsible for the lack of improvement in resting
energy expenditure in diabetic patients.
79
The clinical applicability of
exercise in established diabetes will still improve factors discussed
above, such as improving atherosclerosis
90
and insulin sensitivity.
54
In spite of reported negative results,
4
exercise may also improve
cardiovascular risk factors and prevent the progression to diabetes.
97
Early adoption of an exercise regimen will therefore provide best
results in cardiovascular and metabolic outcomes.
Conclusion
Due to the rising incidence of diabetes and the associated metabolic
diseases such as obesity, cardiovascular disease and hypertension,
lifestyle interventions including diet and exercise are the first line of
defence. The benefits are typically thought of in terms of weight
loss, improved body composition and reduced fat mass, but exercise
can have many other beneficial effects independent of this. Exercise
can affect the vasculature, improving endothelial health. Further,
insulin sensitivity is improved, and the treatment of endothelial
dysfunction may also reduce complications associated with both
diabetes and other metabolic diseases. While the use of drugs to
improve microvascular function in diabetes has previously been
reviewed,
83
exercise can also provide many of the same benefits on
endothelial function, and should remain an early intervention and
the first prescription in combination with diet when treating insulin
resistance and diabetes.
Acknowledgement
This work was supported by two National Institutes of Health
grants, DK27619 and DK29867. Thanks to Josiane Broussard for
editing assistance.
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