Physical activity, including appropriate Endurance and resistance training,
is a major therapeutic modality for type 2 diabetes. Unfortunately, too of
ten physical activity is an underutilized therapy. Favorable changes in glu
cose tolerance and insulin sensitivity usually deteriorate within 72 h of t
he last exercise session: consequently, regular physical activity is impera
tive to sustain glucose-lowering effects and improved insulin sensitivity.
Individuals with type 2 diabetes should strive to achieve a minimum cumulat
ive total of 1000 kcal wk(-1) from physical activities. Those with type 2 d
iabetes generally have a lower level of fitness ((V)over dot O-2max) than n
ondiabetic individuals, and therefore exercise intensity should be at a com
fortable level (RPE 10-12) in the initial periods of training and should pr
ogress cautiously as tolerance for activity improves. Resistance training h
as the potential to improve muscle strength and endurance, enhance flexibil
ity and body composition, decrease risk factors for cardiovascular disease,
and result in improved glucose tolerance and insulin sensitivity. Modifica
tions to exercise type and/or intensity may be necessary for those who have
complications of diabetes. Individuals with type 2 diabetes may develop au
tonomic neuropathy, which affects the heart rate response to exercise, and
as a result, ratings of perceived exertion rather than heart rate may need
to be used for moderating intensity of physical activity. Although walking
may be the most convenient low-impact mode, some persons, because of periph
eral neuropathy and/or foot problems, may need to do non-weightbearing acti
vities. Outcome expectations may contribute significantly to motivation to
begin and maintain an exercise program. Interventions designed to encourage
adoption of an exercise regimen must be responsive to the individual's cur
rent stage of readiness and focus efforts on moving the individual through
the various "stages of change".