They discovered participants’ skeletal muscle mass and strength decreased within days, and some even experienced insulin resistance, which is a common feature of Type 2 diabetes.
They also noted some adults did not fully recover after returning to normal activity.
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"We expected to find that the study participants would become diabetic, but we were surprised to see that they didn't revert back to their healthier state when they returned to normal activity," lead author Chris McGlory said in a statement.
They said their results indicate that seniors who experience periods of inactivity from illness, hospitalization or bed rest, for example, are more likely to have “harmful consequences to their overall health.”
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"Treatment of Type 2 diabetes is expensive and often complicated," coauthor Stuart Phillips, added. "If people are going to be off their feet for an extended period they need to work actively to recover their ability to handle blood sugar."