How exactly is eating no sugar or fruit a starvation diet? You're way off on this one.
"They subject the body to starvation and produce an average weekly weight loss of 3.3–5.5 lb."
If 5.5lb a week is the result of starvation, what might 7lbs/week be? It continues by cautioning about the dangers of such diets.
Just because you eat, doesn't mean you can't starve. Consider protein poisoning (aka, rabbit starvation).
I would presume, however, that when adequate (or some) caloric intake is maintained, esp in the form of amino acids, that this liberation of aa's from muscle is somewhat inhibited
You may be thinking of gluconeogenesis.