"Thus, it may seem paradoxical that some of the changes observed in the present study during weight loss prevented an increase in insulin sensitivity."
Here are the metrics from Table 2
The subjects were divided on the basis of the direction of this change in M score resulting from weight loss.
Prolonged Fasting Identifies Skeletal Muscle Mitochondrial Dysfunction as Consequence Rather Than Cause of Human Insulin Resistance
which combines a Dutch version of the M score with indirect calorimetry during the steady state conditions of the clamp. Neat hey? This time weight loss was not from an hypocaloric diet, it was from a zero caloric diet, ie extended fasting, which sources calories from a minimal carbohydrate, minimal protein, very high fat source, ie the subject's own body catabolism. Just for 60 hours. But by the end nearly 100% of calories from are fat oxidation.
Fat metabolism in formerly obese women