To investigate the relationship between glucose metabolism, such as intra-individual blood glucose variability, and body composition, mainly muscle mass, we conducted daily blood glucose monitoring tests using FGM devices and body composition analysis tests using InBody770 in three regions of CIRCS, a regional cohort study. The subjects were non-diabetic; 448 residents (166 men and 282 women) aged 40-74. We used multivariable analysis to quantitatively examine the association between suspected postprandial hyperglycemia, glycemic spikes, glycemic variability, insulin secretion capacity/resistance, and five muscle mass indices. As a result, there is no significant association between glycemic variability indices and muscle mass indices. On the other hand, a significant negative association was found between the percentage of limb skeletal muscle in total body muscle mass and the risk of insulin resistance.