INS and Impaired glucose tolerance: One week of restricting sleep to ~5–6 h/night in healthy adults reduced insulin sensitivity by ~20–25%, impaired glucose tolerance, and increased evening blood pressure changes consistent with a pre-diabetic phenotype independent of weight [83,84]. In a within-subject crossover study, acute partial sleep deprivation followed by morning high-intensity interval exercise and a high-fat breakfast altered network interactions between heart-rate variability and LDL cholesterol, suggesting modification or blunting of usual cardioprotective exercise patterns under sleep-deprived conditions [9].