- Late sleep (Ls; 0330-1130 h), Late meals (Lm=meals at 4.5, 8.5, 14.5, and 16 h after awakening)=Ls/Lm Aim 1: To determine whether Ls and/or Lm, in individuals with habitual normal sleep duration and timing, alters one or both sides of energy balance, i.e. food intake and energy expenditure (EE), relative to Ns and Nm.