This study will require participants to stay in the room calorimeters for up to 5 hours on each of the 3 test sessions. The participants are to avoid intense physical activity/alcohol and to record their food intake for the day prior to test day. They will record their food intake for the day prior to test session 1 in a food diary (to be provided to them on the day of screening). Records will be used to ascertain participants' food intake patterns. They will report to Clinical Nutrition Research Centre (CNRC) in the morning after an overnight (10-12 hours) fast. Basic anthropometric measurements will be taken at the start of the test session before participants enter the room calorimeter. The room calorimeter is a 13.5 m3 chamber furnished with features to give an impression of a normal room with windows on three sides of the chamber for outside view and visual contact with researchers. It has a full sized foldaway bed, a fold-down writing table, an office chair, a built-in sink and mirror, a portable freeze-dry toilet bowl, a television, a telephone, computer network connection, an intercom system. During their stay in the room calorimeter, energy expenditure will be measured based on recorded oxygen consumption and carbon dioxide production over 10 hours. Participants are allowed to rest, sit and move freely, except sleep or exercise during their stay. On each of the 3 test sessions, the subjects will perform up to 4 common household activities (e.g. mopping floor, washing dishes, etc) 1 hour after consuming the light breakfast. On test session 1, the light breakfast consist of biscuits and a juice drink and will be provided to the participants after they have undergone assessment of metabolism at rest for approximately 45 minutes in the room calorimeter. On test session 2 and 3, the same light breakfast will be provided after approximately 15 minutes after they have entered the room calorimeter. During their 4-5 hours stay in the room calorimeter, they will simulate a particular household activity for up to 20 minutes and rest for 30 minutes before continuing with another household activity and so on for up to 4 different household activities at each of the test sessions.