How does fluo-3 act as a biomarker for neuronal activity? Multiply your body Surface Area x BMR factor to get BASAL METABOLIC RATE in kcal/hour. d. Multiply this figure by 24 hours to get your Basal Metabolic Requirements per day. BMR data Table weight (kgs) height (inches) height (cm) Surface Area BMR factor BMR (m2) (kcal/m2/hr) (kcal/hr) BMR (kcal/day) 2. Physical activity a Estimate your average daily activity level using the Table below: Daily Routine activity level Activity factor Sedentary: mostly sitting, school, desk job, 1.30 clerical work Light activity: working on your feet, but without 1.40 strenuous exertion