How many calories do I need each day?

Energy requirements are based on multiple factors including training frequency, type, intensity, body composition, size, and goals. The formulas and recommendations are not set in stone. It is important to use a multitude of tools to determine if you’re achieving proper energy balance such as appetite, weight, mood, body fat percentage, and overall health.

The human body uses about 60% of calories just to keep up with natural processes at rest. The amount of calories you burn at rest is termed your resting metabolic rate (RMR). The more lean muscle mass you have the higher your RMR. By building a leaner more muscular physique you increase your calorie burning abilities around the clock!

The remainder of the energy pie is divided between activity and digestion. 30% of energy (calories) is used for physical activity while 10% is used in the process of digestion.  This is why you can burn more calories by eating smaller meals more often.

To determine your resting metabolic rate (RMR), aka how many calories your body burns at rest, use the following formula:

W= weight in kilograms              (weight (lbs)/2.2)=weight in kgs

H= height in centimeters               (inches x 2.54)=height in cm

A=age in years

Men: RMR=66.47+(13.75 x W)+(5.0 x H)- (6.75 x A)

Women: RMR=665.09 +(9.56 x W)+(1.84 x H)- (4.67 x A)

Source: Amirkalali, Bahareh, et al. "Comparison of Harris Benedict and Mifflin-ST Jeor equations with indirect calorimetry in evaluating resting energy expenditure." Indian Journal Of Medical Sciences 62.7 (2008): 283-290. MEDLINE with Full Text. EBSCO. Web. 28 June 2010.

Looking for quick and easy?

Use the Rule of Ten (or Eleven):

RMR= 10 calories/pound of bodyweight for women

RMR= 11 calories/pound of bodyweight for men

Example: If you weigh 200 lbs your RMR is 2,200 calories.

• Note: The above equations do not account for individual body composition.

But this one does:

Sterling-Pasmore Equation

This equation is based on your body composition. You need 13.8 calories to support 1 pound of lean muscle mass. 

RMR= Lean body mass (lbs) x 13.8 calories

• You can obtain your lean body mass from body fat measurements (see Assessments in course 1)

Calculate lean muscle mass vs. fat mass:

• Body fat % x scale weight= fat mass
• Scale weight – fat mass= lean body mass

Once you calculate your RMR factor in activity to account for calories burned during exercise.

RMR x 1.2 for low intensity activities and leisure activities (primarily sedentary)

RMR x 1.375 for light exercise (leisurely walking for 30-50 minutes 3-4 days/week, golfing, house chores)

RMR x 1.55 for moderate exercise 3-5 days per week (60-70% MHR for 30-60 minutes/session)

RMR x 1.725 for active individuals (exercising 6-7 days/week at moderate to high intensity (70-85% MHR) for 45-60 minutes/session)

RMR x 1.9 for the extremely active individuals (engaged in heavy/intense exercise like heavy manual labor, heavy lifting, endurance athletes, competitive team sports athletes 6-7 days/week for 90 + minutes/session)

Energy Requirements for Athletes

Athletes require the proper nutrition to fuel performance. This varies depending on the sport and the individual.

Daily Energy Intake Recommendations

Remember to convert weight in pounds (lb) to kilograms (kg) by dividing your weight in pounds by 2.2 to equal weight in kilograms.

Sedentary men and nonpregnant women: Approximately 31 calories/kg

Male and nonpregnant female recreational athletes: Approximately 33-38 calories/kg

Endurance athletes: 35-50 calories/kg depending on training

Strength-trained athlete: 30-60 calories/kg depending on training

Source: Dunford, Marie. Advanced Exercise Nutrition: Version 1.1. Human Kinetics, Inc. Champaign, Il. 2007.

How many calories to build muscle mass and gain weight

Athletes should increase their total caloric intake by 250-500 calories per day to gain weight. Some experts even recommend a 1,000 caloric increase per day. Remember to consider activity level when calculating caloric intake. Athletes should aim to consume the proper ratios of nutrients.

Studies have indicated that the timing of protein intake may be more beneficial for building lean muscle mass rather than quantity since the body can only absorb about 30 grams of protein at a time. Athletes should consume protein and carbohydrates within the first 30-60 minutes post training since the body is in an ideal state to repair and build. Sufficient nutrient intake from clean food sources at multiple times throughout the day will provide the body with the fuel it needs to build lean hard muscle.

How many calories to lose weight?

Athletes should decrease their total caloric intake by 500 calories per day to lose 1 pound in 1 week. The caloric deficit can be created from additional exercise, diet, or a combination of both. Remember to consider activity level when calculating caloric intake. Athletes should aim to consume the proper ratios of nutrients.

Just cutting calories alone may reduce the number on the scale, but losing body fat while maintaining hard earned lean muscle mass is a science. When trying to lose body fat and obtain a lean healthy body it’s important to maintain training intensity. Caloric intake should not drop so low that training severely suffers, metabolism slows, or the body becomes catabolic.  Losing weight and reducing body fat is a gradual process- for lasting results aim to lose no more than 1-2 pounds per week through training and diet.