CALORIE BURN

Consuming the approximate number of calories that our body burns each day is the first step toward attaining peak performance.

Too Much or Too Little Energy

The body’s primary source of energy is carbohydrates (discussed in detail later) but, we don’t store many carbs in our body to use later for energy. However, we do have muscle and lean tissues (like our skin and other organs) and fat stores. Therefore, when your body runs out of stored carbohydrates, then it starts to break down both your protein stores (muscle) and your fat stores.

What is a Calorie

When you hear the word energy, think calories. Calories are nothing more than the body’s “gas” – the energy it needs to move from one place to another. While dieters curtail calories in hopes of shedding body fat, athletes must look at calories as fuel to perform at peak levels of intensity —  to get the body to grow and respond to training.

What is Metabolism?

Metabolism (also called metabolic rate) is the total energy needed for all of the chemical reactions in your body. It includes the energy you need to: think, sleep, breathe, digest food, blink your eyes, and to keep your heart beating – every little thing your body must do to function. Your metabolic rate depends on your age, gender, height, activity level, and how much muscle your body contains.

Consume Enough Calories

You may be thinking: That doesn’t sound good! And you’re right! As an athlete, there is never a good time when you would want to break down your muscles and other lean tissues. Therefore, unless you need to lose body fat, or if you weigh more than a healthy weight, then you want to make sure you are eating enough calories to support your current weight. Having enough calories keeps your body from using itself (muscle) for energy! The loss of lean muscle tissue will result in:

• Increase in fat mass.
• Reduced speed, strength & power.
• Diminish performance capability.
• Lead to over-training and possible injury.

Nutrition & Training Adaptation

If you get anything from this sports nutrition guide, get this: when you strength train, condition, practice, or compete, you are getting WEAKER, NOT STRONGER! When you train, you are depleting energy systems and breaking down muscle tissue through repetitive muscle contraction (ex, running, jumping, sprinting). Not until after you train and you begin refueling the body with the proper nutrients that optimal performance and recovery get facilitated through the body. We refer to this as “training adaptation,” which allows for the highest degree of speed, strength and power development, resulting in a more significant training effect and enhanced performance.

You may be left wondering, how many calories (energy) do I need? Scientists who study the body’s metabolism have created calculations that determine the body’s calorie burn and are the sum of three dimensions that include basal metabolic rate (BMR), daily activity level, and body composition.

What Is My Calorie Burn?

Critical Reload has developed a Performance Nutrition Calculator to assist with determining your daily calories needs uniquely specific to your metabolic rate, age, gender, height, activity level, and how much muscle your body contains.

The Performance Nutrition Calculator

Click the floating CALCULATOR tab on the right and enter your values in the Calorie Burn fields (PART 1-3). The calculator will determine how many calories you need daily in combination with your lean body mass and fat mass.

Bibliography

1. Arciero PJ, et al, Resting metabolic rate is lower in women than in men. J Appl Physiol (1985). 1993 Dec;75(6):2514-20. Retrieved from J App Physol.
2. Barrios, P, et al (2016). Reliability and criterion validity of self-measured waist, hip, and neck circumferences. BMC Med Res Methodol. 2016; 16: 49. Retrieved from US National Library of Medicine. 
3. Blake, J.S. (2014) Nutrition and You. New York, NY. Pearson. Retrieve source from Amazon.com
4. J. Hodgdon. and M. Beckett: Prediction of percent body fat for U.S. navy men and women from body circumferences and height. Reports No. 84-29 and 84-11. Naval Health Research Center, San Diego, Cal. 1984. Retrieved PDF source.
5. J. Hodgdon. and M. Beckett: Development of the DoD body composition estimation equations. Report No. 99-2B. Naval Health Research Center, San Diego, Cal. 1999. Retrieved PDF source.
6. Friedl, et al, Evaluation of anthropometric equations to assess body composition changes in young women, American Journal Of Clinical Nutrition, 73: 268-275, 2001. Retrieve from US National Library of Medicine National Institutes of Health.
7. Gastelu, et al, (2015) Specialist In Performance Nutrition: Weight Control, Fitness, and Performance Nutrition. International Sports Science Association. Retrieve from ISSA Website.
8. Kujawa, K., & Hodgdon, J. Comparison of circumference- and skin-fold based body fat estimation equations. Naval Health Research Center Technical Report No. 98-34. Retrieve PDF source.
9. Kujawa, K.I., Reading, J.E., Glover, W.L., & Hodgdon, J.A. Reliability of a four-compartment body fat estimation technique. Medicine and Science in Sports and Exercise, 31(5):S203, 1999. Retrieved from American College of Sports Medicine.
10. Kujawa, K.I., validity of navy circumference body fat equation in women of african-american, asian, hispanic, and filipina descent, Medicine & Science in Sports 7 Exercise, 34(5), S238, 2002. Retreived from Research Gate.
11. Kujawa, K.I., Comparison of cirumference-based and skinfold based body fat estimation equations, Medicine & Science in Sports & Exercise, 30(5), S277, 1998. Retrived from US National Library of MedicineNational Institutes of Health.
12. Shimokata H, et al, Aging, basal metabolic rate, and nutrition, Nihon Ronen Igakkai Zasshi. 1993 Jul;30(7):572-6. Retrieved from US National Library of Medicine National Institutes of Health.
13. Weltman, A., Accurate assessment of body composition in obese females, American Journal of clinical nutrition, 48(5): 1179-1183, 1988. Retrieved from The American Journal of Clinical Nutrition.
14. Tran, Weltman, Predicting body composition of men from girth measurements, Human Biol, 60:167, 1988. Retrieved from Research Gate.
15. ZiMian W., et al, Evaluation of Specific Metabolic Rates of Major Organs and Tissues: Comparison Between Men and Women. Am J Hum Biol. 2011 May; 23(3): 333–338. Retrieved from American Journal of Human Biology.