Pioneer Valley Youth Sports and Fitness Institute

the source for sound athletic advice

Metabolic Rate

As consistent summer like weather approaches, activity outside becomes more plentiful allowing one an endless amount of activities to participate in. Different activities require different energy demands. Depending on what one’s performance and fitness goals are different energy expenditure requirements are necessary. Most changes that occur in the human body during exercise are related to increase in energy metabolism largely within the contractile muscle. Having a better understanding of what energy metabolism is will help individuals comprehend their performance status.

There are basically two definitions of metabolism. A functional definition is that metabolism is the sum of all transformations of energy and matter that occur in the body, basically, everything that is going on in the body. An operationally definition, metabolism is the rate of heat production. By determining heat production, one can obtain a measure of metabolism, or metabolic rate.

The basic measurement of heat production is the calorie. Defined, a calorie is the heat required to raise the temperature of 1 gram of water 1 degree Celsius. Today, scientists’ measure heat production based on oxygen consumption or carbon dioxide production, this has shown to be a valid and reliable procedure for measuring metabolic rate. In addition to providing an estimate of metabolic rate, measuring metabolic rate can give an indication of the type of foodstuff being combusted such as carbohydrates (1 gram = 4 calories), fat (1 gram = 9 calories), and protein (1 gram = 4 calories); as a result, foodstuff combustion provides energy (ATP) needed to fuel the muscles in order for movement to occur. Knowing that we can measure (using graded or uphill exercise at submaximal levels) the respiratory response (oxygen in and carbon dioxide out) to exercise, we can determine one’s performance efficiency. Thus, one can make adjustments in their workout program to provide improvement in performance status.

For the most accurate measurement of metabolic rate, you can go into a University Human Performance Lab and get the test. You will generally use a treadmill or a stationary bike, and be given an oxygen mask to measure your oxygen exchange. You will also be connected with chest electrodes to measure your heart response. The main objective is to walk, bike, or run as the intensity is progressively elevated until it is not possible to go any longer.

Understanding what energy metabolism is and know how it helps performance will give you a better understanding of your performance efficiency. As n operationally definition, metabolism is the rate of heat production. By determining heat production, one can obtain a measure of metabolism, or metabolic rate. Factors such as age, health, activity levels, training programs, and genetics all affect metabolic rate; thus, efficiency values differ from individual to individual. Consult your physician before conducting the test. Seek the help of a qualified trainer to help you improve your metabolic rate if necessary.

To discuss resistance training and health/fitness programs please contact Len Haggerty at len@strideshpi.net.  Len Haggerty, MA, CSCS, YFS –Level 1 is a Sports Performance Coach operating STRIDES Performance & Wellness, Inc. in Northampton, MA. They provide an experience for youths, athletes, and adults of all ages and abilities to discover their potential.