A severe negative energy balance can lead to a decline in metabolism, decreases in bone mass, reductions in thyroid hormones, reductions in testosterone levels, an inability to concentrate, and a reduction in physical performance. Yet a negative energy balance does lead to weight loss.

A positive energy balance, in which energy intake exceeds expenditure causes weight gain, with 60–80 % of the resulting weight gain being attributable to body fat. In negative energy balance, when energy expenditure exceeds intake, the resulting loss in body mass is also accounted for by 60–80 % body fat.

Perfect Balance: If you end up with a 0 at the end of your energy equation, you’ve found a perfect energy balance. In this state, you won’t gain or lose weight. Perfect energy balance is for people who are in the weight maintenance stage of their weight loss journey.

A negative energy balance is when the amount of calories consumed is not sufficient for the body and leads to weight loss, whereas a positive energy balance is the opposite whereby calories are consumed in excess of the body’s requirements, therefore this additional energy is stored as fat by the body, leading to …

Energy intake includes 3 major macronutrient groups—carbohydrate, protein, and fat—and a smaller component from alcohol.

Energy requirement is the amount of food energy needed to balance energy expenditure in order to maintain body size, body composition and a level of necessary and desirable physical activity consistent with long-term good health.

The basic components of energy balance include energy intake, energy expenditure, and energy storage. Body weight can change only when energy intake is not equal to energy expenditure over a given period of time. Humans take in energy in the form of protein, carbohydrate, fat, and alcohol.

Total energy expenditure (TEE) consists of four components, i.e., the sleeping metabolic rate (SMR), the energy cost of arousal, the thermic effect of food or diet-induced energy expenditure (DEE), and the energy cost of physical activity or AEE.

NEAT are the little movements or tasks you do throughout the day, but are not considered moderate to vigorous exercise. On the other hand, EAT is the exercise-type activities like running, weight lifting, and so on.

Physical activity, defined as any bodily movement produced by skeletal muscles that results in energy expenditure, is derived from measurement of energy expenditure. BMR is a function of fat-free mass and total body water is a measure for fat-free mass. Thus, differences in total body water reflect differences in BMR.

What is the MOST critical limitation of direct and indirect calorimetry methods? They must be performed in a laboratory or special chamber. You just studied 25 terms!

The technique of direct calorimetry has several disadvantages. The structure is costly, requires complex engineering, and appropriate facilities are scarce around the world. Subjects must remain in a physically confined environment for long periods.

Indirect calorimetry systems estimate respiratory gas exchange as a surrogate for substrates consumed and produced during metabolism. This is done by one of 4 methods: confinement, closed-circuit, total collection, and open-circuit approaches.

Direct calorimetry measures the heat output by the subject, through direct observation inside a calorimeter. Indirect calorimetry measure heat by using the variable of O2 consumption and manufactured CO2. Indirect calorimetry gives a more feasible and accurate measure of heat or energy, compared to direct calorimetry.

Indirect calorimetry is the method by which measurements of respiratory gas exchange (oxygen consumption, V O 2 and carbon dioxide production, V CO 2 ) are used to estimate the type and amount of substrate oxidized and the amount of energy produced by biological oxidation.

In order to prevent under- and over-feeding and their related complications, it is important to accurately assess REE in individual patients and to ensure adapted nutrition support. IC is considered as the gold standard to this purpose and ideally any patients in whom energy needs are uncertain should be measured.

Factors affecting REE include: age • gender • body weight • body composition • weight loss • medications • exercise fever • disease • infection.

Currently, the most accurate clinical tool used to measure REE is indirect calorimetry, which is expensive, requires trained personnel, and has significant error at higher inspired oxygen concentrations.

Indirect calorimetry: one way to measure energy expenditure by measuring the respiratory exchange of O2 and CO2. This is called “indirect” calorimetry because heat production is more measured directly.