Related Experiment Video

Updated: Aug 14, 2026

Body Composition and Metabolic Caging Analysis in High Fat Fed Mice
10:28

Body Composition and Metabolic Caging Analysis in High Fat Fed Mice

Published on: May 24, 2018

Activity, energy metabolism and postnatal age relationship in low-birth-weight infants

I Rubecz, J Mestyán

    Acta Paediatrica Academiae Scientiarum Hungaricae
    |January 1, 1975
    PubMed

    Insights

    Premature infants increase spontaneous activity and heat production with age. This suggests the energy cost of activity rises as premature infants mature postnatally.

    Area of Science:

    • Neonatal physiology
    • Infant development
    • Metabolic studies

    Background:

    • Low-birth-weight infants, including premature and small-for-gestational age infants, exhibit unique physiological challenges.
    • Understanding their energy expenditure and metabolic adaptation is crucial for optimal care.

    Purpose of the Study:

    • To investigate the relationship between spontaneous physical activity and heat production in low-birth-weight infants.
    • To determine how this relationship changes with increasing postnatal age.

    Main Methods:

    • Studied 30 low-birth-weight infants.
    • Monitored activity levels and heat production.
    • Analyzed correlations between activity intensity and metabolic output over time.

    Main Results:

    • A close correlation was observed between infant activity levels and heat production.
    • Older infants showed higher spontaneous activity and greater variability in heat production.
    • The energy cost for a given activity intensity increased with postnatal age.
    • Maximum oxygen consumption also increased with postnatal age.

    Conclusions:

    • Spontaneous activity and heat production in low-birth-weight infants are closely linked.
    • Maturation with increasing postnatal age enhances both activity and the efficiency of heat production.
    • These findings highlight the dynamic metabolic adjustments occurring in growing premature infants.

    More Related Videos

    Measuring Mitochondrial Electron Transfer Complexes in Previously Frozen Cardiac Tissue from the Offspring of Sow: A Model to Assess Exercise-Induced Mitochondrial Bioenergetics Changes08:04

    Measuring Mitochondrial Electron Transfer Complexes in Previously Frozen Cardiac Tissue from the Offspring of Sow: A Model to Assess Exercise-Induced Mitochondrial Bioenergetics Changes

    Published on: August 16, 2021

    Determining Basal Energy Expenditure and the Capacity of Thermogenic Adipocytes to Expend Energy in Obese Mice06:57

    Determining Basal Energy Expenditure and the Capacity of Thermogenic Adipocytes to Expend Energy in Obese Mice

    Published on: November 11, 2021

    Related Concept Videos

    Activation Energy01:26

    Activation Energy

    Activation energy is the minimum amount of energy necessary for a chemical reaction to move forward. The higher the activation energy, the slower the rate of the reaction. However, adding heat to the reaction will increase the rate, since it causes molecules to move faster and increase the likelihood that molecules will collide. The collision and breaking of bonds represents the uphill phase of a reaction and generates the transition state. The transition state is an unstable high-energy state...
    Energy Budgets and Reproductive Strategies00:51

    Energy Budgets and Reproductive Strategies

    Organisms must balance energy intake with the energy required for growth, maintenance, and reproduction. These trade-offs result in a variety of survivorship and reproductive strategies, including semelparity and iteroparity. Semelparous species reproduce only once in their lifetime, often investing most available resources into that single reproductive event. Iteroparous species, by contrast, reproduce multiple times over their lifetimes, typically allocating fewer resources to any single...
    Energy Balance01:19

    Energy Balance

    The human body gets energy from the three macronutrients: carbohydrates, proteins, and fats. Energy is released when the chemical bonds in the organic compounds present in the food are broken down. The energy content of food is measured in kilocalories (kcal), defined as the amount of heat required to raise the temperature of one kilogram of water by one degree Celsius. This value is determined by measuring the temperature change of the water surrounding a calorimeter after the complete...
    Metabolic Rate01:25

    Metabolic Rate

    The human body is a powerhouse of energy, with every cell performing numerous functions that require energy. This energy production and consumption is measured by the metabolic rate, which quantifies the total heat generated by all the body's chemical reactions and mechanical work. This measurement helps to determine the rate of kilocalorie (kcal) consumption needed to fuel all ongoing activities.
    The Basal Metabolic Rate (BMR) measures the energy expended at rest.
    Several factors influence the...
    Inborn Errors of Metabolism01:20

    Inborn Errors of Metabolism

    Phenylketonuria (PKU) is a protein metabolism disorder characterized by high blood levels of the amino acid phenylalanine. This results from a mutation in the gene responsible for phenylalanine hydroxylase, an enzyme that converts phenylalanine into tyrosine. When this enzyme is deficient, phenylalanine builds up in the blood, leading to symptoms such as vomiting, rashes, seizures, growth deficiency, and severe mental retardation. An early diagnosis and a diet restricting phenylalanine intake...
    Pharmacokinetics in Pediatric Patients: Drug Distribution01:17

    Pharmacokinetics in Pediatric Patients: Drug Distribution

    Drug distribution in the pediatric population exhibits unique challenges and considerations due to the physiological differences between children, particularly neonates and infants, and adults. A crucial aspect of pediatric pharmacology is understanding how these differences impact the pharmacokinetics of various drugs, necessitating age-specific dosing strategies to ensure efficacy and safety.Neonates and infants have a higher total body water content, ~75%–90% of their body weight, compared...