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Weight management

Weight management is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Weight management rather than just read about it. In short: Weight management comprises behaviors, techniques, and physiological processes that contribute to a person's ability to attain and maintain a healthy weight. Most weight management techniques encompass long-term lifestyle strategies that promote healthy eating and daily physical activity.

Weight management — main illustration
Weight management — illustration

Key takeaways

  • Weight management belongs to science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Weight management to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Weight management from memory before moving on to harder problems.

Reference excerpt

Weight management comprises behaviors, techniques, and physiological processes that contribute to a person's ability to attain and maintain a healthy weight. Most weight management techniques encompass long-term lifestyle strategies that promote healthy eating and daily physical activity. Weight management generally includes tracking weight over time and identifying an individual's ideal body weight. Weight management strategies most often focus on achieving healthy weights through slow but steady weight loss, followed by maintenance of an ideal body weight. However, weight neutral approaches to health have also been shown to result in positive health outcomes. Understanding the basic science of weight management and strategies for attaining and maintaining a healthy weight is important because obesity is a risk factor for development of many chronic diseases, like Type 2 diabetes, hypertension and cardiovascular disease.

Key factors There are many factors that contribute to a person's weight, including: diet, physical activity, genetics, environmental factors, health care support, medications, and illnesses. Each of these factors affects weight in different ways and to varying degrees, but health professionals most often stress the importance of diet and physical activity because they can be affected by conscious behavior modification. Attaining a healthy weight involves recognition of general techniques such as portion sizing, self-monitoring, and daily diet consistency. Once this healthy weight has been attained, maintaining this stable weight additionally involves physical activity and control of an individual's environment and eating patterns. Furthermore, healthcare support in the form of primary care medical supervision and following up over time has been shown to be helpful for long-term weight management. The following is a review of some of the key components of weight management in humans.

Energy balance The science behind weight management is complex, but one of the key concepts that governs weight management is Energy Balance. Energy Balance is the phrase used to describe the difference between the number of calories a person consumes and the number of calories that same person expends (i.e., burns) in a given time period. There are three possible scenarios when it comes to the energy balance equation:

Calories consumed (food, drink) = Calories expended (basal metabolic rate, physical activity, thermogenic effect of food, acute illness) Outcome: Weight remains unchanged Calories consumed > Calories expended Also known as Positive Energy Balance Outcome: Weight increases Calories consumed < Calories expended Also known as Negative Energy Balance Outcome: Weight decreases The calories a person consumes come from food and drink intake. The calories a person expends comes from their basal metabolic rate and their daily physical activity. The human body is very good at maintaining a neutral energy balance, particularly with a diet composed of fruits, vegetables, and meats so that calories consumed do not substantially exceed calories expended in a given time period and vice versa. This energy balance is regulated by hormones like Leptin (suppresses), Ghrelin (stimulates), and Cholecystokinin (suppresses) which either suppress or stimulate appetite.

Diet The quantity of food and drink consumed by an individual may play a role in weight management, as may the types of food and drink a person consumes. For example, intake of sweetened drinks such as sodas or juices can lead to increased energy intake that is not neutralized by a decrease in accompanying food intake. Increased portion sizes may also lead to increased energy intake. Food categories such as intake of proteins, carbohydrates, and fats are all important to consider when managing weight. It is also important to have control and understand how certain foods may affect the human body.

Physical activity

Physical activity can be related to a person's professional activities, non-work related daily activities like walking or cycling, or it can be in the form of activities such as recreation or team sports. The specific type of activity can be tailored to populations such as children, pregnant women, and elderly adults. Tailored activity to one's fitness level also encourages the body to heal properly and prevent any injuries as a result of exercise. Physical inactivity leads to less energy expenditure and is a factor that impacts obesity rates in both children and adults. Physical inactivity has become a worldwide concern since inactivity also elevates the risk of heart disease. With a regular active lifestyle it can reduce the risk for noncommunicable diseases like diabetes, heart disease, and dyslipidemia (high cholesterol). Physical activity not only reduces the risk of noncommunicable diseases, but it also can benefit the body such as improving sleep patterns, reducing both anxiety and depression, and of course, helps weight loss and weight management.

Basal metabolic rate Basal metabolic rate (BMR) is one of the main components of a person's daily energy expenditure. It is defined as the amount of energy that is expended during a given amount of time by a person at rest. This energy at rest is used to pump blood throughout the body, maintain proper brain function, break down toxins, and ensure other bodily functions. Technically speaking, BMR is the energy the body expends during the following specific conditions: immediately after waking up, while in a resting state, and after fasting for 12–14 hours. Sometimes the term Resting Metabolic Rate (RMR) is used in place of BMR, but RMR is not solely measured under the previously listed stringent conditions and it is about 10% more than BMR. The BMR is directly proportional to a person's lean body mass. In other words, the more lean body mass a person has, the higher their BMR. BMR is also affected by acute illnesses and increases with burns, fractures, infections, fevers, etc. It can be measured via direct and indirect calorimetry. However, it is also possible to approximately estimate BMR using several equations that factor in a person's age, sex, height, and weight. Some of the most popular and accurate equations used to calculate BMR are the original Harris-Benedict equations, the revised Harris-Benedict equations, and the Mifflin St. Jeor equation. The original Harris-Benedict Equations are as follows:

… excerpt ends here. Continue reading the full article.

Illustrations

Weight management: Nutrition is an important part of maintaining a healthy body weight.
Nutrition is an important part of maintaining a healthy body weight.
Weight management: An image that shows nutrition label information including calorie amounts
An image that shows nutrition label information including calorie amounts
Weight management: Running on a treadmill is one form of physical activity that can be done at home or at a gym.
Running on a treadmill is one form of physical activity that can be done at home or at a gym.
Weight management: Waist circumference may be used as an alternative method to assess weight.
Waist circumference may be used as an alternative method to assess weight.
Weight management: Fruits and vegetables are considered staples of the Mediterranean diet.
Fruits and vegetables are considered staples of the Mediterranean diet.

Worked examples

Example 1 — a first encounter with Weight management

Start with the simplest possible case. Write down what Weight management claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Weight management before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Weight management ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Weight management

In research
Weight management appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Weight management in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Weight management is common in secondary-school and first-year university syllabi. It links to neighbouring topics Weight loss, so understanding it makes those chapters shorter.
In everyday life
Look for Weight management outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Weight management in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Weight management means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Weight management out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Weight management in simple terms?

Weight management comprises behaviors, techniques, and physiological processes that contribute to a person's ability to attain and maintain a healthy weight. Most weight management techniques encompass long-term lifestyle strategies that promote healthy eating and daily physical activity.

Why does Weight management matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Weight management?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Weight management.

Tags

  • Weight loss

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