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Eating A Healthy Diet
Maintaining a healthy diet is the practice of making choices about what to eat with the intent of improving or maintaining good health. Usually this involves consuming necessary nutrients by eating the appropriate amounts from all of the food groups, including an adequate amount of water. Since human nutrition is complex, a healthy diet may vary widely, subject to an individual's genetic makeup, environment, and health. For around 20% of the planet's population, lack of food and malnutrition are the main impediments to healthy eating; people in developed countries have the opposite problem, and are more concerned about obesity.
Generally, a healthy diet is said to include:
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Sufficient calories to maintain a person's metabolic and activity needs, but not so excessive as to result in fat storage greater than roughly 30% of body mass. 2,000 is the recommended daily allowance of calories. (see Body fat percentage)
- Sufficient quantities of fat, including monounsaturated fat, polyunsaturated fat and saturated fat, with a balance of omega-6 and long-chain omega-3 lipids. 65 grams is the recommended daily allowance of fat.
- Maintenance of a good ratio between carbohydrates and lipids (4:1): four grams of the first for one gram of the second.
- Avoidance of saturated fat.
- Avoidance of trans fat.
- Sufficient essential amino acids ("complete protein") to provide cellular replenishment and transport proteins. (All essential amino acids are present in both animal and plant protein sources.)
- Essential micronutrients such as vitamins and certain minerals.
- Avoiding directly poisonous (e.g. heavy metals) and carcinogenic (e.g. benzene) substances;
- Avoiding foods contaminated by human pathogens (e.g. e.coli, tapeworm eggs);
- Avoiding chronic high doses of certain foods that are benign or beneficial in small or occasional doses, such as foods or substances with directly toxic properties at high chronic doses (e.g. ethyl alcohol); foods that may interfere at high doses with other body processes (e.g. refined table salt); foods that may burden or exhaust normal functions (e.g. refined carbohydrates without adequate dietary fibre).
Fresh vegetables are good for you!!
So is fresh fruit!!!
Exercise
Physical exercise is bodily activity that develops or maintains physical fitness and overall health. It is often practiced to strengthen muscles and the cardiovascular system, and to hone athletic skills. Frequent and regular physical exercise boosts the immune system, and helps prevent diseases of affluence such as heart disease, cardiovascular disease, Type 2 diabetes and obesity. It also improves mental health and helps prevent depression.
Types Of Exercise:
Exercises are generally grouped into three types depending on the overall effect they have on the human body:
Flexibility exercises such as stretching improve the range of motion of muscles and joints. Aerobic exercises such as cycling, walking, running, hiking, and playing tennis focus on increasing cardiovascular endurance. Anaerobic exercises such as weight training, functional training or sprinting increase short-term muscle strength.
Physical exercise is important for maintaining physical fitness and can contribute positively to maintaining a healthy weight; building and maintaining healthy bone density, muscle strength, and joint mobility; promoting physiological well-being; reducing surgical risks; and strengthening the immune system.
Exercise Benefits:
Frequent and regular aerobic exercise has been shown to help prevent or treat serious and life-threatening chronic conditions such as high blood pressure, obesity, heart disease, Type 2 diabetes, insomnia, and depression. Strength training appears to have continuous energy-burning effects that persist for about 24 hours after the training, though they do not offer the same cardiovascular benefits of aerobic exercises.
Both aerobic and anaerobic exercise also work to increase the mechanical efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training).
Not everyone benefits equally from exercise. There is tremendous variation in individual response to training: where most people will see a moderate increase in endurance from aerobic exercise, some individuals will as much as double their oxygen uptake, while others will never get any benefit at all from the exercise. Similarly, only a minority of people will show significant muscle growth after prolonged weight training, while a larger fraction experience improvements in strength.
Studies have shown that exercising in middle age leads to better physical ability later in life.
What Happens To Your Lungs During Exercise?
- The rate and depth of breathing increases
- A higher percentage of oxygen is extracted from the air available
- More blood flows through the lung capillaries to expel CO2 and absorb O2
What Are The Long-Term Effects Of Training On The Pulmonary System?
- Aerobic training such as swimming, jogging and cycling
- Increased capillary density around alveoli
- Increased endurance of respiratory muscles
- Increased respiratory muscle power
- Anaerobic training such as weights and sprinting
- A small increase in power of respiratory muscles
What Do These Training Effects Mean To The Athlete?
Aerobic training will bring about an improved blood flow (and therefore oxygen absorption) in the lungs. More blood flowing past the alveoli means more haemoglobin is potentially saturated with oxygen. Also, more CO2 can be expired. This increase in the supply of oxygen to the working muscles and an improvement in the endurance of the respiratory muscles means that the athlete can work much harder for longer periods. These pulmonary changes coupled with the muscular improvements in aerobic respiration mean the athlete will see a vast improvement in performance.
Below is a diagram of the lungs
Click on the link below to find out more about lungs.
http://science.nationalgeographic.com/science/health-and-human-body/human-body/lungs-article.html?source=G4103&kwid=about%20lungs|929422825
Below are some pictures of people doing different types of exercise.
Keeping Your Heart Healthy
From the moment it begins beating until the moment it stops, the human heart works tirelessly. In an average lifetime, the heart beats more than two and a half billion times, without ever pausing to rest. Like a pumping machine, the heart provides the power needed for life.
The heart weighs between 7 and 15 ounces (200 to 425 grams) and is a little larger than the size of your fist. By the end of a long life, a person's heart may have beat (expanded and contracted) more than 3.5 billion times. In fact, each day, the average heart beats 100,000 times, pumping about 2,000 gallons (7,571 liters) of blood.
Your heart is located between your lungs in the middle of your chest, behind and slightly to the left of your breastbone (sternum). A double-layered membrane called the pericardium surrounds your heart like a sac. The outer layer of the pericardium surrounds the roots of your heart's major blood vessels and is attached by ligaments to your spinal column, diaphragm, and other parts of your body. The inner layer of the pericardium is attached to the heart muscle. A coating of fluid separates the two layers of membrane, letting the heart move as it beats, yet still be attached to your body.
Your heart has 4 chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. The left ventricle is the largest and strongest chamber in your heart. The left ventricle's chamber walls are only about a half-inch thick, but they have enough force to push blood through the aortic valve and into your body.
It’s really important to keep you heart healthy. You can do this by eating a balanced diet and exercising regularly. Exercise is fun, try to do some every day!!!
Click on the link below for more information about your heart and ways to prevent heart disease.
http://www.bhf.org.uk/keeping_your_heart_healthy/default.aspx
If you click on the link below you can see an animated heart working!!!
http://www.platolearning.co.uk/demos/mss/demo_mss.php
Foods To Eat In Moderation
Some foods, whilst tasting nice, are not so good for you, so only eat these in moderation!!
For example, sugary foods e.g. cakes and biscuits and foods high in fat e.g. burgers.
A burger tastes nice but should only be eaten occasionally!!
Chocolate cake tastes great but remember it’s full of sugar!! Only eat it occasionally!!
Lots of sugar can also cause tooth decay!!
Reducing Salt (Sodium) In Your Diet
A key to healthy eating is choosing foods lower in salt and sodium. Most people consume more salt than they need. The current recommendation is to consume less than 2.4 grams (2,400 milligrams [mg] ) of sodium a day. That equals 6 grams (about 1 teaspoon) of table salt a day. The 6 grams include ALL salt and sodium consumed, including that used in cooking and at the table.
For someone with high blood pressure, the doctor may advise eating less salt and sodium, as recent research has shown that people consuming diets of 1,500 mg of sodium had even better blood pressure lowering benefits. These lower-sodium diets also can keep blood pressure from rising and help blood pressure medicines work better.
What Happens To The Body During And After Exercise
During exercise your heart needs to beat faster so that oxygen can be transported around your body. The oxygen supplies the muscles that are working hard. If the muscles are used for too long they become tired and start to ache.
During exercise you need more oxygen. Oxygen in breathed in from the air around us. During exercise, you breathe faster. When the body is working harder than usual, it becomes hotter and releases perspiration (sweat)!!
After exercise your muscles will feel tired. After resting, they will recover. It is important to make sure that exercise activity slows down gradually rather than just stopping. This helps your body recover more quickly.
After exercising the rate of your breathing slows down. Your muscles no longer need as much oxygen because they are not working as hard.
Click on the link below to find out more!!
http://cymru.digitalbrain.com/dbmaterial/web/learning%20objects/cymru/PrimaryScience-HealthyLiving/lo3/?backto&verb
Some Cool Links
Click on any of the link buttons below to find out lots of more cool stuff about exercise and keeping healthy.
Have fun!!!
Remember, as a member of the Science Bus Club you can ‘Ask Albert’ a question about any of the topics. So if you’re not already a member join today!!
