Science Year 3 Animals incl Humans Block 3

Science - Year 3 Animals incl. Humans – Block 3 AH Keeping Healthy Session 5 Power. Point © Original resource copyright Hamilton Trust, who give permission for it to be adapted as wished by individual users. We refer you to our warning, at the foot of the block overview, about links to other websites.

We use our muscles for everything we do!

When we do sport regularly it builds up the strength in the muscles we are using. Sports people do exercises to build up strength in the muscles they need.

When our muscles are working hard, they need more oxygen than usual. Have you noticed that you breathe faster and more deeply when you exercise?

Oxygen is in the air that is all around us. But how does it get to our muscles? When we breathe in, air fills our lungs. Our lungs are two spongy bags inside our ribcage. Place your hands over your lower ribs and take a deep breath in. What can you feel? Your ribs move upwards and outwards as your lungs fill up with air.

Wind Pipe Lungs Your wind pipe divides in two and takes the air to your lungs. When you take a deep breath, your lungs expand rather like a balloon that is being inflated

Your body breathes by using a powerful muscle called the diaphragm. Diaphragm When it is relaxed the diaphragm is curved upwards like this. When you breath in, the diaphragm contracts which pulls it downwards, creating more space in the chest.

This diagram shows the same thing from the side. Here the diaphragm is relaxed and there is not much space in the chest, so air is forced out of the lungs. Here the diaphragm has contracted to make more space in the chest, so air is drawn into the lungs.

You can try this out using an empty plastic drinking bottle. If you squeeze the bottle, air is pushed out because there is less space for air in the bottle. If you stop squeezing and let the bottle return to its usual shape, air will be sucked back inside to fill the extra space. Put your hands on your lower ribs once again and take a deep breath. Imagine your diaphragm pushing downwards to make more space in your chest, allowing your lungs to fill with air. Now breathe out slowly, your diaphragm is relaxing (returning to its domed shape). It is squeezing air out as there becomes less and less space in your chest.

Your lungs take oxygen from the air and transfer it to your blood. Once the oxygen is in your blood, it can travel around your body to all the places where it is needed. Your muscles cannot work without oxygen. The harder they work, the more oxygen they need!

This is why you need to breathe faster and more deeply when you exercise!

The diaphragm is a muscle and like other muscles you can build up strength in it by using it regularly. Singers build up strength in their diaphragm by working on their breath control with regular practice, for example by taking deep breaths in and breathing out in a slow controlled way. They need very good breath control to hold long notes.

Singing takes a lot more breath than speaking and good posture is really important. Try keeping your shoulders relaxed and still whilst taking a deep breath from your diaphragm. Breathe in over a count of 3 and sing an “Ahhhh” sound steadily over a count of 11. If you find it easy, try again over a count of 13 or even 15. Remember – The more you practise, the better you get. This is because you are making your diaphragm stronger!

It’s not just singers who need to build up strength in their diaphragm!