Exercise Physiology

Why Warm-Up and Cool-Down

� Exercise Physiology — Why Warm-Up and Cool-Down Are Non-Negotiable: Body Temperature, Blood Flow, and Safer PE Lessons

Hello, this is Young-in teacher! :)

In a busy PE period, it’s easy to shorten or skip warm-up and cool-down while trying to “cover the content.”
Warm-up routines are now fairly well established in elementary PE, but cool-down still isn’t consistently built into lessons in a systematic way.

However, starting an all-out sprint when the body is still “not ready,” or flopping straight down onto the floor the moment the activity ends is actually quite risky in terms of body temperature and blood circulation.

Today, let’s look at why warm-up and cool-down are not optional but essential, and explore the science behind them!

1️⃣ The Core of Warm-Up — Raising Body Temperature & “Opening the Pathways”

The main goal of a warm-up is to shift the body from “daily mode” to “exercise mode.”

� Raising muscle temperature

Light jogging or simple step movements increase body temperature. Warm muscles behave like flexible rubber bands — they stretch and contract more smoothly, and the risk of injury drops significantly.

⚙️ Lubricating the joints

When students swing and circle their arms and legs, it’s like coating their joints with lubricant (synovial fluid). Stiff joints get ready to move more freely.

⚡️ Waking up the nervous system

Rhythmic movements or reaction games speed up signal transmission between the brain and muscles. Thanks to this, students can react more quickly and move more sharply during the main activity.

For students, you can put it simply:

“Warm-up time is when we warm up the muscles, loosen the joints,
and switch on the sleeping ‘sports nervous system’!”

2️⃣ The Core of Cool-Down — Safely Returning Blood Flow to Normal

Right after exercise, the heart rate and blood flow are still in full “exercise mode.” What happens if students suddenly stop and just lie down or sit on the floor?

� Preventing dizziness (redistributing blood flow)

During exercise, the leg muscles work like a pump, helping push blood back up to the heart.
If they suddenly stop moving:

Blood can pool in the legs,

Less blood reaches the brain and heart,

Students may feel dizzy, light-headed, or nauseous.

� Cleaning out waste products

After intense activity, muscles are full of by-products like lactate. If students move into light jogging or gentle walking plus stretching, and we gradually slow down circulation:

Blood flow carries these substances to the liver and heart,

They are broken down and cleared more efficiently.

So, cool-down is not “just stretching.” It’s a process of helping the body land safely back into “daily mode.”

3️⃣ A 3-Step Routine You Can Use in Any Lesson (Template)

Once you set this as a fixed routine, you can apply it to almost any PE unit.

① 3 Steps of Warm-Up

Raise body temperature Light jogging, marching, or on-the-spot running (warming the whole body)

Mobilize the joints Circling wrists, ankles, shoulders, knees (dynamic stretching)

Connect to the main activity If it’s soccer: light passing in pairs If it’s basketball: dribble tag or simple dribble games

→ A “preview” that links directly to the main skill

② 3 Steps of Cool-Down

Gradually slow down Running → fast walking → slow walking (Active cool-down to gently bring heart rate down)

Static stretching Stretch the main muscle groups used that day Hold each stretch for about 10–20 seconds while exhaling slowly

Psychological closure Ask: “How did your body feel today?” Have students briefly share their sensations or a one-word reflection

� Classroom Application – Young-in Teacher’s TIP! (Use it right away)

✅ Tip ① Give meaning with “Temperature & Pulse Check”

Before and after warm-up:

Have students measure their wrist pulse for 15 seconds, or

Place a hand on their cheek or chest and feel the warmth and heartbeat.

Then say:

“How does it feel? Is your heart beating faster, is your body warmer? Now your body is ready to exercise!”

This helps students see warm-up not as “extra time,” but as a switch that turns their body on.

✅ Tip ② Turn Cool-Down into “Thank-You Time for the Body”

While stretching, add some short guiding phrases:

“Let’s say thank you to the leg muscles that worked so hard today.”

“Feel how far your breath goes down into your body as you take a deep breath.”

This not only helps physical recovery, but also gently calms students’ excited minds at the end of class. The words they say to themselves during this time can be surprisingly powerful.

� In Closing

Warm-up and cool-down are not “leftover minutes” that eat into teaching time.
They are the opening and closing of the lesson that help students:

avoid injuries, and

perform at their best possible level.

In today’s PE class, how about fully enjoying the process of warming the body up together
and then cooling it back down calmly with your students?