When you do any job with your body it takes time wake up the nervous system, which is the communication system between all your body systems.
The role of warm up before exercise is to wake up nervous system which tells to the brain that attention to muscles is needed. When you start to move you oxygen need increases and that’s why your pulse and breathing speed up.
You start to breathe more oxygen and trough the blood it comes to muscles and all cells involved in exercises.
If you don’t warm up before exercises than your body is cold and not prepared for exercise and could happen following:
- You suddenly jump, squat etc., there is more need for oxygen by muscles and your brain don’t get enough oxygen (for short time, because brain is always major importance) and that’s why you feel dizzy. This situation quickly disappears because following happens:
- Brain send command “Breathe, I need more oxygen”. And you start breathe faster, your pulse goes up cause more heart beats, more oxygen and suddenly you feel yourself breathless and with tachycardia.
- Injury is another bad possibility.
If you skip warm up before workout, all above happens but our bodies are strong and quickly adapts. But sometimes bad consequences can happen.
Now watch warm up and download links are under the video.
Windows users click here to download warm up video
Mac users click here to download warm up video
My advice is always warm up, even short warm up – 2-3 minutes is better than 0 warm up 
Warm uped,
Rumi