Welcome to the forum and well done on getting started.
This guide to the plan is essential reading healthunlocked.com/couchto5... and explains the recommended easy conversational pace...........if you are out of breath, you are going too fast.
Slowing down will also reduce the impact and be kinder on your body.
Go slower. At this stage I would aim for 4.5-5 mph. You can build speed later. Make sure you are fully hydrated the day before and ensure you are doing appropriate stretches before and after. Have patience and it will come. Good luck.
(1) Out of breath is classic sign that you're going MUCH too fast.
(2) Using the treadmill, you have the PERFECT tool to control your speed... knock that speed right down to a SLOW jog - even if's slower than your brisk walking pace.
(3) Weeks 1 and 2 will not have improved your aerobic fitness significantly for you to notice. You will notice those improvements as your progress through the program .... but the key is to progress! And the key to progressing is ... going at the right speed/pace.
S L O W D O W N !!!
(4) Speed wise... you should aim to finish each session feeling like you could carry on. You're aiming for a 'conversational pace' - one at which you can comfortably talk at.
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