Do not push your body during beginner triathlon training
It is imperative that when you start your beginner triathlon training that you do not push yourself too hard in the beginning of your training regimen. When you push yourself too hard you risk the chance of succumbing to injuries at a faster rate.
It would behoove you when engaging in beginner triathlon training to gradually increase your speed and gradually increase the distance that you are going to be traveling. If your body feels like it is going to give up during your training method, trust your body and take a break then you may resume your training shortly thereafter.