When it comes to running or doing an exercise for a longer period of time than what you are used to, you will need to increase your stamina. You should always eat healthy. Eating healthy foods will help you keep the energy you need to increase your stamina. However, the main thing you should do is to start with your activity like running at a comfortable speed, pace and amount of distance.
Each day, you should slightly increase your speed, pace or distance. This should help with your stamina, but then you should also take a few days a week to rest. You should do this routine every single day without rest. After doing this routine for several weeks, you should see an increase in your own stamina.
