Space out the training runs throughout the week with at least one day off between runs to give your muscles time to recover and repair. Focus on gradually increasing the time or distance that you are running and leave the faster times until your bones are stronger and your body fitter. Your muscles actually need a day of rest to repair and rebuild. If you run every day you actually won’t see as much improvement as when you rest.
Each of your training sessions should take between 20 and 40 minutes each day, three days per week. Using this 5k beginning running program will get you fit and improve your cardiovascular fitness. Runners who do more than this are usually interested in more than fitness.