The following duration of interval is typically ridden.

Short intervals typically last between 15-90 seconds, medium intervals between 3-5 minutes, normal intervals between 8-10 minutes and the long intervals, which can last from anything from approx. 10 to (45-60) minutes depending on the purpose.

Intervals of more than 5 minutes are typically the ones you should introduce a little later in a training course and ought to have a duration of 8-10 minutes of the same intensity. And for the elite up to hour long intervals.

Before an interval is set in motion, you should be clear exactly how far or how much time this interval lasts. It is clearly an advantage to know this in advance, so you can gear yourself up mentally for the job at hand. After this you should set your tempo and intensity that you are able to keep during the entire interval in question. If you do not handle the same intensity during the whole interval in question you ought to turn down your intensity a little next time.

Attention! It is physiologically proven via tests on athletes that you can improve both your time trial qualities and increase your max capacity by training approx. 6 intervals of approx. 5 minutes during a 500 km training week.

In other words, the short intervals are not a condition in order to increase your physical capability, but the short intervals can help you increase your speed when sprinting and the ability to close the gap to a group of racing cyclists in front of you, which is a typical competitive situation.