It can be said there are three main types of stretching. These include static, dynamic and Proprioceptive Neuromuscular facilitation (PNF) stretching.
How are they performed?
To perform static stretching, you take a muscle to the point where tension is felt, and hold this position for a specific amount of time, usually 30 seconds to 1 minute.
PNF stretching is similar to static stretching where you take a muscle to the point of tension, however a muscle contraction is added in at this point. The muscle contract is usually held for 5 to 10 seconds, followed by a static stretch into a new range that the contraction afforded.
Dynamic stretching involves moving a joint through its full range of motion with speed, usually to the point where tension is felt, for example a leg swing.
What effect do they have on you?
In the short term, they all are able to increase your range of motion, with varying level of effectiveness. Given the same time spent stretching, PNF stretching gives you the greatest increase in range of motion, followed by static and dynamic.
However, in terms of performance and muscle force output, both PNF and static stretching decrease your athletic ability. In fact, PNF causes the biggest decrease in many aspects including force output, power production, reaction time, sprinting and jumping. Not to worry though, these effects wear off after 24-48 hrs.
Interestingly, dynamic stretching has actually been shown to increase performance variable while still giving a noticeable gain to range of motion, making it the perfect addition to a warm up.
In the long term, stretching will increase the length of tissue giving a more permanent range of motion increase.