When should you stretch?
The answer to this question is you need to stretch when warm and stretch before you end your workout. You do not need to stretch when your body is cold and tight. You need to at least get your body slightly warmed up before you stretch. You can do this with a brisk walk or some calisthenics, or have a set time after you slowly start to stop and stretch. If you stretch your body when it is cold, you risk injuring yourself and your muscles not reacting properly. At the end of your workout, you need to spend a few minutes doing some stretches while your body is cooling off. Your body will have the tendency to seize up at the end of a hard workout. Make sure to budget some time in your workout to stretch at the end.
What muscles should I stretch?
When you think about stretching you need to think of the large muscles of your body and the tendons that connect all of them. A good rule of thumb is to begin either at your feet and work your way up or at your head and work your way down. You need to especially stretch your back and core, your quads, calves, and achilles tendons. If you are swimming you will want to stretch your neck and shoulders. Make sure to not over stretch and tear a muscle, but ease your stretching up to the point where you feel tension for a count of 5 and then back off. Repeat three to four times until you feel your muscle be comfortable.
How long should I stretch?
At the beginning of a workout, you will want to stretch each muscle group for a short time. You will want to pick a muscle, stretch it to tension for a count of 5, and the back off the tension. Repeat three to four times. At the end of your workout you will need to take a few minutes to stretch and cool down. If you have done a swim workout, you will want to stretch your shoulder, pectoral mucles and your neck along with your back and legs. If you run or bike, you will want to stretch your quads, back, calves, and achilles.
What type of stretches should I do?
There are many good stretches online that will graphically display to you some good stretches. You will want to have at least two different stretches for each major muscle group and then orate those stretches throughout your workouts. This will continually help your muscles to become more durable. Make sure to stretch while warm otherwise you might tear ligaments or tendons.