Your muscles ache from a good stretch. This is quite normal and is part of the process. Stretching has seemingly been with us and particular with athletes since the beginning of time. A very key point to good stretching is to hold the stretch for at least seventeen seconds. This is a pearl of wisdom gleaned from a ballet teacher a few years back. She said that any stretch under 17 seconds was just not effective. The 17 second rule is exceeded in the high intensity Bikram's yoga where stretches are held for about 30 seconds. Don't forget the high level of heat that is used in Bikram's to extract that last little bit of stretch out of your muscles. An interesting twist that is not necessary to gain benefits from stretching. But, it can't hurt, right? So what kind of benefits can you expect from stretching? That's an easy one. Have you ever seen the movie, Blood Sport? Did you know that Frank Dux could truly stretch his body to the extreme. The actor that played him was quite elastic as well. Great elasticity is also something you might see in well trained Spetsnaz(Russian)agents. They often work out with Russian kettlebells too. They are for superior strength gains and the ability to withstand ballistic shocks. Why are stretching and flexibility considered important to these people? Stretching gives one the ability to have explosive power available at one's fingertips without the need to warm up. Of course most of us are not martial artists or agents. But, you'll be happy to know there are plenty of other benefits. Let me give you an example. After learning to sit in the full lotus position for long periods of time, my ankles became very flexible. One day I was walking along and my left foot fell into a pothole. This mishap pushed my ankle sideways to about 90 degrees from it's normal position. Amazingly, this didn't even hurt, not one bit. If my ankle hadn't been so flexible, I may have suffered a sprained ankle. At the very least, it would have hurt for days. Key point: stretching helps us to avoid injuries. Not only that but if you do have a muscle, tendon or ligament injury it should heal faster, theoretically speaking. Stretching actually grows the ligaments, tendons and muscles being stretched. They really grow longer over time. Check with your physician before undertaking any type of exercise, including stretching.