If you aren't tailoring your warmups to match the mechanics of application and technique you may be wasting an opportunity to make more progress in less time. Whether you are teaching a class or just preparing for your own training there is a lot more you can do with a warmup than just touching your toes and doing a few lame jumping jacks.
A good warmup will increase the heart rate, speed blood flow, increase the respiration rate, raise muscle temperature, and stimulate fluids to lubricate the joints. It should start with simple, multi-joint movements that do not require much coordination. The intensity should start low and gradually increase. You will know that your warmup is working when your students start sweating. I usually start my classes with footwork or some other full body movement.
The primary goal of a warmup is to prevent injury by preparing the body for more intense training, but it will also make the body more responsive and efficient in its response to nerve signals. This is where it really affects performance. After a simple five minute warmup with basic exercise and maybe some dynamic stretching / joint mobility exercises, you should then take this opportunity to continue to warmup with movements that are more specific to the motor patterns used in the application of technique. This approach is nothing novel. It is used in sports training, but it is the key to getting more out of the session.
I use two approaches in my class warmups. Both incorporate motor patterns related to application, but one is general to and the other is more specific to the coming lesson.
The General Approach
In the general approach, I will use movements that are core basics in our system that should be practiced frequently regardless of the student level. This would include things like fundamental footwork and frequently used striking combinations. This is a good approach if the students attending will be separating into groups by level to work on different material for the rest of the class. This situation is more common in our local ongoing classes. Each week, I rotate through a different set of basics, but repeat some of the most fundamental elements each week.
The Specific Approach
The specific approach is best for streamlining instruction, and I prefer to use it if the situation allows. If everyone will be learning the same lesson, then I will incorporate very specific movements that are a part of the upcoming lesson in the warmup. This approach is very simple, but it makes a difference. Doing this makes for a more seamless progression from warmup to coordination training and the following lesson. It also saves precious training time. I want to accomplish as much as possible in the time we have available. In a one hour class, our warmup session lasts 15 to 20 minutes, but in that time, we not only warmup, we get some quality repetitions that will make learning the upcoming drills and techniques in the lesson easier.
Grand Tuhon is truly a master at this. He may lead students through a warmup drill that leaves everyone saying, "What the hell are we doing?" Twenty minutes later, everyone is marveling at how much better they are able to move because of the exercise. It is really a sort of moving sculpture, wherein you are conditioning the right movement and patterns. There is both a science and an art to it.
When I am teaching a seminar or camp, I want to leave the biggest impact I can with that little amount of time. I want to develop skills in the students right then. I want to see improvement during the session that students will retain. Usually the biggest impact will be in developing better mechanics, better attributes and better understanding.
After the initial warmup, I include a more extensive coordination training session. I put a lot of thought into what specific coordination exercises I include, and I make note of what worked the best to meet my training objectives for the lesson. I use the warmup as a way to remind the students of the proper mechanics while still warming them up. I start with something that is simple and likely familiar to most. I can then diagnose and address any potential movement issues I need to fix before moving on.
When I do this with more experienced students, I think of it as refreshing the muscle memory. Students may have trained the movements in the past, but I want them freshly charged and ready to go. I shake the dust off those mechanics, and I prime the students with a movement pattern that will answer questions that have not yet been asked. I do this to create a reference to a movement pattern, then structure my lesson so that pattern will resurface more easily when needed. For newer students, I may simply help them see that the movement in the technique relates to the warmup. For advanced students and instructors, I may set up a connection that they will discover when drilling.
In any case, this method makes for an easier transition to the material contained in the upcoming lesson and helps me get more out of the students with the time we have together. It also makes it a lot more interesting for me.