Unfortunately if you're attacked unexpectedly you don't have time to warm up. Training should always be as realistic as possible, so you should train cold as much as possible if you are training for self defense purposes. This carries a risk of injury and should be undertaken very carefully. You need to slowly and gradually test your limits. You need to do this to prevent injury. But you also need to instinctively know what your body is capable of in a realistic situation. Regular exercise and stretching, martial arts - and especially fight training such as MMA or Muay Thai - will help keep you in the right sort of shape.
To defend yourself you need the following - in order of importance:
If you practice maintaining a state of awareness then you can avoid the situations that lead to violence and death. Make sure you know what's going on around you, who is where and who is doing what and why, at all times. It should be habit. Instinctive. A way of life. People who have cultivated their awareness sometimes seem cold and distant in social situations when violence threatens. Stay close to these people, they might save your life. They will spot trouble long before you do. When the broken bottle slashes their way they will be expecting it. They will be prepared. They will act, not re-act. It might look as though they have incredibly fast reflexes. Actually they have probably been aware of a developing situation and preparing themselves for several minutes. This is the state of awareness you need to cultivate. Tune in to other people's state of awareness, their body language and any warning signs. In nature animals are often warned of danger by the warning cries of birds or other animals. We are animals too and we have powerful survival instincts that can be cultivated. If you don't cultivate them then they will fade away. 'Use it or lose it' is the rule when training your body and mind.
You need to know the pressure points that work best in self defense. You can learn these quickly and easily on the DVD. You need to know what sort of attacks are most likely to come at you and how to defend against them. Training in MMA and/or Muay Thai are the best ways to gain this knowledge and develop it into instinctive reactions over time.
It is no use applying force to somewhere that isn't easily damaged, so you need to learn to fight using pressure points.
But equally it is no use knowing exactly where to strike unless you are capable of hitting the place you are aiming for - and this may be on a moving target. You can train with a sparring partner, make marks on a free-swinging punch bag, or strike a tennis ball to help you develop accuracy. You have to sacrifice some power for accuracy. But the more you train the more you will be able to strike with power and accuracy. When sparring or training with a bag, or any other kind of training, always visualise the situation, the attack, the pressure point targets that you would be trying to strike in a real-life self defense situation. Visualisation is a good second best to really realistic training if that is not practical.
You need to familiarise yourself with the effects of fear and learn to deal with them. Practice controlling your breathing. Make sure you are not holding your breath. Air is vital in combat. Familiarise yourself with fighting in realistic and difficult situations: in the dark. On the ground. In restrictive clothing.
A powerful blow to a vulnerable pressure point will never connect if the attacker sees it coming. You need to practice delivering fast strikes. You also need to avoid telegraphing your intent beforehand (filming and watching your training will help with this) or the vital advantage of speed is reduced. Thing SAS: speed, aggression, surprise. You might use deception or distraction, such as asking a random question to confuse your attacker and buy a moment of time while their mind is elsewhere. This feeds back into knowledge.
Some pressure points are more vulnerable than others. See the DVD. But if you strike with the force of a falling feather then you are going to do little damage. Once you have developed accuracy and speed, increase the power, but always maintain the speed and accuracy. They are more important than power. Real power is delivered not just with muscles and weight but also by rotating the hips and shoulders, the force travelling along a rigid line of power from the floor to the point of impact that hardens at the moment of impact. This takes a lot of practice but you can achieve good results with minimal training if you utilise the other principles above.
The amount of force you deliver is directly related to how much you weigh. Aim to develop muscle rather than fat. It is heavier for one thing. When developing muscle always make sure you are training the new muscle tissue to deliver speed. A boxer may keep their weight down for weigh-in. That is because weight is power and you should not be looking to lose healthy muscle weight for self defense purposes. That said, being large and muscle-bound offers little advantage beyond a certain limit - especially if you are slow.
You need to be able to sustain the fight for at least a couple of minutes. Most attacks are over in seconds and you are unlikely to get to deliver more than two or three strikes. But there may be two or three attackers. Or your opponent may be very hard to eliminate - especially if you are tired or injured and hence weaker than usual. Stamina is an important component of general fitness and should be cultivated.
9) Anatomical armour
Some of your body's vital organs are to some extend protected by slabs of muscle. Most significantly your abdominal muscles play an important protective role and should therefore be developed and conditioned using sit-ups (sometimes with a twist), crunches (sometimes with a twist) and leg-raises. Knee strikes are a vital part of your arsenal and practicing these has some benefit for your abdominal muscles too.
Big is not always best. Large muscles developed using slow movements are usually slow muscles not suited for the fast, explosive movement you need for striking. Weight training for self defense should be as realistic as possible. Try to mimic striking movements and add difficulty, weight, or resistance to those movements to increase their power.
Weight training for self defense does not necessarily
In a fight you may be injured or tired. Your attacks may have terrifyingly little effect. Get used to this disconcerting feeling with full contact sparring. And train until you are totally exhausted. Only then judge what you are capable of. It is a sobering experience and one you should repeat again and again. This is the real base-line of your abilities. Get to know it.
If you want to take your training to even higher levels of realism you might consider adding adrenaline to the mix. Your body will be flooded with adrenaline during an attack and this will have significant physical impacts. For example you may be slightly faster, stronger and less prone to injury. But you may also suffer tunnel-vision, rapid breathing and heart-rate. You may also suffer shaking, which is quite normal and healthy. But you will not want your attackers to see your fear and hiding these signs can be hard. Get used to getting enough air into your lungs without looking like you've lost control of your fear. The effects of adrenaline can be overwhelming if you are not used to them.
In principle you could raise your adrenaline by doing something extreme immediately before training - such as a bungee jump. For a milder effect but more convenience a violent movie might help.