Timing drills are short karate techniques that are executed with a partner to develop the automatic reflex action in response to an attack or a defense. Practicing these drills allows the fighter to automatically respond to an opponent's attack without actively thinking about a counter attack resulting in a much faster response time. Response to an opponent's attack should be quick and immediate without any lag time between the initiation of the attack by the opponent and the execution of your defense and counter attack.
The typical drill is a short, single technique performed by the opponent with the defending side reacting to the technique and immediately performing the defense and counter attack. Start slowly at first and gradually increase the speed. Delivery of the initiating side should not be mechanical and rhythmic but rather random and delivered at different speeds. This keeps the defending side from anticipating the move and instead makes the defending side react to the attack. This is key in making this drill work. .
As time goes on the defending side should make a conscious effort of not anticipating the attack and should try to keep the mind clear of all thoughts and focus in on the movement of the opponent. After several repetitions, conscious effort of the counter attack can be reduced or even eliminated to the point where the defense and counter is delivered reflexively.
Try working a different single technique until a reflexive movement is developed in response to the attack. For example, if we were working on the defense and counter attack to the reverse punch (gyakutsuki) , now try doing only the lead hand jab (kezame). When a reflexive response has been developed to the kezame then try having the offensive side execute either attack randomly. This now means that the defending side has to reflexively respond immediately to one of two attacks. This is not as easy as it seems, especially if the counter attack is different. Over time try adding a 3rd technique. Eventually a reflex may be developed to any number of movements. Once this is done then try doing 2 or even 3 movement techniques on the initiating side. As you can see, this is a never-ending process. Each drill develops a reflex reaction and over time, a reflex reaction can be developed to any technique that one may encounter in a tournament situation.
This drill works not only the countering side but also works on the timing for the delivery side as well so long as they focus on the timing of the delivery of the attack. The initiating side should look for mental lapses in the opponent's defense and attack at that time. For example, an ideal time to initiate an attack is shortly after a feint but not immediately. When an opponent reacts to a feint, they tense up momentarily. When they relax after tensing up, this is the ideal time to attack. Changing the time interval between the attacks also creates mental openings in the defense. Having the initiating side show a relaxing gesture such as dropping the shoulders or guard will often times cause the defending side to momentarily drop their mental guard, this is another opportune time to attack.