You may never be quick on you feet, but you can improve your quickness. When sparring, learn to use your natural talents to your advantage instead of trying to spar as others spar. If you cannot move quickly, then use power to overcome a quicker opponent. Instead of blocking to stop an attack, block to knock the opponent off balance. Blocks may be used simply as blocks, but they may also be used as attacks. If you block a quick kick with enough force to cause the opponent pain, the opponent will be hesitant to kick again.
Another way to overcome faster opponents is to be a better fighter than they are. Instead of reacting to an opponent’s movement, a good fighter “reads” an opponent and acts before the opponent makes a move. If you anticipate an attack, you have more time to move. If you want until the attack is in progress, you must move quickly. A good fighter uses his or her own position and movement to control the position and movement of the opponent. A good fighter only attacks openings, either ones that occur spontaneously or ones that the fighter creates by using fakes or feigns. A good fighter uses the correct weapon for the target being attacked.
When it comes to sparring, the process is not as important as the result. A slow, sloppy technique that scores is better than a quick, perfect technique that does not score. When performing patterns, with enough practice, you will be able to move perfectly with precision and with the required quickness. Some people may need more practice than others may, but the results may still be identical.