Energy Conservation

Fighting uses a lot of energy. It takes energy to get your body, or a body part, into motion, and it takes more energy to stop that motion. In a short fight, you may go full-bore to get the win. However, if you win and must fight other opponents, you may find you have exhausted your energy reserves and may not be able to fight effectively any more. To maintain your energy level over several fights or rounds, you must practice energy conservation.

Energy is conserved by doing as little work as possible. In physics, work is defined as the force times the distance: Work = force X distance. This means that if you use a lot of movement in an attack, then for a given force, you will increase your work, and therefore expend a lot of energy. Work may also be thought of as power times time: Work = power X time. For a given amount of work, the shorter the time, the greater the power. So, if you can perform a lot of work in a short time, you generate a lot of power.

Inertia is important to conservation of energy. Every time you move or stop movement, you have to overcome inertia so you must expend energy. Every time you move or stop the movement or an opponent, you have to overcome the opponent's inertia so you must expend energy.

To conserve energy

• Use as little movement as possible and force your opponent to move. For example, when you dominate the center of the ring, you force your opponent to move around you.
• Strike an opponent while he or she is moving toward you, rather than when he or she is moving away from you. Counterattacking is more energy efficient than attacking or just blocking.
• Let one movement flow into the next. Since stopping uses energy, it is more efficient to keep moving. For example, if your inside crescent kick misses, step the foot down, and keep spinning into a spin hook kick.
• Use your opponent's momentum. For example, if your opponent attempts a sweep and knocks your foot sideways, go with the motion into a spinning attack. If your opponent pushes you, instead of resisting, go with the motion of the push so the opponent becomes off balanced.
• Make sure all your attacks make contact with the opponent in some way so the opponent must expend energy in stopping your motion.
• Use your opponent’s attacking energy by redirecting it into you own attack. For example, punch inside an incoming punching arm so you block it and let its energy add to your punch by knocking it toward its target.
• Allow strikes to ricochet off one target into another target. For example, bounce a low block off a kick and change the block into a back fist attack to the head.
• Do not lean into attacks, it robs the strike of power by making it difficult to snap the strike back after impact. The extra movement of the lean requires more energy, and, if the attack misses, it will require more energy to stop the extra movement and recover to your fighting position.
  

To conserve energy while kicking

• Taekwondo is a kicking art, but kicking uses more energy than striking because the legs are heavier than the arms. So, to conserve energy while kicking, you must use proper technique and body mechanics.
• Instead of kicking where the opponent is and then trying to move the kick to track the opponent as he or she evades the attack, kick where you predict the opponent will move to when he or she detects the kick and tries to avoid it.
• Let opponents come to your kick, rather than trying to get your kick to the opponent. A spin side kick into a charging opponent is more efficient than a spin side kick that must reach out to an opponent.
• Less power is required in a kick if the opponent is moving into the kick, so use counter kicks.
• A lead side kick uses less energy when your opponent is slightly toward that side since the opponent will be more in line with your hips.
• Spin kicks require less energy when the opponent is moving toward the kick since less spin is required than trying to track an opponent moving away from the kick.
• Front and round kicks are efficient kicks when opponent is in front.
• To conserve energy, drop a missed crescent kick or axe kick onto your opponent’s guard to bring the arms down and upper body forward, and then follow-up with strikes.
• Chamber kicks high and tight before kicking and keep kicks lined up with your centerline. For example, for a side kick, lifting the knee upward into a tight chamber and kicking straight in requires less energy than trying to kick from the floor since there is less inertia in the leg the closer the weight is to the balance point, the support foot.
• Keep arms and legs in tight during spinning techniques. As the limbs extend, the spin slows, power is reduced, and more energy is needed since you must overcome more rotational inertia.
• When kicking, gravity is not your friend. High kicks require more energy than middle kicks. Low kicks to the legs require even less energy.
  

To conserve energy while throwing or grappling

• Taekwondo traditionally does not use many throwing or grappling techniques. However, in a self-defense situation, if you grab the opponent or the opponent grabs you, you should consider a throw or grapple rather than concentrating on releasing the grip.
• A properly executed throw will be smooth and effortless if the opponent is off balance. Lifting an opponent burns a lot of energy, so it is more efficient to get the opponent off balanced and then act a pivot point and have the opponent fall over you.
• Foot sweeps are more efficient throws since you are not carrying the opponent's weight.
• Less energy is expended when you guide your opponent into throwing position rather than you having to move yourself into position.
• When throwing, keep motion continuous. It requires tremendous energy to stop and then start an opponent's mass during a throw.
• Conserve energy in a joint lock by keeping your opponent close to your center of mass.
• Conserve energy by keeping your weight on the opponent as much as possible. Lying on an opponent requires little energy from you, but requires tremendous energy from the opponent to remove you. While lying on the opponent, use your body to apply pressure to sensitive areas of the opponent's body, such as by pressing the point of the elbow into a pressure point or pressing the forearm across the throat.
• If under the weight of an opponent, rather than wasting energy trying to remove the opponent, use locks or chokes that require less energy. As opponent tries to avoid them, it may also create an opportunity to escape. 
  

Sources

Sprage, M. (2002). Fighting Science: The Laws of Physics for Martial Arts. Connecticut: Turtle Press.