Improving speed optimally requires you to gain strength. Both fast and heavy exercises develop the same fast-twitch muscle fibers. Heavy weights develop these fibers best as shown by the force-velocity relationship.
You need specific practice in the skills of your sport to translate this strength though. Although this may seem obvious, fast movements do differ neurally and physically compared with heavy ones. For example, speed requires more relaxation of surrounding muscles than strength, which tends to improve with more bracing. Lifting fast to augment this practice is dangerous though and has no crossover anyway.
Reasons
Thus – directly contrary to widespread popular opinion – it is obvious that very heavy movements are actually a requirement for developing speed of movement, rather than a practice to be avoided. A particular individual might be quite fast in spite of the fact that he has never practiced any sort of heavy exercise – but the same subject would have been markedly faster if he had engaged in heavy exercises.
– Arthur Jones
- Relative strength improves.
Relative strength, for the lower body in particular, improves many athletic feats. Consider what would happen if you would suddenly removed a heavy weight while attempting a tough rep during a lift. You would move fast. If your bodyweight feels lighter, you can move faster.
An athlete that can squat 450 lb. while weighing 200 lb. has more relative strength than a 300 lb. athlete that can squat 600 lb. The latter athlete has more absolute strength though.
Improving relative strength works no differently than training for absolute strength. It just requires you to watch your diet. Limit calories while training hard.
- Tendons and connective tissue within our muscles function like springs.
These allow the storing and release of elastic energy. Even everyday activities such as walking rely on them to boost efficiency. This requires less active tension, and therefore energy, from the contractile components of our muscles.
Plyometrics, also known as shock training and often associated with explosive jumping drills, aim to train the stretch-shortening cycle. This increases concentric or lifting strength in response to the loading that occurs from a stretch reflex. This process begins with an eccentric or lowering contraction through enough range of motion that quickly ends with a sudden isometric or static contraction. This then follows with a more powerful concentric or lifting contraction if the transition occurs in little time. The phases of a jump give a good example of this sequence.
Explosive strength therefore involves creating the most force in a small time frame. This depends partially upon different factors than strength.
Connective tissue lacks the capacity to grow like the contractile components of a muscle. This calls into question if you can develop more explosiveness through supranormal means. Plyometrics also force the athlete to deal with high impact and peak forces.
- Many motor units activating at once stress the nervous system.
Perfecting a movement slowly will not transfer to a fast movement of the same nature. Recruiting many motor units at once does require specific practice. This also helps to explain the concept of CNS fatigue.
Improve Speed Correctly
Limb lengths, tendon insertions, muscle fiber type ratios, baseline hormone levels, neurological factors, and other innate traits affect the expressions of strength and speed. These confuse some trainees, causing them to believe that strength and speed can oppose each other. People differ in how how much strength boosts speed, just like the different forms of hypertrophy. Strength and speed share a direct relationship though.
Many athletes mimic those that possess more potential for their activity at birth. These elite and their coaches may attribute most their progression to their routines. Practices such as Olympic lifting and periodization among other complicated and harmful ideas have thrived under this pretense.This spreads poor information, as the routines used by the best may injure and overtrain the average person.
Avoid working on your speed through lifting. This is dangerous and non-specific.
If you need more power, focus on unloaded, sports-specific skills. This will train the unique factors without unusual training that may endanger you. Plyometrics are inherent in these motions. Any fast action still carries some risk, but you stand your best chance of staying safe by approaching it as described.
Make sure your practices improve power and avoid feeling like cardio. Cardio will raise your heart rate but fail to develop power as well. This means using longer rest periods between bouts. Perform at the highest speeds when addressing this goal.
Improve speed by lifting weights safely and practicing your sport fast.