Factors That Determine Speed

Speed plays a crucial role in the success of athletes across various sports. While the specific requirements for speed may vary between sports, it is universally regarded as a vital quality. Speed significantly impacts an athlete’s ability to reach the ball, base, or goal, outrun defenders, catch opponents, or block scoring attempts. It is often a key factor in team selection and starting positions. In this section, we will explore the factors that influence an athlete’s speed and how training can affect these factors. We will also delve into the proper technique for running at maximal speed and how to train for it. The section concludes with discussions on technique and training for acceleration and speed endurance.

Factors Influencing Speed

1. Muscle Structure: The structure of an athlete’s muscles is a significant factor in determining speed. Notably, the distribution of muscle fiber types can impact an athlete’s speed potential. Muscles contain fast-twitch and slow-twitch fibers, with fast-twitch fibers generating a large force over a short duration. Sprinters tend to have a higher percentage of fast-twitch muscle fibers, indicating their potential for greater speed.
2. Length of Muscle Fibers: Muscle fiber length is crucial for speed. Longer muscle fibers, with more sarcomeres in series, experience less force reduction at higher velocities. Additionally, longer muscle fibers can generate more force against the ground at higher speeds and contract more rapidly.
3. Shape of Muscles: The cross-sectional area (CSA) of muscles is essential for speed. Muscles with larger CSA can produce more force. However, the shape of the muscle is equally important. Studies have shown that sprinters with greater muscle thickness in specific areas of their thighs tend to be faster. The location of hypertrophied muscle tissue within a muscle may influence speed.
4. Pennation Angle of Muscle Fibers: Muscle fibers run at different angles to the tendon, known as the fiber’s pennation angle. Greater pennation angles result in more force exertion, while smaller angles allow for quicker muscle shortening. Sprinters typically exhibit a reduced pennation angle, contributing to their speed.
5. Length of the Legs: The relative length of an athlete’s legs compared to their height can affect speed. Athletes with longer legs, relative to their height, tend to run faster. Longer legs allow for greater stride length, which can enhance an athlete’s speed.
6. Ability to Use Fuel: Speed activities require the presence of adenosine triphosphate (ATP) and creatine phosphate (CP). Training may improve the activities of enzymes involved in ATP breakdown and resynthesis, enabling an athlete to exercise faster and for longer periods. Speed endurance depends on glycogen stores and the ability to resist lactic acid effects, and training can affect these factors.
7. Fatigue: Fatigue interferes with speed. Athletes should perform speed work when they are fresh to ensure proper technique and optimal speed development.
8. Mobility: Joint mobility is crucial for speed. Athletes with greater mobility experience less resistance during fast movements.
9. Stride Length and Stride Frequency: Stride length and stride frequency are key components of speed. Athletes can enhance their speed by increasing stride length or stride frequency. However, balance is essential, as excessive stride length can lead to braking during running.
10. Technique: Technique plays a pivotal role in speed development. Proper sprinting technique is essential for performance and injury prevention. Athletes should dedicate a significant portion of their training to developing sound sprinting technique through specific drills.

Maximum Velocity Running Technique

Maximum velocity running can be divided into two distinct phases: the support phase and the recovery phase. Understanding and mastering the mechanics of these phases is crucial for athletes seeking to maximize their speed.

Support Phase:

• The support phase begins when the leading foot makes contact with the ground and continues until it leaves the ground.
• The leading foot should land slightly ahead of the athlete’s center of gravity, and its placement is critical to maintaining balance and generating force.
• Hip extensors, primarily the hamstrings and glutes, perform the bulk of the work during hip extension as the foot is driven down.
• The quadriceps muscles play an essential role at touchdown, preventing excessive knee flexion and dissipating elastic energy.
• Upon ground contact, the foot should be dorsiflexed, with the big toe pulled upward to optimize elastic force production.
• The forefoot’s outside portion should make contact with the ground.
• Athletes should focus on pulling themselves over the foot and continue exerting force until their center of gravity passes over and in front of the foot.
• The support phase concludes when the toes leave the ground.

Recovery Phase:

• The recovery phase begins as the leading foot breaks contact with the ground and lasts until it makes contact again.
• As the foot leaves the ground, the ankle should be dorsiflexed, and the big toe pulled up.
• The athlete should quickly flex the knee and bring the heel up toward the hips.
• This action shortens the lever and brings the leg’s mass closer to the hip’s axis of rotation.
• Once the heel reaches the hip, the leg is swung forward with the aim of stepping over the opposite knee.
• The athlete should continue unfolding the swing leg as the ankle crosses the opposite knee.
• Hip and knee extension occur as a transfer of momentum, not an active quadriceps contraction.
• As the leg unfolds, the athlete should aim to drive it down through hip extension, returning to the support phase.
• Hamstring injuries can occur during the unfolding phase, as the hamstrings work to prevent excessive knee hyperextension.

Other Technique Considerations:

• The head should remain in natural alignment with the trunk.
• Shoulder and trunk stability is essential to avoid twisting during the sprint.
• The angle of the body varies depending on acceleration, but at maximum speed, it should be around 80 to 85 degrees.
• Muscles in the face, neck, shoulders, arms, and hands should remain relaxed to maintain limb speed and range of motion.

Arm Action:

• Arm action during maximum velocity running is crucial for balancing forces generated by the legs and initiating leg movements.
• Proper arm action is essential for achieving and improving maximum velocity.
• The elbow angle should vary from approximately 60 degrees when the arm is in front of the body to 140 degrees when it is behind.
• The emphasis should be on driving the arm backward, which, if done forcefully, will result in a natural forward arm swing due to the stretch reflex at the shoulder.
• The hand should travel from the height of the face or shoulder to the hip.
• The arms should not cross the body’s midline to avoid interference with speed.

Evaluating Speed:

• To assess maximal running velocity, tests lasting five to seven seconds are most suitable.
• Flying sprints or middle-distance sprints are the ideal evaluations for maximum speed.
• Tests should not be too long, as they mainly evaluate speed endurance, nor too short, as they primarily evaluate acceleration.
• Common tests for speed evaluation include “flying” 40 and 60-yard sprints.

Principles of Training:

• Maximum velocity training sessions should not be scheduled consecutively, typically requiring one to three days of recovery between sessions.
• Training occurs over distances of 20 to 80 yards with adequate rest between repetitions and sets to ensure full recovery.
• Athletes should run at close to 100 percent intensity to learn to run as fast as possible while maintaining good technique.
• The focus on developing stride length or frequency depends on individual capabilities and training age.

Modes of Exercise:

• Various modes of exercise are used to enhance speed, including drills, varied pace running, resisted running, and assisted running.

Drills:

• Drills are vital for developing and perfecting ideal sprinting technique. They break down the sprinting motion into components and allow athletes to work on specific elements.
• While essential for technique, drills should not replace actual sprinting, and coaches should ensure that they understand the purpose and sequence of each drill.
• Drills should be integrated into every training session with a proper sequential progression based on the athlete’s capabilities.

Varied Pace Running:

• Varied pace running, such as “ins and outs,” is an effective method to improve speed once an athlete has mastered sound technique through drills.
• It allows athletes to experience running at different speeds, practice relaxed running, and adapt to changes in speed during a run.

Resisted Running:

• Resisted running, involving the athlete pulling or carrying weight, is a useful tool to make the sprinting motion more challenging, encouraging greater muscle recruitment.
• However, it should not significantly reduce an athlete’s speed or disrupt their technique to avoid teaching undesirable habits.

Assisted Running:

• Assisted running, where the athlete is pulled or propelled to achieve greater stride frequency, can help increase muscle stiffness and elastic energy stores, contributing to speed improvement.
• Similar to resisted running, assisted running should not involve speeds exceeding 106 percent of the athlete’s maximum to prevent disruptions in technique and poor habits

Acceleration

Acceleration refers to the process of increasing speed until reaching maximum velocity. In this context, we will consider acceleration to pertain to the initial 10 to 20 yards of increasing velocity, a crucial skill for various athletic plays and events that typically do not require athletes to run at maximum velocity for extended distances.

Technique: Acceleration differs from maximum speed in two significant ways. First, during acceleration, stride length increases incrementally, resulting in initially shorter strides compared to those in full-speed running. Consequently, the shin angle during acceleration is less than that during maximum velocity running. Second, due to the reduced stride length during acceleration, the emphasis shifts to frontside mechanics, with minimal focus on backside mechanics. Key components of acceleration technique include:

• Keeping the toes up
• Employing high knee action
• Emphasizing vigorous arm movement
• Employing an active “pawing” action at footstrike
• Maintaining a tight back and stomach

Evaluating Acceleration: To assess acceleration, short-distance sprints from a standing or crouching start are ideal. The specific distance and starting position should align with the sport’s requirements. Tests covering 20 to 40 yards are excellent for evaluating acceleration. Longer sprints from a standing or crouching start can also provide insight into acceleration while integrating other aspects.

Principles of Training: Training for acceleration should adhere to similar principles as speed training, with a focus on adequate recovery and not scheduling two consecutive training sessions. Acceleration training typically involves distances of up to 80 yards, with shorter rest periods between repetitions and more extended rest intervals between sets. Some training sessions should be dedicated solely to acceleration development.

Acceleration Drills: Starting drills serve as the primary method for honing acceleration. These drills require the athlete to initiate the exercise from a stationary position. The athlete reacts to the start command and strives to increase speed while covering the designated distance. Start drills are effective because they demand acceleration, and responding to the start command enhances reaction time. Unconventional starting situations, such as starting from a push-up position, can further enhance an athlete’s quick reactions and acceleration. Longer drills covering distances of 30 yards or more can complement acceleration and also contribute to maximum velocity training. Acceleration drills should follow a progressive approach, increasing in complexity and difficulty as the athlete’s technique and fitness improve.

Speed Endurance:

Speed endurance refers to the athlete’s capacity to sustain high-speed performances for extended durations. It is especially crucial in sports or positions that demand repetitive sprinting over time.

Evaluating Speed Endurance: Speed endurance can be evaluated through various methods, including long-distance sprints covering 100 yards or more, which assess multiple qualities (acceleration, maximum velocity, and endurance). Another evaluation method involves performing numerous short-distance sprints with minimal recovery between each sprint. The 300-yard shuttle run is an example of such a test, consisting of sprinting back and forth between cones 25 yards apart.

Principles of Training: Speed endurance training usually encompasses distances ranging from 30 to 600 yards, performed at intensities between 75 to 100 percent. Rest intervals can vary significantly depending on the distance and intensity, ranging from 30 seconds to 15 minutes between repetitions, with recovery times spanning from two minutes to full recovery between sets. As with acceleration and maximum velocity training, speed endurance should not be trained in successive workouts. Designing a structured speed endurance program can be challenging due to the wide range of distance, intensity, and recovery variables. One effective approach is to analyze competition dynamics, such as work-to-rest ratios, the nature of work and recovery, and play durations, and structure training to align with these competitive requirements. Speed endurance should be adapted to accommodate the needs of various positions within a sport. For example, in a football game, with an average of 15 plays per quarter, each play lasting 4 seconds with 30 seconds of rest, a speed endurance workout could consist of sets of five 40-yard sprints with approximately 30 to 45 seconds of recovery between each sprint.