What is Speed?

What is Speed?

Speed is how fast an athlete moves the body across the ground in a straight line, and it is the single most tested physical quality in sport. The 40-yard dash at the NFL Combine, the 20-meter sprint in soccer testing, and the 100-meter dash in track all measure the same underlying capacity, just over different distances.

Coaches separate speed from two neighboring qualities: agility, which is changing direction under control, and quickness, which is reacting to a stimulus and getting the first step moving. A wide receiver can run a 4.4-second 40 and still lose a footrace to a cornerback with a faster reaction off the snap, because reaction time, acceleration, and top-end velocity are distinct skills that show up at different points of a sprint.

In the strict physics sense, speed is a scalar, a magnitude only, while velocity also carries a direction; in practice, coaches and researchers use the two words interchangeably. What actually separates a faster athlete from a slower one comes down to how much force they can drive into the ground and how quickly they can do it, not how fast their legs appear to be spinning.

Genetics set a real ceiling here: fast-twitch, or Type II, muscle fiber percentage and Achilles tendon stiffness vary between people and cannot be changed much by training. But technique, strength, and elastic-power development still move an athlete meaningfully faster inside that ceiling, which is why speed gets trained as its own quality with its own methods rather than left to show up as a side effect of other conditioning work.

How it works

Sprinting speed comes from applying force into the ground and directing enough of that force horizontally to propel the body forward, then repeating the action as many times per second as stride mechanics allow. Two phases dominate a sprint. During acceleration, roughly the first 10 to 20 meters, the athlete is well below top speed, so the capacity to keep speeding up is high.

Effective sprinters lean the body forward, drive the hip, knee, and ankle hard behind the body in what coaches call triple extension, and hold longer ground-contact times of about 150 to 300 milliseconds so more of each step's force points horizontally rather than into the sky. As velocity climbs, the body rises to a tall, upright posture and the demand shifts from horizontal to vertical force.

The job becomes applying a large force into the ground in a very short window, as little as 80 to 100 milliseconds at maximum velocity, both to support body weight against gravity and to reset the stride fast enough to hit elite stride frequencies. Stride length and stride frequency trade off against each other rather than adding freely; pushing one variable up too far without the other typically slows an athlete down.

This is why sport scientists such as Pierre Samozino and Jean-Benoit Morin describe sprinters with a force-velocity profile rather than a single number: some athletes are limited by the maximum force they can produce at low speed, others by how well they sustain force as running velocity rises. Fast-twitch muscle fiber recruitment, elastic energy return through the Achilles tendon and arch, and how quickly the nervous system can develop force all determine how much force is available in that short a ground-contact window.

The formula

Speed (m/s) = Stride length (m) x Stride frequency (strides/sec)

Neither variable should be maximized alone. Pushing stride length past what the hips and hamstrings can control shortens the quality of ground contact, and forcing stride frequency past an athlete's natural rhythm shortens each stride. Elite sprinters optimize the product of the two rather than chasing either number in isolation.

How to apply it

• Sprint technique drills: Wall drills, A-skips, and marches groove the triple-extension and shin-angle patterns that let you apply force horizontally during acceleration and vertically at top speed. Technique work is done fresh, in short doses, before any loaded or max-effort sprinting so the pattern gets reinforced, not fatigued.
• Resisted sprints (sled push or drag): Pushing or dragging a sled loaded to roughly 10 to 30 percent of body mass overloads the acceleration phase, forcing a longer forward lean and harder hip extension without breaking down sprint mechanics. Keep the load light enough that sprint speed does not drop more than about 10 percent versus an unloaded sprint.
• Plyometrics and bounding: Depth jumps, bounds, and hops train the stretch-shortening cycle, the rapid eccentric-to-concentric turnaround that lets ground-contact time at top speed stay under 100 milliseconds. This is where elastic power, not raw strength, decides how fast an athlete can reset each stride.
• Maximal strength training: Heavy squats, hip thrusts, and deadlifts trained in the 1 to 5 rep range raise the ceiling on how much force the legs and hips can produce. That raises the maximum-force end of the force-velocity curve that acceleration depends on, giving technique and resisted-sprint work more raw force to direct into the ground.
• Flying sprints and overspeed work: A 10 to 20 meter build-up into a timed 20 to 30 meter fly zone trains stride frequency and mechanics at or above race pace, without the fatigue of a standing start. This is the primary tool programs use to raise maximum velocity once acceleration mechanics are solid.
• Speed-endurance repeats: Repeated efforts of 60 to 150 meters with full recovery between reps train the ability to hold top-end velocity longer before deceleration sets in, the quality that separates a fast 40-yard time from a fast fourth-quarter sprint in a field-sport game.

Worked example

A single speed session built to develop both ends of the sprint: the acceleration out of a start and the top-end velocity through a fly zone. Full recovery between reps keeps every rep fast, since sprint quality collapses the moment fatigue creeps in.

Total true sprinting volume stays low, around 250 to 350 meters, because top-speed sprinting is a nervous-system skill, not a conditioning tool. Once technique or timed splits start slipping, the session ends there regardless of what the plan on paper called for, and the athlete walks back to full recovery between every single rep.

Speed vs agility

The two overlap constantly in field and court sports but are separate qualities on testing day. A sprinter with an elite straight-line 40 time can still be slow through a change of direction, and a shifty athlete can lack top-end speed. Team-sport programs train both, usually in the same block.

By goal

• Youth and beginner athletes: Prioritize technique and general athleticism over max-effort sprinting. Skipping, marching, and short accelerations of 10 to 20 meters build the movement pattern safely while the nervous system is still maturing. Save heavy resisted work and flying sprints for later, once mechanics are consistent.
• Team-sport athletes (soccer, football, rugby, basketball): Most game-deciding sprints in these sports run 5 to 20 meters, so weight the program toward acceleration mechanics and resisted sprints, then add a smaller dose of flying-sprint work for the occasional breakaway. Pair speed sessions with change-of-direction and reactive drills.
• Track sprinters (100m / 200m): Split the season into acceleration-dominant blocks early and maximum-velocity or speed-endurance blocks as competition approaches. Track splits with timing gates so the force-velocity profile, not just the stopwatch, tells you which quality needs the next training cycle.

Common misconceptions

• "Speed is 100 percent genetic, so you cannot really train it." Genetics set a real ceiling — fast-twitch fiber percentage and tendon stiffness differ between people — but technique work, resisted sprints, plyometrics, and strength training reliably improve sprint times inside that ceiling. Meta-analyses of resisted-sprint and plyometric programs consistently show measurable acceleration and top-speed gains over 6 to 12 weeks of training.
• "A faster leg turnover, or stride frequency, is what makes elite sprinters the fastest." Research on Usain Bolt's world-record races found his stride frequency actually averaged lower than his competitors', about 4.25 versus roughly 4.5 strides per second, while his stride length and ground-force application were superior. Turning the legs over faster only helps if each ground contact still produces enough force; frequency without force just shortens the stride.
• "The more you sprint, the faster you get." True maximum-velocity sprinting is a nervous-system skill that degrades quickly with fatigue, so quality drops the moment volume climbs too high. Elite programs cap true speed work at roughly 250 to 400 total meters per session with full recovery between reps, rather than stacking sprints back to back.
• "Speed and agility are the same thing." Speed is moving as fast as possible in one direction; agility is decelerating, stabilizing, and redirecting force to change direction. An athlete can own a great 40-yard time and still lose a cutting contest, because the two qualities are driven by different mechanics and are tested and trained separately.

Related terms

Speed FAQ

What is speed in sports performance?

Speed is the rate at which an athlete covers ground in one direction, produced by the combination of stride length and stride frequency and expressed in meters per second. It is trained in distinct phases, acceleration, maximum velocity, and speed endurance, and underlies tests like the 40-yard dash and the 100-meter sprint.

How is athletic speed measured?

Coaches measure speed with timing gates, radar guns, or GPS units over a fixed distance, most often 10, 20, 40, or 100 meters. Average speed is distance divided by time, while peak speed comes from the fastest short segment of a longer sprint, such as the 20 meters where a sprinter is running fastest.

What is the formula for speed in sprinting?

Sprint speed equals stride length multiplied by stride frequency: how far each step covers times how many steps occur per second. The two trade off against each other, so the fastest sprinters optimize the combination of the two rather than maximizing either number alone.

What is the difference between speed and agility?

Speed is moving as fast as possible in a straight line; agility is decelerating, stabilizing, and changing direction with control. A 40-yard dash tests speed, while a pro-agility shuttle or T-test tests agility. Both matter in field and court sports, but they are trained with different drills.

What is the difference between speed and quickness?

Speed is sustained straight-line velocity once an athlete is moving; quickness is how fast they react to a stimulus and get the first step going, sometimes called reactive or first-step quickness. A quick athlete can beat a faster one off the snap, the whistle, or the starting gun.

Is speed genetic, or can it be trained?

Both. Fast-twitch muscle fiber percentage and tendon stiffness are largely genetic and set an athlete's ceiling, but technique work, resisted sprints, plyometrics, and strength training reliably improve acceleration and top speed inside that ceiling, often within a single 6- to 12-week training block.

How fast can an elite sprinter run?

Elite male sprinters reach roughly 11.5 to 12.5 meters per second, about 26 to 28 mph, at top speed. Usain Bolt's peak recorded speed during his 9.58-second 100-meter world record was 12.32 m/s, hit around the 52-meter mark of the race in Berlin in 2009.

What is a good 40-yard dash time?

At the NFL Combine, skill-position athletes typically run in the 4.3 to 4.6 second range, with elite outliers near 4.2. Recreational and high-school athletes commonly run 4.8 to 5.5 seconds. The number that matters most for training purposes is improvement against your own baseline, not a fixed benchmark.

What is the best way to improve sprint speed?

Combine sprint-technique drills, resisted sprints or sled work for acceleration, plyometrics for elastic power, flying sprints for maximum velocity, and heavy strength training to raise your force ceiling. Train speed while fresh, with full recovery between reps, since fatigue degrades the exact mechanics the session is trying to build.

Why does ground contact time matter for speed?

Ground contact time is how long the foot stays on the ground each stride, roughly 150 to 300 milliseconds during acceleration and as little as 80 to 100 milliseconds at maximum velocity. Shorter, forceful contacts at top speed let an athlete reset the stride fast enough to reach elite stride frequencies.

References

1. Acceleration vs. Maximum Speed. NSCA, Kinetic Select
2. Factors Determining Agility: Speed. NSCA, Kinetic Select
3. Kinematic Stride Characteristics of Maximal Sprint Running of Elite Sprinters – Verification of the 'Swing-Pull Technique'. Journal of Human Kinetics, 2021. PMC8008308
4. Multicomponent Velocity Measurement for Linear Sprinting: Usain Bolt's 100 m World-Record Analysis. Bioengineering (Basel), 2023. PMC10669785
5. A Kinematics Analysis of Three Best 100 m Performances Ever. Journal of Human Kinetics, 2013. PMC3661886
6. The Effect of Resisted Sprint Training on Acceleration: A Systematic Review and Meta-Analysis. International Journal of Exercise Science, 2024. PMC11382779
7. Effects of Plyometric Training on Jump, Sprint, and Change of Direction Performance in Adolescent Soccer Player: A Systematic Review with Meta-Analysis. PLoS One, 2025. PMC12040276
8. The Effectiveness of Resisted Sled Training (RST) for Sprint Performance: A Systematic Review and Meta-analysis. Sports Medicine, 2018. PubMed 29926369