Speed

Speed is how fast you can move. Sprint across a field, throw a punch, get off the line of scrimmage — all speed.

Speed is not just “fast legs.” It’s:

• How quickly your muscles fire (rate of force development)
• How well your nervous system organizes the movement (sprint mechanics, coordination)
• How much force you can put into the ground (strength)

That last part surprises people. Stronger athletes are usually faster athletes. That’s why lifting helps sprinters, and why the weight room isn’t just for size.

Speed is also specific. Being fast at 10 yards isn’t the same as being fast at 100 meters. Being fast in a straight line isn’t the same as being fast when changing direction. Train the speed you actually need.

Speed training is nervous system training. You’re teaching your body to fire harder and more precisely. That means:

• Quality over quantity. 3 sprints at full effort beats 12 sloppy ones.
• Full recovery between reps. Speed work is not conditioning.
• Fresh legs. Never sprint hard after a heavy leg day or long conditioning session.

The speed toolkit:

Programming rules:

• 2 speed sessions per week, max. More than that and you fry your CNS.
• Before lifting, not after. Speed work needs a fresh system.
• 40–80 total high-quality reps per session. Sprints, jumps, throws combined.
• Full rest (2–5 min) between max-effort reps. If your heart rate is still elevated, wait.

Speed is not built in a single session. It’s built over months, and it plateaus fast if you overtrain.

Speed is a neuromuscular quality. It depends on how quickly and forcefully motor units can be recruited, how well they fire (rate coding), and how efficiently the whole system coordinates.

Rate of force development (RFD) is the metric that matters. RFD is how fast you can generate force — not peak force, but the slope of force production. It’s measured in milliseconds (usually 0–200ms). Two athletes can have the same 1RM squat but very different RFDs, and the higher-RFD athlete will be faster.

Neural factors that drive speed:

• Motor unit recruitment — high-threshold (fast-twitch) units must be recruited. That requires high-intensity effort (near-maximal).
• Rate coding — the firing frequency of the motor units. Trained sprinters fire faster.
• Intermuscular coordination — the timing and sequence of muscle activation. Sprinting is a specific coordination pattern that takes months to groove.
• Stretch-shortening cycle (SSC) — the tendon and muscle store and release elastic energy. Faster athletes have stiffer tendons and better SSC efficiency.

The strength-speed continuum:

You need to train across the whole spectrum. Heavy lifting builds the force reservoir. Fast work teaches the system to express it quickly.

Programming implications:

• Speed work before strength work — CNS is freshest first.
• Plyometrics 2× per week — start low-volume, build over months.
• Sprints at 95–100% effort — nothing less trains max velocity.
• Strength work 2× per week — maintain or build the force base.
• Respect the recovery window — 48 hours between hard speed sessions minimum.

Testing speed:

• 10m sprint — acceleration
• 30m sprint — acceleration + transition
• Flying 30m — top-end speed (10m build-up, 30m timed)
• Vertical jump / broad jump — power proxy
• 5-10-5 shuttle — change of direction

Test every 4–6 weeks under identical conditions. Improvements of 0.05s in the 10m or 2cm in the vertical jump are meaningful.

At the research level, speed is a biomechanical and neurophysiological problem with specific, measurable determinants.

Sprint mechanics — the key positions:

• Front-side mechanics: knee drives high, foot strikes under the hip. Overstriding (foot landing ahead of the hip) creates braking forces and slows you down.
• Ground contact time (GCT): elite sprinters spend ~80–90ms on the ground. Longer GCT = slower.
• Vertical vs. horizontal force: the best sprinters apply force horizontally, not just downward. Force orientation matters as much as magnitude.
• Stiffness: tendon and muscle stiffness (measured via spring-mass models) determines how much elastic energy returns with each step.

Sprint phases:

Different phases need different training. Acceleration work (sled pushes, 10–20m sprints) does not train max velocity. Max-velocity work (flying 30s, 60m sprints) does not train acceleration. Do both.

Post-activation potentiation (PAP):

A heavy lift or max-effort jump before a sprint can temporarily increase force output (via phosphorylation of myosin light chains and increased motor unit recruitment). This is the science behind contrast training — heavy back squat → sprint, or trap bar deadlift → vertical jump. Effects last 4–12 minutes. Best used on meet day or for advanced athletes.

Force-velocity profiling:

With a linear position transducer or app-based bar tracker, you can plot force vs. velocity for an athlete and identify whether they’re force-deficient (need more strength work) or velocity-deficient (need more speed work). Advanced athletes use this to individualize programming.

Individual variation:

• Muscle fiber type: ~45% of variance in sprint performance is genetic. Type II fibers dominate.
• Tendon length and stiffness: long Achilles tendons return more elastic energy.
• Limb lengths: longer limbs favor top-end speed but require more coordination to accelerate.
• Age and maturation: peak speed typically develops 18–25 in males, 16–22 in females. Pre-pubescent speed is trainable but the ceiling isn’t set.

Programming takeaways for advanced athletes:

• Train all phases of the sprint, not just one.
• Use contrast/complex training to exploit PAP on key days.
• Profile force-velocity every 6–8 weeks to adjust the balance.
• Sprint at 95–100% effort at least 2× per week during the speed phase.
• Back off the sprint volume when competing — speed work on fresh legs before events, minimal during.
• Sleep, protein, and CNS recovery are the limiting factors, not programming.