DEEP DIVE
Ground contact during the first few steps out of the blocks lasts about 0.20 seconds. By top speed, that drops below 0.10.
That's not a marginal difference. Those are two fundamentally different mechanical events.
In acceleration, the foot stays down long enough to push through a full range. The body is low, the angles are steep, and the demand is horizontal force production over a relatively generous contact window.
At max velocity, that window gets cut in half. There's nothing to push through. The system needs to be stiff and reactive, producing force through a stretch-shortening cycle that's over before you can think about it.
The joint torques change between phases too. The braking and propulsive force patterns at the hip and knee look different at top speed compared to the drive phase. Acceleration and max velocity aren't the same movement done faster. They're different movements.
So if the track work changes that much from session to session, it's worth asking whether the weight room is changing with it.
For a lot of programs, it isn't. Tuesday's lift looks like Thursday's lift looks like Saturday's lift. The track session shifts from acceleration to max velocity to speed endurance, but the gym stays on heavy squats regardless.
Stuart McMillan at ALTIS published a full-year training program for an elite female 200m sprinter leading into the 2019 World Championships. One thing that stands out is how deliberately he pairs the type of lifting with the type of sprint work on the same day.
On acceleration days, he programs Zone 3. Maximum strength. Heavy trap bar deadlifts, heavy split squats, slow eccentrics. Long time under tension, matching the long contacts and high force demands of the drive phase.
On max velocity days, he shifts to Zone 1. Speed-strength. Olympic derivatives, fast plyometrics, dynamic effort. The intent moves from how much force to how fast, matching the short, reactive contacts of top-speed running.
On enduring speed days, Zone 2. Work capacity. Moderate loads, higher volume, reflecting the repeated effort demands of longer intervals.
I've put together a quick reference guide that breaks this down by phase with example exercises and the reasoning behind each pairing.
There's research behind this approach too. A 2025 paper on preloading protocols found that heavy squats at around 90% 1RM improved 10 to 30 meter sprint performance when performed 4 to 7 minutes before sprinting. Depth jumps showed similar benefits for short sprints when the timing was right.
But when the protocol didn't match the sprint demand, there was no improvement at all. The pairing itself mattered.
Worth flagging that these potentiation effects appeared in well-trained athletes. If you're working with younger sprinters who haven't built a solid strength base, the acute performance boost may not show up in the same way. The principle still applies to how you structure training. But accessing that immediate potentiation seems to require a certain level of training maturity.
There's a broader question about transfer here too. A systematic review by Van Hooren and Bosch looked at whether resistance training enhances rapid force development in fast, unloaded movements like sprinting.
What they found was that traditional slow, heavy lifts don't always transfer well to high-velocity tasks. The exercise needs to match the coordination and time constraints of the movement you're trying to improve.
A back squat with a three-second eccentric makes sense on acceleration day. The contacts are long enough for that kind of force expression to matter.
That same squat is a poor fit for a max velocity day, where ground contact lasts less than a tenth of a second. On those days, jump squats, reactive bounding, and fast pulls better reflect what the nervous system is actually doing on the track.
Now think about what happens when the pairing goes wrong. You run flying 30s in the morning to develop top-end speed. Then you go to the gym and grind through heavy sets of 5 with slow eccentrics.
You've layered a high-damage, long-tension stimulus on top of a session that was supposed to be about speed and reactive stiffness. The signals compete. The adaptation you were chasing gets muddied by what came after.
Flip it around and things line up. Flying 30s followed by jump squats and speed pulls. The weight room reinforces the same quality the track was developing.
You don't need to overhaul your exercise selection to apply this. The same squat pattern can serve both days depending on load and intent.
Back squat at 85% with a controlled tempo on an acceleration day. Jump squat at 40% with maximum velocity intent on a max velocity day. Same pattern. Completely different force-time demand.
And this doesn't have to be rigid. McMillan was clear that individual needs come first. Some athletes won't need Zone 2 work. Others might need heavy strength year-round regardless of what's happening on the track. The framework is a starting point, not a prescription.
But the question is worth asking every week. Look at your schedule. What quality is each track session targeting? Is the lifting that day reinforcing it, or pulling somewhere else?
When the two line up, the adaptations stack. When they don't, you end up working harder for a less clear result.