DEEP DIVE
When a good athlete comes over from another sport, the temptation is to start with technique. Film them, look at the shin angle, the arms, the way the foot lands, and start fixing.
I'd wait. Not forever, but for a while, because there's something more useful to do first, and getting the order wrong is how they end up injured in their first month.
Start with what their old sport actually trained. Football and rugby are games of repeated short accelerations, ten or twenty metres at a time, most of them ending in a turn, a collision or a decision.
Holding top speed barely comes into either sport. There's rarely the space to do it and almost never a reason to.
So the athlete arrives with a lot of what you want. They can accelerate. They're conditioned, they've usually got a decent engine, and they often have real strength behind them.
What they haven't got is any meaningful time spent at the speeds a 100 is actually run at.
That matters more than it sounds, because sprinting doesn't scale gently as you get faster. Ground contact falls from around two tenths of a second in early acceleration to nine or ten hundredths at top speed.
The forces get bigger, and they arrive in half the time.
The hamstrings take the worst of it. Past about seven metres per second, what's being asked of them climbs much faster than the speed does, to the point where a thirty per cent rise in velocity can roughly double the demand.
Top speed isn't a bit harder than a hard acceleration. It's a different postcode.
Which is why the risk is front-loaded. Hamstring injuries cluster at the start of a season, when tissue meets speeds it hasn't seen in months.
For someone coming from another sport, it isn't months. They've never been there at all.
The fix isn't clever. Regular running at genuinely high speed is what prepares you for running at genuinely high speed, and no amount of Nordics reproduces what the hamstring meets at full pace.
The work on sprint exposure puts it alongside the eccentric training rather than behind it, as part of the same plan.
It's a bit like the first month of lifting when you've got soft hands. The bar tears them up, and gripping harder or tidying your technique won't stop it.
What does is handling the bar often enough, and gently enough at first, that the skin thickens. Nobody gets calluses by thinking about them.
You also don't get them by doing twenty sets on day one and losing a fortnight to blisters.
So the dose matters in both directions. Too little exposure and the tissue stays naive.
Too much and you dig a hole instead, since eccentric hamstring strength tends to fall away when athletes pile up seven or eight maximal efforts in a week.
The numbers that get used in practice sit somewhere around one to three fast sessions a week, with only a small slice of total running volume, roughly a tenth to a fifth, actually at 95% or above.
In a first block I'd start at the bottom of that and be in no rush.
Now, back to technique, because saying "leave it" deserves more of an argument than that.
The case for coaching it early is a decent one. You can see the faults plainly: overstriding, the trunk folding forwards, the pelvis tipping.
Those patterns do associate with getting hurt, and Chris Bramah's work shows they can genuinely be coached, with wickets, overhead runs and the rest.
Two things still make me want to wait.
The first is that sprinting is an automatised skill. Whoever you're coaching already has a way of running. Nobody taught it to them, they don't think about it, and it took years to settle into place.
Changing that so it holds together flat out, under pressure, in a race, takes a lot longer than it looks like it will when you start cueing. It does shift faster in a fifteen year old than in a twenty-five year old, which is an argument for getting the running in early rather than for cueing harder.
The second is that there isn't one right shape to chase. James Wild's research on team sport athletes found something he calls inter-individual degeneracy.
It's a heavy phrase for a liberating idea: athletes using clearly different technical strategies produced the same acceleration performance.
Bramah makes a similar point about pelvic tilt, noting how much of it varies among world-class sprinters, which suggests a fair bit of what we call a fault is just anatomy.
And plenty of what looks like a technical fault is a physical limit in a costume. Hip extensor strength and how stiff the leg stays on contact both shape step rate and contact time directly.
Fix those and the picture often tidies itself up without a word said about arm carriage.
So here's what I'd actually do with that first block.
The fast running goes in early and stays small. Two sessions a week, short reps, full recovery, and run at the start of a session rather than bolted onto the end of one.
That last part gets skipped more than it should. A sprint at the end of a hard session isn't really a rep at sprinting. It's a rep at running tired, which is a different skill, and the one they already own.
Across the block, let the volume of fast metres creep up rather than the intensity. The intensity is the point from day one and doesn't need building. Their tolerance for it does.
In the gym, chase what shapes the stride rather than what looks impressive on video. Hip extensor strength and stiffness through the calf and foot both feed straight into contact time, which is the thing you're actually trying to move.
Short quick-contact hops do more for that than big showy jumps, and they cost far less to recover from.
Before you coach a position, check they can physically get into it. If the hip won't extend, no cue is going to fix the stride, and you can waste a whole season blaming an athlete's focus for something anatomical.
And be honest about the timeline, because this is where people lose their nerve. Gym numbers and jump heights will move quickly, since those are the qualities they already know how to train. The times will move slowly. When the two disagree, believe the clock.
None of this means technique doesn't matter. It matters a lot, and by the second year it's most of the job.
It's just that in the first few months you're not really coaching a sprinter yet. You're building someone who can survive sprinting, often enough and fresh enough for the pattern to start changing on its own.
Get that right and you'll have an athlete who's still on the track in October, which is worth more than a tidy-looking stride in August.