Bulletproof your hamstrings

Hamstring injuries are the most common problem in sprinting. If you've been around the sport long enough, you've either dealt with one yourself or watched other sprinters go through the frustration of recurring strains that derail entire seasons.

The standard advice usually focuses on one thing: eccentric hamstring work, particularly Nordic curls. And while that's not wrong, it's incomplete.

Bulletproofing your hamstrings isn't about finding the one magical exercise or prevention protocol. It's about understanding three things that work together: your sprint mechanics, eccentric strength at long muscle lengths, and how you manage your exposure to maximal velocity running.

Get all three right, and you drastically reduce your risk. Ignore any of them, and you're vulnerable no matter how many Nordics you grind through.

Let's start with the part most athletes overlook.

Your sprint technique is probably loading your hamstrings more than it should. When you're at top speed, the hamstrings get hammered during terminal swing as they work eccentrically to decelerate the lower leg before ground contact.

That's normal and unavoidable. What's not normal is making it worse through mechanical inefficiencies that amplify the stress.

Dan Pfaff has noted that hamstring risk rises sharply when the lower leg "casts out" more than about 30 degrees in front of vertical at maximum velocity. That casting action, where the shin angles forward excessively before the foot strikes, creates a longer moment arm and loads the hamstring harder than necessary.

Over-striding compounds this problem. When your foot lands too far in front of your center of mass, you're not just braking and losing speed. You're also cranking up the eccentric demand on your hamstrings with every step.

Small changes make a difference here. Striking closer under your hip rather than reaching out in front reduces hamstring tension without sacrificing speed. Adjusting your trunk angle and maintaining slightly higher stride frequency can lower accumulated strain across a full sprint.

Research on sprint biomechanics shows that these technical adjustments matter for injury risk management. Morin and Bramah emphasize this connection between mechanics and loading, noting that coaching cues focused on foot strike position and avoiding excessive lower leg extension can reduce hamstring tension while maintaining performance.

The point is that you can't strength-train your way out of poor mechanics. If your technique is creating unnecessary stress, adding more eccentric work just prepares you to handle bad movement patterns better. Fix the movement first.

Now, about that eccentric work.

Meta-analyses show that programs including Nordic hamstring exercises roughly halve hamstring strain risk in field and running athletes when compliance is high. That's a massive reduction in injury rates from one exercise category.

The reason Nordics work so well is that they build eccentric strength at long muscle lengths, which is exactly what your hamstrings need to handle terminal swing loading during sprinting.

The injury prevention benefit only shows up when athletes actually do the work consistently. Research shows Nordic compliance is often poor because the exercise is brutal, creates significant soreness initially, and doesn't feel directly connected to running performance.

The practical approach is building up gradually. Start with 2-3 sets of 3-4 reps twice weekly during your preparation phase, managing the initial soreness. Progress over several weeks to around 30-50 total reps per week spread across two sessions, which sits in the range linked to meaningful strength gains.

Once you're in competitive phases, maintaining 15-30 weekly reps keeps the adaptation without excessive fatigue.

You don't need to only do Nordics though. Romanian deadlifts, stiff-leg deadlifts, and single-leg hamstring sliders are all valuable because they challenge the hamstrings in slightly different ways and at various muscle lengths.

The research on hamstring injury prevention consistently points to long-length eccentric loading as crucial, not just one specific exercise. Combine movements to cover different hamstring functions and keep the training sustainable.

The third piece is how you actually structure your sprint exposure.

This is where many athletes get it wrong. They either avoid high-speed running when worried about hamstrings, or they load up one session per week with excessive volume thinking they're building resilience.

Both approaches increase injury risk.

Maximum velocity sprinting itself strengthens hamstrings eccentrically when progressed gradually and used consistently. The tissue adapts to the demands you place on it. But sudden spikes in sprint volume or intensity are repeatedly linked with higher hamstring strain rates.

Previous hamstring injury is one of the strongest risk factors for future strains, which tells you something important: the hamstring needs regular exposure to high-speed demands to stay resilient. Avoiding max velocity work after an injury or during preparation phases leaves you vulnerable when you finally ramp up intensity.

The smart approach is maintaining 1-2 maximal velocity sessions per week once you've built a base, carefully progressing distance and volume. Keep your weekly high-speed efforts above 90% of max velocity in the moderate range, around 4-10 hard efforts spread across 2-3 days.

Don't cluster everything into one monster session with 7-8 reps all above 90%. That's asking for problems.

Progress either distance or intensity each week, not everything simultaneously. Avoid big week-to-week jumps in total sprint meterage. Steady exposure builds adaptation. Erratic loading creates injury.

There's also the lumbopelvic control element that gets mentioned in injury prevention literature but often feels vague in practice. The basic idea is that pelvic tilt and trunk stability affect how your hamstrings load during sprinting.

If your pelvis is tilting excessively or you lack trunk control, your hamstrings work harder to stabilize and control movement. Core work focused on maintaining neutral spine position under load, particularly exercises like dead bugs and anti-rotation variations, helps create a stable platform for your hamstrings to work from.

It's not glamorous, but it matters.

The mistake athletes make is thinking hamstring injury prevention is about finding the one thing that protects them. Do Nordics and you're safe. Focus on technique and you're covered. Sprint consistently and you'll be fine.

Reality is that all three elements work together as a system. Your technique determines the mechanical stress. Your eccentric strength determines your capacity to handle that stress. Your sprint exposure determines whether your tissue is adapted to the demands.

Ignore any piece and you're vulnerable regardless of what else you're doing right.

If you've dealt with hamstring issues before, this becomes even more critical. Prior injury means you need to be more deliberate about all three areas. Gradual re-exposure to top speed, continued eccentric work even when healthy, and attention to any persistent mechanical asymmetries or technical flaws.

The good news is that hamstring injuries aren't inevitable. Athletes who address technique, build eccentric strength progressively, and manage their sprint loading intelligently can train and compete at high levels without constantly worrying about their hamstrings giving out.

It just requires understanding that bulletproofing isn't about one exercise or one cue. It's about systematically addressing every factor that contributes to injury risk and doing it consistently enough that the adaptations stick.

That's what actually keeps you on the track instead of watching from the sidelines.