Training heavy for strength sports and running have often been thought of as contrary objectives. Many athletes have avoided sprints like the plague because of fears they would slow or stop their gains in strength. But as more hybrid-type athletes are showing, it is possible to build a solid base of conditioning through interval running without slowing progress in weightlifting or powerlifting.
As a strength coach for Division 1 football players, I have seen athletes maintain and even gain new levels of strength while pushing to improve their level of conditioning. All that’s needed is a smart and practical structure to training. This article will provide you with a blueprint on how to safely and effectively include various types of sprints into your training so that other aspects don’t suffer. I’ll also explain how to avoid some common issues that arise for lifters.
running back
Sprints don't have to leave you weaker or injured. All that's needed is a smart plan. [Photo courtesy Pixabay]

Run to the Hills for Safety

Lifters who start out sprinting too aggressively after years of exclusively heavy lifting risk traumatic injuries or nagging pain. Your training plan should include a period of adaptation and a progression that is outlined ahead of time. Starting out with 60-meter sprints at full speed while haphazardly adding sets each week isn’t a good plan. 
Every year spent building your squat to an appreciable level of strength was time spent building horsepower. All that power means you generate greater amounts of force than the average person who decides to take up running. This is why you’re more likely to cause damage to your soft tissue structures. Strength training makes these tissues more resilient, but the forces being fed back through your joints every time your foot strikes during sprints are pretty substantial. If you’re not careful to condition slowly, you’ll wind up with aching knees, Achilles dysfunction, and pulled muscles. 
To prevent this, start with a four-to six-week training cycle that forces you to work at a submaximal pace. My favorite method for this is hill sprints. If a hill isn't available, a treadmill on an incline will be a fine substitute, although not ideal.
The incline of the hill helps to safely condition you for maximal speeds for a few reasons. First, it prevents you from over striding and reduces the deceleration component of the support phase in sprinting. In a sprint on flat ground, when your leg swings through and you actively push it behind you there is a huge braking force. This is usually the point when you pull a hamstring, if you're predisposed. The incline of the hill prevents you from being able to push through and fully extend the hip, and subsequently the foot, behind the body, reducing injury risk.
Second, knee drive is more pronounced when you’re actively trying to propel yourself upward. This practice of active knee drive builds good running mechanics for the athlete who’s not used to running and gets them comfortable running on the balls of their feet as opposed to aggressively heel striking, which is a bad habit that can potentially cause injury when sprinting on flatland. 
Do you just want to go fast?

Start Out Easy, Progress Slowly

The next way to minimize injury and ensure longevity with sprint training is to plan an easy progression and rest completely between each effort in a given workout. Sprints, if done correctly, build alactic capacity, which is the body’s ability to produce short, high-power output bouts repeatedly.
To maintain this emphasis, sprints should be no longer than 40 meters and the rest between each repetition should be at least three times longer than it took to do the sprint. If this amount of time isn’t long enough to feel recovered to repeat the third or fourth sprint at the same level, rest longer. Sprinting is about quality. Treat each sprint as a max effort attempt.
Begin your sprint training with a manageable volume of sprints that you can build on. Start with something that seems too easy. For example, do four to six 20-meter hill sprints in your first session, and then add one sprint a week for a four-week training block. Reevaluate at the end of the cycle whether it’s time to change the resistance, mode, or frequency.

Get Ready to Go Fast

One of the most common pitfalls for lifters is not adequately warming up for their sprints. Even if you just finished a leg-intensive training session, remember that strength and speed place vastly different demands on the body. Sprint movement prep should be done any time you are going to sprint. 
You’re not getting ready to run in the Olympics, so keep the prep work manageable. Here is a basic outline for running movement drills:
  • 2 x 15m high knee run
  • 2 x 15m carioca drill
  • 2 x 15m butt kicks
  • 2 x 15m backwards run
After this, a few lower-intensity runs should be done before the first maximal sprint is attempted:
  • Two to three 20m runs at 50% of top speed
  • Two 20-30m runs at 65-70% 
  • One to two 20-30m sprints at 85-90%
This should leave you ready to begin your first work set of sprint work for the day.

Arrange Training to Recover Better

Many lifters who are new to sprinting will do their sprints on days off from heavy weight training or after upper-body focused sessions. Sprints after a heavy lower-body focused training session seems counterintuitive, but this is exactly when they should be done. It’s actually the best way to prevent a large decline in strength and decrease the risk of injury.
Sprinting taxes the legs to a similar degree as a heavy lower-body weight training session. Condensing sprints and heavy weight training by doing them both in a single day or a single session helps control total fatigue. If you do your sprints on a different day from a leg-intensive session, you’ll never give yourself a chance to recover because you’ll be taxing the lower-body in the same way twice a week. It’s not sustainable. You’ll burn out too soon and possibly abandon all sprint work due to fatigue, injury, or depression that you’ve beat your head into the wall and are getting weaker.

A Simple Sprint Progression Plan

Here is an outline of an easy progression with specific blocks of training. No need to complicate things. Keep these blocks simple and linear, progressing from less to more stressful so you can slowly build work capacity, acclimate the tissues, and prepare for heavier volumes of work. Each four-week block of training can have a different focus and build on the previous one.
For example:
  • Block 1: Hill Sprints - limiting speed and overall stress but building capacity.
  • Block 2: 15-20m Starts - done on flat surface, working on acceleration.
  • Block 3: 30-60m Sprints - working on building up to top speed.
  • Block 4: Flying Sprints - working exclusively on top speed. Take 15 meters to slowly and steadily build up to top speed and then run at top speed for 10-15 meters more.

Train Smart, Train Safe

Before you include sprints in your training, consider your goals. Sprints build alactic power and capacity (the ability to repeat high power outputs), which is invaluable to the strength athlete. If your goal is to increase explosive strength but you have already built appreciable levels of strength and move weights explosively in training, sprints may not add anything in that area.
The most important thing is to train safely. You can't make progress if you hurt yourself, so follow a plan that includes an easy introductory phase and steady increases in intensity and volume after that. Progress slowly to progress consistently over the long-term.
Coaches: Teach your athletes to run with their head: