
The 5K is a complex, but thrilling, race. It’s short enough to require a lot of speed, but long enough to certainly be a distance runner’s event. Ignore the speed necessary to run well and you won’t have that “higher gear” to finish strong. Skip the foundational endurance during training and you’ll crash and burn in the final mile.
So what does sound training look like for runners targeting a fast 5K? Training should include three main ingredients:
When you start planning a season, the focus should be on the ends of the speed spectrum: endurance and speed development. As you get closer to the goal race, workouts start to look more similar to the 5K itself. In other words, they get more “specific” to the demands of the race.

Many distance runners today are used to training for longer races like the half marathon or marathon where pure endurance is the priority. But the 5K presents new opportunities for different types of workouts. That begins with the long run; Instead of always running a certain number of miles at the same pace, runners training for the 5K can add more complexity to their long runs.
Long runs variations include:
The shorter the race, the less specific a “Long Slow Distance” run is to the event. So rather than focus our efforts on a workout that is unlike the race itself, we add complexity and intensity to the long run.
This principle can also be applied to tempo runs. Instead of running a solid 3–5 mile tempo run, you can add short, 30-second speed burst at roughly 5K pace every 3–5 minutes. This turns a “normal” tempo run into a lactate-clearance tempo run, where the goal is to get the body accustomed to running fast while also clearing lactate from the blood stream. This skill will come in handy in the second half of a 5K when lactate levels in the blood are rising rapidly.

Too many runners consider themselves “lungs with legs.” Their focus is on building the aerobic system with increasing mileage, long runs and tempo workouts. But this ignores the muscles that are needed to carry you across the finish line and how well those muscles communicate with your brain.
There are two main ways to build muscular strength and establish good communication pathways between them and the brain:
Strength workouts in the gym should focus on building strength, not endurance or hypertrophy (bulking up). To do this, lift 4–6 repetitions at a very challenging weight, with full recovery. Focus on basic lifts like squats, lunges, deadlifts, bench press, pull ups and rows.
Fast workouts—or drills—can take many forms:
To race fast, you have to train fast. These workouts prime the muscles and central nervous system to work powerfully and quickly, even when fatigued.

Once you’ve built high-end aerobic fitness and developed better muscular strength, it’s time for workouts to move closer to race-specific workouts. Here is a general 4-week progression of workouts that become more specific to the 5K the closer you get to your goal race:
The ultimate goal is to get your body ready to race 3.1 miles at goal 5K pace with no recovery. These workouts look increasing similar to the race itself, don’t they? Run the final workout about a week to 10 days out from your race.
Once you’ve built the supporting infrastructure (high-end aerobic fitness and muscular strength) for your 5K goal race—and then have run workouts resembling the 5K itself—you’re ready to race fast. Make sure your race pace strategy is solid, you’re tapered and well-rested, and you’ll soon be crossing the finish line in a new personal best.
Updated from an article originally published December 2018