Whether you’re looking to carve seconds from a track time or add some punch to your road-race prep, a bare-bones step-down repetition session is a helpful tool. While short repetitions make track runners and 5K/10K road specialists fast, longer reps (anything that takes over two minutes or so) produce resistance to fatigue in the trying latter stretches of a race, allowing you to maintain pace until it’s time to change gears for the final kick. And even if your primary distance is the marathon, you can benefit from an occasional purposeful injection of red-line running.
1600-1200-800-400 (or the Imperial equivalent) starting at 5K pace and accelerating to about mile pace, with a 400-meter recovery at 50% of 5K pace between reps. That is, reps of 4, 3, 2 and 1 lap on a standard outdoor track.
The total duration of the workout is about 25% longer than your 5K time, not including the warm-up and cool-down.
Background and Benefits
The third quarter of almost any race is usually the most challenging. This becomes increasingly acute with decreasing distance; races 5K and shorter not only have you flirting with your maximum sustainable heart rate for almost the entire way, but also allow little time for whatever pacing adjustments your body does allow you to make.
The primary objective of the 4-3-2-1 session is to harden you against both the psychological temptation and the physical need to let off the gas in the not-quite-last portion of any track race. When you’re far enough along to be hurting but not close enough undertake the final drive for the finish line, you can too often see potential personal bests and victories over your rivals dissolved by the inability to maintain pressure before you can start kicking for the tape for real.
Many runners find that the “step-down” nature of this workout makes it easier to do alone than structurally similar high-intensity sessions.
The session consists of 4K (~2.5 miles) of fast-paced running split into segments of 1600, 1200, 800 and 400 meters with a 400-meter jog in between. As with virtually all interval sessions, the rest period establishes the quality of the workout at least as much as the speed of the repetitions does. This recovery pace is not a stumble but for most an honest trot – half the speed you can sustain for 5K. That may seem like a jog after the 1600 rep, but you can expect it to assume additional urgency heading into the 400.
To get started, run the 1600 at your current or estimated 5K pace. Then, pick it up slightly for the 1200, shooting for a time about 5 or 6 seconds faster than your target 1200-meter split in the 1600-meter rep. Continue the same essential pattern for the 800-meter rep, aiming for a time 5 or 6 seconds faster than you passed the halfway point in the 1600, as well as the 400-meter rep, looking to run that one 5 to 10 seconds faster than the laps of the 1600.
A runner with a 20:00 5K best would aim to run the 1600 in 6:24 (1:36, 3:12, 4:48, 6:24), the 1200 in about 4:42, the 800 in 3:05-3:07, and the 400 in 1:26-1:30. This means per-lap paces of about 96, 95, 93 and 86 to 90. You’re given latitude to push a little more on the last lap, but if you’ve selected the right 5K pace and stuck to the instructions, you might find that last 400 surprisingly laborious, in a good way.
What to Watch For
Each of these reps involves running at a pace that, if fresh, you could hold for three or perhaps four times the distance. That means that the 800 is at two-mile race pace or better, while the 400 is ideally close to or faster than mile race pace.
If you’re not “on,” you may feel like you’re ready for the workout to be about over after the 1200. That’s okay, because the idea here is to focus on maintaining rhythm and form for the next two without cheating on the recovery.
If you’re unable to complete this session, you may have chosen an over-ambitious 5K pace or simply experienced an off day. If, on the other hand, you decide the workout is a keeper, consider slotting it into your regular rotation a couple of times in the two three months before a goal race.
Kevin Beck has written extensively for Running Times, Competitor, Triathlete, Men’s Fitness, Motiv Running, Marathon & Beyond, the New York Road Runners and elsewhere. The editor of Run Strong (2005) and the co-author of Young Runners at the Top (2017), Beck has coached high school cross country and adult athletes ranging from everyday marathoners to the occasional Olympian. The runner-up at the 2004 USATF 50K Road Championships, Beck holds personal bests of 14:58 for 5K, 51:32 for 10 miles, 1:08:29 for the half-marathon and 2:24:17 for the marathon.