Workout of the Week: Three is a Magic Number


Not only does this workout share its name with one of my favorite covers of all-time, it also happens to be one of my favorite sessions to assign athletes. In fact, if I were only allowed to use one interval—but could manipulate the intensity, recovery, and number of reps to suit my needs and desires—it’d be 3-minute repetitions. What makes them magic? Three-minute reps are short enough to keep your attention, long enough that you can’t fake your way through a set of them, and versatile enough to achieve different objectives depending on the day. Let me explain. 

What: 5-7 x 3:00 at 5K effort/pace with 1:30-3:00 walking/slow jogging for recovery between repetitions OR 10-15 x 3:00 at 1/2 marathon effort/pace with 30-60 seconds of moderately paced running between reps. [Note: These are two separate workouts—two for the price of one this week!—and I would not recommend combining them into one session.]

Why: The former is a VO2 max session—let’s call it 8/10 on the perceived effort scale—and it’s the highest intensity you can maintain for the duration of the interval. If you’re running hard enough, you’ll likely be reaching for your knees after each repetition but 2-3 minutes of walking afterward should be enough time to ensure that you’re mostly recovered before beginning the next interval. The latter is more of a broken-up tempo run—let’s call it 6/10 in terms of perceived effort—and will help improve endurance, efficiency, and pacing in manageable (but still challenging) chunks of work.

Where: Anywhere!

When: Less reps at a higher intensity with an equal amount of recovery time will give you a nice fitness boost early in a training cycle and generally help you practice getting more comfortable with being uncomfortable. The same workout, say 5 x 3:00, with a little less recovery, i.e. 1:30-2:00, can serve as more of a specific session and help you dial in race pace 10-14 days out from a goal 5K or 10K. On the flipside, more reps at a lower intensity with less recovery can help improve general endurance early on in a training cycle, help you dial in pacing if you have a tendency to be erratic, and/or serve as an effective substitute for a straight-up tempo run without affecting the intention of the workout.

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Mario Fraioli

coach to inspired athletes. writer and host of the morning shakeout.
Marin County, CA

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