Use this tough-but-fair run workout to strengthen both your speed and your aerobic system.

This week’s run workout is meant to be a do-it-all go-to workout when you’re not sure if you need to focus on speed or aerobic base-building. The Temp-Lek is a combination between fartlek—Swedish for “speed play”—and tempo work. The fartlek is a change of speeds that causes less fatigue and requires less recovery than a full-fledged track workout; the tempo is an increase in pace, still below race pace, that still helps the body learn how to run steadily with good form, moderately fast, while fatigued.

Since this workout is based off of effort, rather than time over distance intervals or specific heart rates, it can be performed at nearly any phase of training. In the off-season, be realistic with paces—particularly early in the set. Understand that this’ll be a good workout to knock out the rust, rather than build fitness if you haven’t been doing much fast running. In the base-building phase, this is an excellent workout for breaking through the plateau of training at one speed, without having to race. As the season wears on, break out this set to put a fine point on your fitness heading into a race, as it doesn’t require a ton of recovery or have much impact on your energy systems (if done correctly).

While the Temp-Lek can be done on a treadmill, if necessary, the fairly quick changes in pace (based off of effort) can be difficult to perform properly on a belt-driven system. Ideally do this workout outdoors—even better over rolling hills.

Warm-Up:
10 minutes easy jog
5 minutes dynamic stretching
5 minutes of (20 seconds build to Rate of Perceived Exertion (RPE) of 7/10, 40 seconds easy jog)

Main Set:
3 minutes at RPE of 5/10
30 seconds as (10 seconds at 6/10, 10 seconds at 7/10, 10 seconds at 8/10)
1:30 easy jog
3 minutes at RPE of 5/10
30 seconds as (10 seconds at 6/10, 10 seconds at 7/10, 10 seconds at 8/10)
1:30 easy jog

15 minutes at RPE of 6/10, feeling strong, but like you could go much faster if needed at the end

1:30 easy jog
3 minutes at RPE of 5/10
30 seconds as (10 seconds at 6/10, 10 seconds at 7/10, 10 seconds at 8/10)
1:30 easy jog
3 minutes at RPE of 5/10
30 seconds as (10 seconds at 6/10, 10 seconds at 7/10, 10 seconds at 8/10)

Cool-Down:
5 minutes easy jog