Unidentified marathon athletes legs running on city road

Boost Your Training with these 5 Interval Runs

Whether you’re training for the Kaiser Permanente Half Marathon & 5K or just running for fun, chances are your primary focus is on how far and how fast you can run. But to reap the full health and fitness benefits of running, you need to vary your running routine, and interval running is one of the best ways to do that.

Here are five types of interval training you can experiment with to build speed, endurance, strength and stamina.

1. Tempo Runs

A tempo run follows the three-step process of a typical run, with a warm-up period, a period of high intensity, and a cool-down. But in a tempo run, you push yourself just beyond your comfort level in the middle period. (To test, you should be able to speak a few words, but not be able to talk naturally.) Over time, gradually increase the length and pace of your high-intensity intervals with the goal of running faster at a lower level of effort.

Why Tempo Runs: Among other benefits, tempo runs build stamina by increasing your lactate threshold, which is the point at which lactic acid begins to build up in the muscles, making them tired and sore.

2. Interval Runs

Think of an interval run as shooting yourself out of a cannon – a burst of intense running at the top of your effort level, followed by a recovery period that’s longer than the speed interval. If you’re new to interval runs, use a system two minutes of hard effort, followed by three minutes of slow jogging, then repeat.

Why Interval Runs: Pushing yourself to run fast for programmed intervals builds endurance, burns fat, and helps you run more economically.

3. Fartlek Runs

This odd name, which comes from the Swedish meaning “speed play,” refers to running at varying intervals of fast, slow, and intermediate speeds. How are tempo, interval, and Fartlek runs different? According to Runners World, the key is in the concept of play – fartlek runs are casual and unstructured, alternating in effort in a playful way. After a warmup, you vary your speed, running at harder and easier effort levels for short periods of time. To keep it interesting, use simple signposts – speed fast for that maple tree! Slow down until you get to the blue house! Fartlek runs are particularly fun in a group setting, where everyone can suggest intervals, keeping it unpredictable.

Why Fartlek Runs: Varying your running intervals freely, without a plan, makes for a stress-free workout and improves mindful awareness.

4. Reverse Splits

To do these drills, also called, negative splits, start your run slowly, staying below your ability level, then pick up the pace in the middle third of your run, saving your maximum speed for the final third. A popular form of race training, reverse splits help you finish stronger and faster.

Why Reverse Splits: By building speed slowly, you preserve the glycogen stored in your muscles for as long as possible, allowing you to run longer without getting winded.

5. Hill Runs

To build strength and power while increasing aerobic capacity, there’s not better way than running up and down hills. Not only does running up and down slope build calves, thighs and glutes, but it improves your running economy so you don’t get winded as fast.

Why Hill Runs: Pushing yourself up a steep incline boosts your heart rate, amps up your respiratory function, and helps your body use oxygen more efficiently.

Veteran marathon runner Jodi Thirtyacre works for Kaiser Permanente as the manager of the Department of Allergy, Asthma and Immunology at the San Francisco Medical Center. Jodi began running when she was only nine and ran track in high school. She kept up her regimen in college and ran her first marathon at 21. Jodi is the captain of Kaiser Permanente's teams for the Half Marathon and 5K.