Increase Your Running Speed With Double-Threshold Training

A relatively new speed strategy, double-threshold training has quickly found a spot in many elite runners’ programs.

But what if you aren’t looking to make the next Olympic team or win a national sprinting title? Can the average runner benefit from this type of training? And if so, how do you implement it?

The good news is that runners of all abilities can benefit from double-threshold training as long as it is done correctly.

The even better news is that we’re about to cover what it is, why it works, and how to utilize this form of training.

Let’s dive into how double-threshold training got its start and the science behind why this relatively new training style has quickly overtaken the endurance sports world.

Defining Double-Threshold Training: What Is It?

Threshold training is a strategy that requires running at or beyond your anaerobic threshold, the point at which your body switches from primarily using your aerobic system to utilizing your anaerobic system.

A threshold training session should be comfortably hard and one you can sustain for about 60 minutes.

Your anaerobic threshold occurs when your body can no longer rely on oxygen for energy use, and it switches from using your aerobic system to anaerobic metabolism.

At this point in your training, lactic acid starts accumulating in your muscles, causing fatigue.

Threshold training teaches your body to handle higher stress levels that will ultimately increase your running performance and endurance.

For a more in-depth look at lactate threshold, how to calculate yours, and workouts to target it, read our article here.

Now, what double training does is increase the volume of training you can do in the course of one day.

The basic premise is that you perform two threshold sessions, one in the morning and one in the afternoon/evening.

Both runs must be done within the lactate threshold range.

While they should still be challenging, each run individually won’t be as hard as traditional tempo runs, since you’ll have recovery before the second session.

Typically, you’ll also mix up the “type” of threshold training you do, such as threshold intervals in the morning session and your more traditional tempo in the evening session.

Both runs must be done within certain exertion levels, and while they should still be challenging, double-threshold training won’t be as hard as traditional tempo runs, since you’ll want similar energy for your second workout of the day.

Many runners will measure lactate levels to ensure they’re effectively targeting their anaerobic system.

The History of Double-Threshold Training

Double-threshold training is often referred to as the “Norwegian Method” and was made popular by three well-known middle- and long-distance Norwegian runners, the Ingebrigtsen brothers.

But before the Ingebrigtsen brothers helped make double-threshold training more mainstream, one of the first athletes to discover double-threshold training was a Norwegian runner, Marius Bakken.

The endurance runner discovered the double-threshold training concept while examining lactate levels, speedwork, and the recovery time needed to bounce back from them.

He found that training too hard caused runners to need too much recovery time, but by finding the ideal lactate levels to train within, a runner could improve their anaerobic threshold while needing less recovery time. 

With less recovery time required, Bakken could successfully perform two threshold training sessions each day, which was the beginning of double-threshold training.

Let’s take a closer look at the science behind this training and what makes it effective.

The Science Behind Lactate & Threshold Training

To understand how double-threshold works, it’s important to have a baseline understanding of lactate levels. During a speed workout, an average runner, depending on their fitness level, may see post-run lactate levels of 6-8 mmol/l (millimoles per liter) or even higher.

Lactate levels this high require significant recovery time, making a double workout day ineffective because a runner won’t have enough energy for a second speedwork training session.

But, interestingly, this 2022 study by Bakken found that keeping lactate levels between 2.3 to 3.0 mmol/l enabled runners to improve their aerobic and anaerobic systems while providing enough recovery time for two threshold workouts on the same day. 

Bakken’s discovery allowed him to incorporate more threshold sessions into his training, giving him a significant edge compared to his competitors.

More Elites Are Using This Training Style

When a new training technique starts to illicit successful results, others quickly follow suit. And, double-threshold training is no exception.

Due to the successful results double-threshold training has, athletes across all race distances are adding it to their programs, dominating their competition, and taking down World Records. 

The following endurance athletes all include double-threshold training in their programs.

• Jakob Ingebrigtsen: Olympic Gold 1,500 Meter,  2-time World Champion, World Record Holder – 2 miles, and Indoor 1,500 & 2,000 Meters
• Gustav Iden: World Champion Ironman
• Kristian Blummenfelt: Olympic Gold Triathalon, Ironman World Champion
• Woody Kincaid: North American Indoor 5,000 Meter record

Gold medals, world records, and personal bests tend to speak for themselves, and double-threshold training is a technique that’s helped endurance athletes achieve all of the above.

Do You Need To Be an Elite To Implement Double-Threshold Training?

Not every athlete is training for gold medals and seeking to break World Records. So, is double-threshold training beneficial for the average endurance athlete?

Absolutely! Once the workouts are structured properly, double-threshold training can help improve any endurance runner’s overall time and performance.

Not every goal needs to be an Olympic medal, and no matter what yours is, double-threshold training is an effective strategy to help you hit it.

Even if you are an older runner or someone who struggles with injuries, double-threshold training can be incorporated into your program.

For older or injury-prone runners, keeping your exertion levels slightly lower, even when performing speedwork, can help lower your risk of injuries.

This means you should still run faster than the pace you run at for your long, slow runs, but hitting lactate levels between 2.3 to 3.0 mmol/l may not be realistic for you.

And, that’s okay! As long as you’re running at a pace that’s faster than your normal “slow run” pacing, and you’re incorporating two sessions a day, you’ll still see results.

How To Incorporate Double-Threshold Training Into Your Program

First, the most critical thing is making sure you get your lactate training paces right.

Most elites train with a lactate reader, which likely isn’t feasible for most of us since they are a bit expensive.

Thus, I recommend anyone implementing double threshold training to err on the side of too slow.

To support this, a 2023 study found that lactate levels can range from 2 to 4mmol/l, so runners have some wiggle room in estimating their lactate levels and thus being on the slower end means you’re still targeting your threshold without potentially overdoing it.

Second, incorporate slowly.

Try adding one double threshold session to your plan once every 3 weeks.

Yes, this is gradual, but you want to see how your body responds before implementing too heavily.

To start, keep the total volume of your threshold for the day at your normal workout volume.

So, if you normally do 5 miles (8k) of threshold then keep both sessions to no more than a total of 5 miles.

Once you get more comfortable, you can increase the total volume.

Example workout day…

Morning threshold: 1-2 mile (3k) warm-up, 5 x 1000 meters at 10 seconds slower than 10k pace with 60 seconds rest, 1-2 mile (3k cool down).

Evening session: 1-2 mile (3k) warm-up, 3 miles (5k) at 5 seconds faster than half marathon pace, 1-2 mile (3k cool down).

Training Tips For Double-Threshold Training

Looking for some tips from an Olympic runner who utilizes this training method? Check out middle- and long-distance Olympic runner Stephen Scullion’s video, which talks about strategies for how to get the most out of threshold training.

Here are a few key tips for improving your running speed using double-threshold training:

• Warm up with dynamic stretches, light strides, and 10-15 minutes of light jogging.
• Target your tempo run being between 20 to 30 minutes at a pace you can do twice in one day (allowing for ample recovery time between sessions).
• If you don’t have a lactate reader, you can monitor your heart rate instead. To do this, perform your warm-up and then run for 20 minutes at a pace that’s comfortably hard but won’t exhaust you for a second workout. Slowly jog for 10-15 minutes, and then perform it one more time. Track your heart rate for both 20-minute runs, finding the average of the two at the end of your training. You can use this number for your lactate threshold and as a way to monitor your double-threshold training pace. You may need to adjust it some, but it gives you a good starting point.
• End your threshold training with a 5-10 minute cool-down jog followed by static stretching.