40/20 Interval Training

40/20 Interval Training

40/20 training


Our goal at Just Paddling is to continue to improve FTP (functional threshold pace) for paddling longer distances at higher speeds and as always, explain how.

By using a combination of different intensities and lengths of Intervals to stress/rest the body’s energy systems to allow it to adapt to higher workloads which in turn gives us the ability to exercise more efficiently.


Over the years, many different work-to-rest ratios have been used for these High Intensity Interval sessions such as 20-seconds of work/10-seconds of rest, 30-seconds of work/30seconds of rest, 40-seconds of work/20-seconds of rest, etc. All of these work on similar principals.

To REST or not to REST is the key to any well-constructed training program and if followed consistently over time, will highlight the importance of when to use the right style of REST.

These interval sessions are nothing new but over many years I have seen good trainers fail to become great trainers because they get the rest in the wrong proportion to the intensity and volume in their training programs.

During the intense 40-seconds of work, you will be close to or at your Lactate Threshold ( the point at which your muscles begin producing lactate as a by-product of anaerobic respiration).When you produce lactate at a faster rate than it can be utilized, it’s pretty much game over for your performance. Your muscles’ ability to contract becomes significantly diminished and you will be forced to slow to a crawl, or even stop all together, until lactate can be cleared.

Therefore, we want to train our body to utilize and clear lactate as quickly as possible, which is why you’ll want to take short rests after each interval. During the 20-seconds of active recovery/rest, your heart rate will drop, which helps to clear the lactate and allows you to make another effort. Over time, your body will become efficient at clearing lactate, and you will be able to hold a faster pace for a longer period of time.

40/20 High Intensity Intervals

Begin with a 2-3 minute warm up interval at TZ 1, 30% below FTP.

Now it’s time to begin the 40/20 portion of the workout. Paddle 40-seconds at TZ3 100% FTP pace and then train at TZ2 20%below FTP for 20-seconds.

At your first attempt for this workout, continue the 40/20 for 3 minutes and then over time, gradually build up to 3-6 minutes. Following each Set of the 40/20 take a 2-3 minute active rest at TZ 1 30% below FTP. You can do repeat sets of 30 to 60 minutes of these Interval sessions depending on your fitness level and the Training Phase you are currently in.

Once you have mastered this interval session you can combined two different Intensity 40/20 interval sets.

Add in a higher intensity set of 40/20 to increase the pace a bit more so that we can continue to raise the fitness ceiling.

Begin with a 2-3 minute train at TZ1 again and then train 40-seconds at TZ 4, 5-10% above FTP pace and then train 20-seconds at TZ2, 20% slower than FTP pace. These sets are more demanding and when done in combination with a set of 40/20’s at TZ3/TZ2 only add 1-4 minutes to each set. The 40/20 at TZ4/TZ2 can be also done as a single set.

Gradually and progressively build up to combining the two sets of the 40/20.

But by planning your training well in advance it’s easy to create variety to your training programs and motivation

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