40/20 intervals are designed around 40 seconds of work followed by 20 seconds of rest or active recovery. They fall under the umbrella of Tabata workouts (named after Dr. Izumi Tabata) and are often referred to as HIIT (high-intensity interval training). Over the years, many different work-to-rest ratios have been used for certain workouts, such as 20 seconds of work/10 seconds of rest, 30 seconds of work/30 seconds of rest, 40 seconds of work/20 seconds of rest, etc. All of these work on similar principles.
During the intense 40 seconds of work, you will be close to or at your lactate threshold (i.e., the point at which your muscles begin producing lactate as a byproduct 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 altogether, until lactate can be cleared.
Therefore, we want to teach your 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 clears 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.
As you can imagine, 40/20 workouts can become quite intense. So, these workouts are recommended for well-trained athletes with a solid foundation of fitness and strength. Let’s take a look at some 40/20 workouts that will train your body to become more efficient, faster and stronger.
40/20 Running Training
This workout is ideal for the track or flat terrain. Be sure you are well-fueled with carbohydrates, such as an energy bar (plus 20-30oz water), prior to starting this workout.
Let’s say your goal is to run 6:00/mile for a 5K. Begin with a 2-3 mile gradual warm-up run. Then it’s time to begin the 40/20 portion of the workout. Run 40 seconds at your goal 5k pace (6:00/mile) and then jog 20 seconds at 30/mile slower than the goal pace (6:30/mile). On your first attempt for this workout, continue the 40/20 for 1 mile and then, over time, gradually build up to 3-4 miles. Following the workout, warm down with an easy 1-mile jog.
The next phase of this workout is to press the pace a bit more so that we can continue to raise the fitness ceiling. Once you master the workout above, try the next one: Begin with a 2-3 mile gradual warm-up run. Then run 40 seconds at 10/mile faster than your 5K goal pace (5:50/mile) and then jog 20 seconds at 20-:30/mile slower than your goal pace (6:20-6:30/mile). Gradually and progressively build up to 3-4 miles of the 40/20. Following the workout, warm down with an easy 1-mile jog.
For the more advanced runner, these workouts can be done more frequently, every 7-10 days. For those runners new to this type of intensity, performing this workout once every 3-4 weeks is ideal.
40/20 Intervals for Cycling
This workout is ideal for the stationary trainer. Again, be sure you are rested and well-fueled with carbohydrates, such as an energy bar (plus 20-30oz water), prior to starting this workout.
Let’s say your goal is to hold 300 Watts for a 20k Time Trial. Begin with a 30-minute gradual warm-up. Then ride 40 seconds (90+ rpm) at your TT goal (300W), followed by 20 seconds at 200W. Continue this 40/20 pattern for 10 minutes. And over time, gradually increase the 40/20 to 30 minutes. Following the workout, pedal easy for 10 minutes to cool down.
Once you have mastered the above workout, let’s move into phase 2. Begin with a 30-minute gradual warm-up. Then ride 40 seconds (90+ rpm) at 10W more than your TT goal (310W), followed by 20 seconds at 210W. Continue this 40/20 pattern for 10 minutes. Over time, gradually increase the 40/20 to 30 minutes. Following the workout, pedal easy for 10 minutes to warm down.
NOTE: When your total workout time reaches 50+ minutes, be sure to fuel your body during the ride with 1 bottle containing 150-250 calories of fluid replacement drink. Workouts like this can be performed once every 10-14 days.
40/20 Training for Strength & Conditioning
This bodyweight strength & conditioning workout can be performed 2-4 times per week, As always, be sure you are well-fueled with carbohydrates, such as an energy bar (plus 20-30oz water), prior to starting this workout. This workout consists of four exercises:
Push-ups (keep your knees on the ground if necessary)
Sit-ups
Squats (body weight)
Jump Rope
Prior to starting this workout, be sure to foam roll and stretch for 10-15 minutes. Begin with the push-ups and perform as many reps as you can in 40 seconds (chest to the floor and full elbow extension on each rep), then rest for 20 seconds. Continue this 40/20 for 3 minutes. Next, perform as many sit-ups as you can in 40 seconds, followed by 20 seconds of rest. Continue this 40/20 for 3-minutes. Following the sit-ups, perform as many reps of body weight squats (full squat, keep heels on the ground, the knee at 90°, quads parallel with the ground) as you can perform in 40 seconds, followed by 20 seconds of rest. Continue this 40/20 for 3-minutes.
Close out your strength and conditioning workout with a jump rope. Perform as many reps as you can in 40 seconds and then rest for 20 seconds. Continue this 40/20 for 3 minutes. Over time, gradually and progressively build up to 7 minutes for each exercise (28 minutes total workout time).
Putting it All Together
Want to add even more spice to the sauce? Perform the 40/20 Strength and Conditioning workout and then immediately after, knock out the Running or Cycling 40/20 workout. Strength work prior to cardiovascular work is ideal. Yes, you will feel fatigued during your run and cycling workout—this is by design. We are stretching your comfort zone and teaching the body to perform well while fatigued (we do not want race day to be the toughest thing we do!) In addition, performing the run/cycling workout following the strength work will help to minimize muscular soreness that can be a by-product of the 40/20 strength workout.
References
Devlin, J. et. al. (2014, June). Blood lactate clearance after maximal exercise depends on active recovery intensity. Retrieved from https://pubmed.ncbi.nlm.nih.gov/24739289/
Ronnestad, B. et. al. (2020, February). Superior performance improvements in elite cyclists following short-interval vs effort-matched long-interval training. Retrieved from https://pubmed.ncbi.nlm.nih.gov/31977120/
