Long Intervals 4×4 min vs 4×8 min vs 4×16 min
What long intervals are the best to improve your Threshold Power and VO2 Max?
Today I want to research what intervals are the best for you.
What is your guess?
- 4×4 min
- 4×8 min
- 4×16 min
Testing Group and Training Protocol
35 cyclists (29 male and 6 female) with VO2 Max 52 ± 6 mL kg/min were separated into 4 groups. Training protocol was applied for 7 weeks. Intervals were prescribed at the maximal tolerate intensity.
The first group was doing only low-intensity training (8 cyclists), 4-6 sessions at low-intensity/week.
The second group (9 cyclists) was doing 2 sessions/week with 4×4 min intervals at intensity 94 ± 2 HR peak (2 min recovery between intervals) plus 2-3 low-intensity sessions/week.
The third group (9 cyclists) was doing 2 sessions/week with 4×8 min intervals at intensity 90 ± 2 HR peak (2 min recovery between intervals) plus 2-3 low-intensity sessions/week.
The fourth group (9 cyclists) was doing 2 sessions/week with 4×16 min intervals at intensity 88 ± 2 HR peak (3 min recovery between intervals) plus 2-3 low-intensity sessions/week.
Threshold improvement was highest after 4×8 min intervals, 16.2%! 9.2% after 4×16 min intervals, 8.2% after 4×4 intervals, and even 7.7% after low-intensity training.
VO2 Max Power increased by 8.5% after 4×8 min intervals, 5.2% after 4×4 min intervals, 3.0% and 2.6% after 4×16 min intervals and low-intensity training
The goal was to compare the physiological impact of intervals at the threshold and VO2 Max intensity on recreationally trained cyclists. We could see the best results for 4×8 min intervals in increasing threshold power as well as VO2 Max power. We need to take into consideration that a test group of cyclists was recreational level. That’s why we can see faster improvement in threshold and VO2 Max values.
Remember to always adjust your training plan to your needs, but it is definitely worth it, to try Polarized Training. Let me know if you need the help of a coach.
how much recovery between sets?
Good question, 3 min easy between 16 min intervals and 2 min easy between 4 min and 8 min intervals
The test is skewed/ misleading in my opinion. The groups did not accumulate the same amount of time at V02. If they would have the current literature shows almost identical adaptations. In addition no where does it show how effective they were at execution of those intervals. If you can hold the power for 16 min……..it’s NOT your V02 max power period. That is closer to 5-6 min max. Sieler has many studies with various endurance sports that show it’s time at intensity that creates adaptations. Some people may not have/want to invest the additional time at those intensities and the related percentages will help them understand what they are missing.
One last note. The 4×4 shows the greatest percentage gain of V02 per minute of work. Likely due to the ability of test subjects to actually hit and hold the intensity targets.
We always need to have in mind that this is one research, and other research on bigger groups could show little different results. Training is a very individual thing.
it is true, and testing on such a small group can be sometimes misleading, in Cyklopedia we always stress how important it is to have an optimized training plan for every individual.
What do you recommend for beginners?
I did it yesterday again but i feel the 4 series is not enough.
If 4×8 good what about 6-8×8?
Hello, it depends on your actual fitness and your goals, if that feels too easy for you, you can always increase the intensity to 100%, 105%, and 110% of FTP.