High-Intensity Interval Training for Endurance Athletes Builds Endurance, Speed, and Power
Among all the endurance sport training techniques out there, none have gotten the attention as high-intensity interval training or HIIT.
And with good reason.
HIIT for endurance athletes works, not only to build speed, power, and snap, but to build endurance.
Yes, you increase your aerobic capacity through really, really hard and short intervals.
So if you’re looking to build fitness as well as potentially lose weight among other health benefits, HIIT could be for you.
HIIT for Endurance Athletes is NOT Traditional Interval Work
Typically, HIIT for endurance athletes lasts no more than 60 seconds.
In fact, studies done on elite athletes show that interval sets of 30 seconds full gas with 15 seconds recovery provided significant performance gains.
Alex Hutchinson, the writer from Outside Magazine who looks at what research shows is working or not in his Sweat Science column, wrote about studies with well-trained cyclists.
“The key result is that the short-interval group improved mean power in a 20-minute cycling test by 4.7 percent after three weeks of training, while the long-interval group improved by only 1.4 percent. They also had a 3-percent increase in power output at a blood lactate concentration of 4 mmol/L, which is a standard benchmark approximating lactate threshold; the long-interval group had a 3.5-percent decrease. Several other measures also suggested that the short-interval group had gotten fitter while the other group stagnated,” Hutchinson wrote.
Hutchinson did warn that these athletes were already well-training, so they were more likely to respond to shorter efforts since they were typically already doing the longer efforts.
What Should the HIIT for Endurance Athletes Look Like?
In a now important study into the effectiveness of short versus long intervals, Ronnestad, et.al., showed that 9:30 interval session with 30 seconds on and 15 seconds off were more effective than traditional longer intervals with the same amount of work time.
The difference is that the shorter intervals allow us to work at a higher power output for the same amount of work time, therefore accumulating more time at a higher work level.
“the present study demonstrates that performing the present SI protocol, constituted by three series of 9.5 minutes with continuously 30‐second work intervals separated by 15‐second active recovery periods, induces superior training adaptations compared to performing HIT with a more classic LI protocol.”
Moreover, the short intervals also teach our aerobic systems to better buffer the waste products that build in our system from overloading.
As a coach, I often prescribe – and do them myself – 13 minutes of 30/15s as hard as I can go. The 13-minute session comes from further research done by Ronnestad.
Our studies confirmed that SI acutely led to a 14 ± 3% higher power output, 54 ± 76% longer working time above 90% of maximal oxygen uptake, and 153 ± 148% longer time above 90% peak heart rate during (30/15 short intervals) compared to (long intervals). Despite this, the elite cyclists experienced the same perceived exertion and reached similar blood lactate levels. In other words, they were able to work harder without experiencing it to be harder.Ronnestad
Monitor Perceived Exertion Rather Than Watts
The key to HIIT for endurance athletes is perceived exertion, not working at a certain power output.
Just go as hard as you can, attempting to maintain a consistent effort.
Your power output capacity on a given day changes based on training load, fatigue, daily stress, and so on.
I start with one set of 13×30/15s, then gradually over time build up to three.
I stop the intervals when I can’t maintain a similar power output for the 30 seconds.
Trust me, you’ll know when you’re done!
What is Your Interval Goal Today?
Hutchinson, in another Sweat Science column, describes the findings in a massive book on interval training.
He says there are three principles in the book, Science and Application of High-Intensity Interval Training.
The first is to know your goal for the intervals (aerobic capacity, anaerobic capacity, or neuromuscular capacity).
This depends on the timing during the season and your individual strengths and weaknesses.
You then decide the type of interval based on duration and intensity.
Finally, you decide the specifics of the interval session. How many sets, what kind of recovery, etc.
Having a coach who knows the current research is helpful in creating a polarized training program that builds performance.
So What are Your Next Steps?
Check in with your coach.
HIIT for endurance athletes is not just a matter of doing 30/15s twice a week.
To get the optimal benefit, you need to plan your endurance sport training to include intervals.
Not sure how to go about it? Have questions? Let me know.