Biohacking : Combining HIIT with a Polarized Training Plan

Are you consistently getting faster, stronger and hitting your performance goals? There has been some excellent research conducted on various types of athletes which indicates that “polarized” training plans can have an enormous impact. Marathoners and swimmers who train exclusively using high volume (low effort long runs / swims) have not shown significant improvements in sprinting velocity or endurance. Training over 2 hours a day has been found to not only reduce performance, but to put the athlete at risk for overtraining syndrome leading to illness due to strain, monotony and load. The concept behind a polarized training program is to mix high intensity interval training (HIIT) for short durations and low intensity high volume workouts throughout the week with recovery days.

The above chart from a 2014 polarized training study compared four different training programs.

  1. (A) high volume low intensity (HVT)
  2. (B) lactate threshold (THR)
  3. (C) polarized (POL)
  4. (D) primarily (HIIT)

The results were clear that over the three week period group the polarized group showed massive gains while the other groups were not as significant. This is a difficult concept to except that leisurely back to back runs for up to two hours paired with high intensity on the third day can cause significant performance gains. These athletes were never training at “normal” levels rather they had very slow low effort days and super brief high intensity minutes. Here is what the gains looked like:

  • VO2Peak : +11.7%
  • Time to Exhaustion : +17.4%
  • Peak Velocity / Power : +5.1%
  • HIIT : +5.6%

Getting more specific when we talk about low intensity in this case we are talking about < 80% of peak heart rate. When we talk about high intensity days these are intense workloads > 90% peak heart rate. This leaves a gap or what is known as “the black hole” between 80% – 90% of peak heart rate. The polarization study is suggesting from its results that we should avoid drifting into the black hole. Slow training days need to stay at low effort and be longer while high intensity training needs to be extremely focused and brief. Never the two shall mix.


Competitive endurance athletes should schedule their training sessions at a ratio of 80% low intensity to 20% high intensity. Training at a moderate intensity in the black hole zone of 80% – 90% of peak heart rate has been strongly correlated with worse performance.


Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here:

Join Adafruit on Mastodon

Adafruit is on Mastodon, join in!

Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Join over 36,000+ makers on Adafruit’s Discord channels and be part of the community!

CircuitPython – The easiest way to program microcontrollers –

Maker Business — “Packaging” chips in the US

Wearables — Enclosures help fight body humidity in costumes

Electronics — Transformers: More than meets the eye!

Python for Microcontrollers — Python on Microcontrollers Newsletter: Silicon Labs introduces CircuitPython support, and more! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi

Adafruit IoT Monthly — Guardian Robot, Weather-wise Umbrella Stand, and more!

Microsoft MakeCode — MakeCode Thank You!

EYE on NPI — Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — #NewProds 7/19/23 Feat. Adafruit Matrix Portal S3 CircuitPython Powered Internet Display!

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at !

No Comments

No comments yet.

Sorry, the comment form is closed at this time.