H.I.I.T. stands for High Intensity Interval Training and it has become more and more popular.
This is not surprising since it can produce metabolic, performance and muscular improvements usually associated with traditional cardio in much less time.
H.I.I.T. involves short bursts of work (usually 20-90s) at a high-intensity followed by a rest interval. The total workout can last anywhere between 10-30 minutes long. It’s a method of working out that saves time and can be effective at getting results if you do it right.
The question is, are you doing it right?
In 2019, a study by researchers at John Moores University compared 2 H.I.I.T. protocols over a 6-week period with 26 previously sedentary men and women performing body weight exercises.
60 H.I.I.T.: 6-10 x 60s work / 60s rest
30 H.I.I.T.: 4-8 x 30s work / 120s rest
The 60 H.I.I.T group had a 7% increase in aerobic capacity but there was no significant difference in the 30 H.I.I.T group.
Before you start changing all you H.I.I.T. workouts to 60s work with 60s rest intervals here’s why the 30 H.I.I.T group didn’t improve.
The researchers concluded that the reason the 30 H.I.I.T group didn’t improve was due to the longer rest duration which allowed the subjects heart rate to drop too much.
In other words for H.I.I.T to be effective, an elevated heart rate needs to be maintained.
One way of looking at and constructing H.I.I.T. workouts are by looking at it from a work to rest ratio perspective. For example:
60 H.I.I.T.: worked for 60s & rested for 60s ➡️ 1:1 work to rest ratio
30 H.I.I.T.: worked for 30s & rested for 120s ➡️ 1:4 work to rest ratio.
In order to make H.I.I.T. workouts effective for improving cardiovascular fitness, it’s clear you have to maintain an elevated heart rate and this can be done by manipulating your work to rest ratio.
A 1:1 ratio is effective like the 60/60 in the 60 H.I.I.T group but you could also use 30/30 or 45/45, for example.
Experiment with different durations using a 1:1 ratio and once you become fitter you can move on to a 2:1 work to rest ratio.
Pro Tip: If you really struggle with 1:1, try 1:2.
