The Truth About HIIT For Weight Loss
HIIT & Fat Loss
LAST UPDATED: November 2018.
Author: Nicola Joyce (aka “the fit writer”) is a fitness industry copywriter who has been writing for and about sport and fitness since 2004. Nicola is a competitive drug-free bodybuilder (with two World titles at amateur level) and has also competed in powerlifting and a couple of strongman comps. Prior to her strength training days, Nicola was an endurance athlete and has even swum the English Channel twice. She can be found on all social media at: thefitwriter.
Does high intensity interval training really help strip body fat better than regular cardio?
There’s been plenty of buzz around HIIT training in recent years. But truth is, HIIT is tough. So before we all started burning ourselves into the ground with sprint intervals, let’s find out whether it’s really worth it.
Does HIIT burn more calories than steady state?
And how about fat loss, what’s the deal there?
Is the so-called afterburn effect of HIIT really all that?
Or does any cardio work just as well?
What’s HIIT Traning?
The clue is in the name: high intensity interval training.
HIIT is intense efforts interspersed with longer periods of recovery.
Think hill sprints (with the recovery being the jog back to the bottom), bike sprints, or conditioning style cardio.
Where most people go wrong is in thinking that HIIT can be done for 20-30 minutes.
If you can do it for that long, you’re missing out on the “I” for “intense”.
The work periods of HIIT need to be so intense that you can barely keep going, and you need every second of the recovery to be able to get another interval out. 5-10 minutes of true, intense HIIT should feel like the toughest workout you’ve ever done.
If it’s not intense, it’s not HIIT.
One of the most well-known forms of HIIT training is the Tabata Protocol, made famous by researcher Izumi Tabata in the 1990s.
Tabata differs slightly from most HIIT, in that the rest periods are actually shorter than the intervals.
To do Tabata, you work hard for 20 seconds, recover for 10, and repeat. In total, you do 8 rounds, for a Tabata workout of 4 minutes.
HIIT workouts can be done on cardio equipment like a stationary bike, rowing machine, or treadmill.
You can also perform HIIT with equipment like battle ropes, a loaded sled, or kettlebells.
Or you could use a running track, hill, or clear stretch of sidewalk/pavement to simply do sprints.
The key is that you perform short intervals at a true 90%+ of max effort, then recover for slightly longer than the work period. Repeat the work interval for at least 4 rounds.
HIIT vs. Steady State
Steady state cardio was the mainstay of many a bodybuilder’s contest prep for decades.
However, recently, the long slow stuff has been overshadowed by HIIT and the many headlines devoted to this short, intense form of cardio.
Studies as recently as this 2015 meta analysis looked at HIIT vs steady state cardio and concluded that “Endurance training and HIT both elicit large improvements in the VO2max of healthy, young to middle-aged adults, with the gains in VO2max being greater following HIT when compared with endurance training”.
Yet the same systematic review admits that “when compared with endurance training, there was a possibly small beneficial effect for HIT”.
So the jury is still out on whether HIIT or steady state are more effective.
How does HIIT affect fat loss?
The main argument for HIIT centres around the afterburn effect, or EPOC (excess post exercise oxygen consumption).
This means the amount of oxygen your body needs to get back to its normal resting metabolic state. Because HIIT is so demanding, your body takes longer to get back to normal afterwards, and it will continue to burn calories in this period of raised metabolic activity.
Compare this to steady state cardio, where you will feel back to normal within a few minutes.
Is HIIT better for fat loss?
This 2015 study compared the EPOC generated by HIIT, steady state cardio, and regular weight training sessions.
The results showed similar EPOC from HIIT and resistance training sessions (around 21 hours to return to normal metabolic state).
So perhaps you don’t need cardio at all: just intense lifting and an appropriate caloric intake?
Let’s look beyond the studies and be practical for a moment. The best form of cardio for you might not be the one that researchers in white coats deem optimal.
Ultimately, the best form of cardio is the one you’ll actually do.
If you’re pushed for time, and prefer to work super hard for a short period (rather than sweating it out on a stepper whilst catching up on Netflix episodes), HIIT might fit the bill.
On the other hand, if you find you dread HIIT (and don’t recover from it well either), then it’s not the best form of cardio for you.
HIIT may not be best if you have injuries, if you’re heavy, or if you can’t perform intense efforts safely. HIIT isn’t relaxing, whereas steady state can be a form of “me-time” for some people.
Steady state may not be best if you suffer with impact injuries, or if you are really pushed for time.
The best plan in the world will only work if you stick to it. So HIIT will only work for you if you will actually do it, put the right effort in, and if you can recover from it quickly enough to do it again.
Final Word: Which cardio?
As we’ve said, the most effective form of cardio will be the one you actually do.
Studies may well show a small increase in EPOC for HIIT as compared to steady state.
But if you hate HIIT so much that you only do 50% of the sessions you had planned, but you enjoy steady state so much that you never miss a session, it’s clear which one you should do.
The bottom line is that fat loss occurs in a calorie deficit.
Whether you want to achieve that through decreased caloric intake, increased caloric expenditure, or both, just make sure you get it done.
Without that basic requirement, you won’t be losing fat at all.
Get the basics right, then decide whether or not HIIT fits your lifestyle, your routine, and your personality style!