Are you wondering if High-Intensity Training (HIIT) will be of benefit to you? To that question, my response is this.
If your goal is to get or stay lean and sustain your cardiovascular health, you don’t have to grind out a single lengthy session of exhausting cardio.
- Goodbye to tedious jogs.
- No droning away on one of the hamster wheels in the gym.
- Stop sacrificing hours and hours every week.
If you know what you’re doing (and you will begin by the completion of this article), you can get further out of doing a lot less cardio than you think.
If you learn what you’re doing with your diet, you don’t require to exercise more than 4 to 6 hours per week to get as lean as you’d desire.
Yes, just 3 to 5 hours of resistance training and 1 to 2 hours of cardio per week is more than adequate.
Hence, in this article, I’m going to describe five reasons why high-interval intensity training is the cardio of choice. It’s mostly a bit of a “secret weapon” for getting and staying lean.
Let’s start with a straightforward description of what high-intensity interval training is
What Is and Isn’t High-Intensity Interval Training
High-intensity interval training (HIIT) comprises short bursts of vigorous exercise interspersed with periods of low-intensity activity or rest. The idea is that you could burn the same number of calories in a shorter period.
Odds are you probably knew that, but it leaves you with some critical issues, such as…
- How “intense” do the high-intensity intervals need to be in terms of effort and time?
- How much and how long should you rest?
- What duration should the workouts be?
- How often should you perform HIIT workouts?
Basically: what passes as a HIIT workout, and how do you get the most out of this kind of training?
Well, let’s find out.
When you begin to look into research on HIIT, you’ll frequently find that exercise intensity presented in terms of percentage of VO2 max. V02 max is the maximum rate of oxygen consumption while exercising and is an essential factor in deciding one’s endurance during more lengthy bouts of exercise.
What you’ll discover in most studies that show the advantages of HIIT is that subjects achieved between 80 and 100% of their VO2 max throughout the high-intensity periods of the exercise routines.
The percentage of V02 is helpful to know but not very beneficial because the VO2 max is hard to approximate while exercising. It’s difficult to tell with any confidence whether you’re at, let’s say, 60 or 80% of VO2 max without being attached to a metabolic cart.
A more effective way of prescribing intensity in your HIIT training is thinking with your Vmax. Your Vmax is the speed where breathing becomes difficult, and you perceive that you can’t bring in as much air as your body desires. It’s about 90% of your “all-out” effort.
The initial thing to grasp is your goal throughout your high-intensity intervals is to exercise at your Vmax.
That is, you need to get moving quickly enough that your breathing becomes difficult, and you can’t completely suck in air as soon as you desire to. You need to maintain that speed for some time.
As you can guess, this requires a significant amount of effort. Think to sprint, not jog.
Repeatedly reaching and sustaining this level of effort is the whole purpose of high-intensity interval training.
If you don’t do this–if you can engage in a conversation on the phone during your “high-intensity” periods–you’re not executing HIIT.
The next thing to know is the cumulative amount of time you exercise at your Vmax defines the effectiveness of the HIIT workout.
If your workout builds up just a few minutes of Vmax exertion, it’s not going to be as productive as one that includes double that amount.
The proper amount of time of Vmax exertion is just a matter of correct workout programming. The factors at play are the duration and intensity of both your high- and low-intensity intervals and of the workouts as a whole.
We’ll discuss more how to design an effective HIIT method soon, but first, let’s chat a bit more about the advantages of this style of training.
HIIT Burns More Fat in Less Time
If a supplement or workout or claims to be a “timesaver” for increasing muscle or losing fat, it’s likely untrue.
Well, high-intensity interval training produces the goods. It’s significantly more time-efficient for losing fat than traditional “low-intensity steady-state” cardio (LISS).
For instance, a study conducted by The University of Western Ontario had subjects exercising for six weeks. The subjects were performing workouts consisting of just 4 – 6 30-second sprints in a workout burns more fat over time than workouts composed of 60 minutes of incline treadmill walking. (13).
If you add it up, that’s pretty impressive. 17 to 27 minutes of high-intensity interval training resulted in more fat loss than 60 minutes of traditional bodybuilder cardio. This study wasn’t a one-off occurrence, either–these results have been replicated in quite a few other studies as well.
Such as those conducted by East Tennessee State University, Laval University, University of New South Wales and the Baylor College of Medicine have shown that shorter, high-intensity cardio sessions result in more significant fat loss over time than more extended, low-intensity sessions. (9, 10, 11, 12)
You don’t need to do more than a couple of hours per week to enhance fat loss, with each session being only 20 to 30 minutes long.
Regardless of what exercise you perform, high-intensity intervals should involve short periods of intense training that cause an increase in heart rate (61).
The science is precise: if your goal is to burn as much fat in as little time as possible, then HIIT is the way to go.
Although the exact mechanisms behind this advantage aren’t fully understood yet, scientists have isolated several factors. Research shows that HIIT…
- boosts your metabolic rate for up to 24 hours,
- increases insulin sensitivity in the muscles, which helps your body better absorb and use the food you eat (preferably than store it as fat),
- enhances your muscles’ ability to burn fat for energy,
- raises growth hormone levels, which aids in fat loss,
- spikes catecholamine levels, which are chemicals that move fat for burning,
- and decreases post-exercise appetite, which helps deter overeating.
The benefits of HIIT for weight loss appear modest even under more carefully controlled conditions. A meta-analysis of thirty-nine studies found that people only lost about a pound of fat a month,3237, which is no better than when engaging in a continuous, moderate-intensity activity. The HIIT required about 40 percent less of a time commitment. The HIIT participants achieved in about an hour and a half a week what took the medium-intensity groups closer to two and a half hours—namely, no change in weight, but a loss of a few pounds of body fat over a few months and one inch off the waist.
- Have people run a mile at a six mph pace in ten minutes versus walk a mile at about a three mph pace in twenty minutes. What you find is that the runners burn roughly 110 calories compared to 90 calories used by the walking group. The afterburn benefit of higher-intensity activity then increases this. During the recovery days, the running group burned about an additional 50 calories compared to more like 20 calories in the walking group. Thus in total, the runners beat out the walkers by about 50 calories and did so in half the time.
HIIT Burns Calories Fast
One study compared the calories burned during 30 minutes each of HIIT, weight training, running and biking.
The researchers found that HIIT burned 25–30% more calories than the other forms of exercise (8).
There was an increase in calories burned because HIIT allows you to spend less time exercising and burn about the same amount of calories.
High-intensity interval training may help you burn more calories or burn the same amount of calories in a shorter amount of time than traditional exercise.
HIIT Provides Health Benefits
High-intensity interval training has indicated that it provides the benefits of longer-duration exercise in a much shorter amount of time. The benefits don’t stop there; it may also offer some unique health benefits (1).
A significant amount of research demonstrates that it can reduce blood pressure and heart rate and in obese and overweight people (22).
One study found that HIIT on a stationary bike for eight weeks decreased blood pressure as much as traditional continuous endurance training in adults with high blood pressure (23).
Some research is revealing that HIIT may even reduce blood pressure more than moderate-intensity exercise (24).
However, it doesn’t seem to change blood pressure in individuals with normal-weight individuals and healthy blood pressure (22).
HIIT can reduce heart rate and blood pressure, primarily in obese or overweight individuals with high blood pressure.
HIIT Reduces Blood Sugar
A summary of 50 different studies found that HIIT reduces blood sugar and improved insulin resistance more than traditional continuous exercise (26).
The effectiveness of HIIT has ar with people who have type 2 diabetes regarding improved blood sugar (27).
High-intensity interval training may be beneficial for those needing to lower blood sugar and insulin resistance. These improvements are seen in both diabetic and healthy individuals.
High-Intensity Interval Training Help With Weight Loss
The benefits of HIIT for weight loss are shown under carefully controlled conditions. A meta-analysis of thirty-nine studies discovered that people lost about a pound of fat a month, which is similar to when people perform a continuous, moderate-intensity activity.
The HIIT required about 40 percent less of a time commitment. HIIT participants achieved in about an hour and a half a week what took the medium-intensity groups closer to two and a half hours—specifically, no change in weight, but a loss of body fat over a few months and one inch off the waist.
Another study found that performing 20 minutes of HIIT three times per week lost 4.4 pounds (2 kgs) of body fat in 12 weeks without changing their diets (15). There was also a 17% reduction in visceral fat,
For obese and overweight people, HIIT is an effective method for fat loss (19, 20). One study looked at 424 obese and overweight adults and 13 experiments. The study showed that both traditional moderate-intensity exercise and HIIT could reduce waist circumference and body fat (14).
HIIT Helps To Preserve Muscle and Strength
When you’re dieting for fat loss, your primary goal after, well, losing fat, is saving muscle. And when it comes to muscle preservation, cardio has a bad reputation.
Some of this is justified. Research has revealed that the longer your cardio sessions are, the more they reduce strength and hypertrophy–but that doesn’t mean you have to fear cardio.
There are four easy steps you can take to maximize fat loss and minimize muscle loss:
1. Use an aggressive but moderate calorie deficit.
2. Eat a high-protein diet.
3. Eat a low-fat diet.
4. Eat a high carb diet.
5. Do 3 to 5 hours of resistance training per week.
6. Keep cardio to a minimum.
The reasoning behind point #6 is this: As a general rule, the fewer cardio you do, the more muscle you’ll maintain while in a calorie deficit.
You can do no cardio at all and lose fat, but this will only get you so far.
If you want to get lean (sub-10% for men and sub-20% for women), there’s a point where you have to incorporate cardio in your routine to continue losing fat. And the leaner you want to get, the more aid you’re going to need from cardio.
And so the predicament: you need to use cardio to increase your daily energy expenditure and fat loss. You also need to keep it to a minimum to best preserve muscle. How do you go about this?
Most people want to be lean more than they want to preserve muscle and don’t know of any other alternative. They choose the Dark Side: hours and hours of exhausting cardio every week to burn both fat and muscle away.
Couple this with very-low-calorie dieting, which is all too familiar, and you have a perfect storm of agony and muscle loss.
The benefit of high-intensity interval training is that it allows for a quick workout that burns more fat.
The cardio you perform has the ability to affect the gain in size and strength with weightlifting, according to research conducted at Austin State University. The subjects that walked and ran increased less strength and size compared to those that cycled. (29)
A simple method is to do 4 to 8 sets of explosive exercises on a stationary bike, treadmill, rowing machine or elliptical trainer for 30 seconds at 90 to 100 percent of maximum effort. Rest three to four minutes between sets so that you recover fully…
HIIT Helps Curb Cravings
The overeating is the biggest enemy of fat loss, and the biggest temptations to overeat are hunger and cravings.
Overeating becomes particularly problematic as you get leaner, and your “margins for error” with your calorie intake become very slim.
Well, while they claim that low-intensity cardio stimulates the appetite and leads to higher food intake is probably not true. Research shows that HIIT, in particular, can cause changes in the brain that decrease hunger and the desire to eat and increase fullness from food consumed.
Anything that improves dietary compliance is a boon to your fat loss regimen, and HIIT does just that.
How to Create the Optimal HIIT Routine
Alright, let’s now talk about creating the right HIIT workout for you.
There are five aspects to this that we need to consider:
- Type of cardio.
- Duration and intensity of the high-intensity periods.
- Intensity and duration and of the rest periods.
- The duration of the workouts.
- Frequency of the workouts.
Let’s look at each point separately.
The Best Types of HIIT Cardio
While you can use HIIT principles with any type of cardio, if your goal is to preserve muscle and strength, your best choices are biking, rowing, and sprinting.
Research shows that the type of cardio you do has a significant effect on your ability to gain strength and size through weightlifting.
What scientists found is the more a cardio exercise mimics the movement used in hypertrophy movements, like the squat, the less it diminishes strength and muscle mass.
In the study mentioned above, the subjects that bicycled in addition to the weightlifting program gained more strength and size than those that ran or walked, and they assume this was because the cycling movement emulates the squat.
Keep in mind this is a trivial point of optimization. If you can’t or don’t want to bike, row, or sprint, use whatever style of cardio you enjoy most–swimming, jump roping, Stairmaster, and so forth. It’s not going to eat your muscle away.
It’s also worth saying that you want to adjust your speed in your training more than the resistance settings offered by various machines. The goal of HIIT is to go fast and hard, not slow and hard.
How Long and Intense Your High-Intensity Intervals Should Be
As you now know, the total amount of minutes spent at Vmax is the critical factor in determining the effectiveness of your HIIT workout.
A short time at this almost-all-out level of exertion results in a “kinda-high-intensity” workout and too much may lead to fatigue and overtraining. So let’s make sure you get both of these things correct.
First, just to reemphasize, the intensity target is Vmax, which is the speed where breathing becomes difficult. You feel like you can’t bring in as much air as your body desires. It’s about 90% of your “all-out” effort.
Don’t build-up to this effort when you start a high-intensity interval. Give it everything you’ve got from the beginning. Your breathing should be laboured within 10 to 15 seconds.
In terms of duration of high-intensity intervals, 50 to 60% of Tmax is sufficient if your goal is losing fat and improving metabolic health.
In case you don’t remember, Tmax is the amount of time you can go at your Vmax speed.
Thus, for example, I find that I can bike at Vmax for about 3 minutes before having to stop (Tmax of 3 minutes). Therefore, my high-intensity intervals are 90 to 120 seconds long (yeah, it’s challenging!).
For your intervals, you can either test your Vmax (all you require is a stopwatch) or, if you’re brand-new to HIIT, begin with 1-minute high-intensity periods.
If your goal is also to enhance your conditioning, then you will need to make your workouts progressively harder.
The purpose of this is as you get fitter, your Tmax is going to increase. And as it advances, the duration of your high-intensity intervals will need to increase if you want to continue growing your cardiovascular capacity.
As you can imagine, these workouts can get pretty intense for seasoned athletes. In three HIIT studies performed with highly trained cyclists, high-intensity intervals were 5 minutes long (and enhanced their performance).
How Long and Intense Your Low-Intensity Intervals Should Be
Begin with a 1:2 ratio between high- and low-intensity intervals. For instance, 1 minute at high-intensity and 2 minutes at low.
As your fitness improves, you can work to a 1:1 ratio.
Your rest times should also be active recovery, where you continue to move, not sitting or standing still.
Studies have revealed that active, not passive; recovery is advantageous for attaining Vmax throughout the high-intensity periods. Active recovery helps to evoke the adaptive response to the exercise that we’re trying to achieve.
How Long Should Your HIIT Workouts Be?
The fantastic thing about HIIT is how much you get out of comparatively small amounts of it. That said, it can be stressful on the body, which implies you don’t want to overdo it.
Begin your workouts with 2 to 3 minutes of low-intensity warm-up and then do 20 to 25 minutes of intervals accompanied by 2 to 3 minutes of cool-down, and you’re finished.
There isn’t any need to do more than this in each workout.
How Frequently Should You Do HIIT Workouts?
How frequently you workout depends on your goals and what other types of exercise you’re doing.
I’ve noticed that 4 to 7 total hours of exercise per week is plenty for losing fat quickly and efficiently. Optimally you will combine resistance training and HIIT, which is best for both losing fat and preserving muscle.
When I’m cutting, I like to do 4 to 5 hours of weightlifting and 1.5 to 2 hours of HIIT per week. Weightlifting and HIIT allow me to get as lean as I’d like without burning out and suffering the consequences of overtraining.
The Bottom Line on High-Intensity Interval Training
Whether you want to lose fat or enhance athletic performance or both, you want to incorporate HIIT in your workout routine.
Heed the advice in this article, and you’ll receive all its benefits and avoid its only drawback. For example, the potential for overtraining due to the added stress it puts on the body.