HIRT — A Safer, More Effective Alternative to HIIT
From a faster metabolism and fat loss to increased endurance, the benefits of high-intensity interval training (HIIT) are well known. Unlike steady-state cardio, this training method preserves lean mass and raises your energy expenditure during and after exercise.
But what if there was an even better way to keep fit and torch fat? We're talking about high-intensity repeat training or HIRT.
This approach isn't as strenuous as HIIT but produces similar or better results. A typical workout takes less than 30 minutes, making it ideal for those with a busy schedule.
What makes HIRT so effective is that it reduces the stress on your body and central nervous system. Compared to HIIT, it allows for more extended rest periods and hence reduces fatigue. Therefore, it requires less recovery time and doesn't drain your energy.
Eager to find out more? Let's see what HIRT is all about, how it differs from HIIT, and whether or not it's right for you!
The Scoop on HIIT Training
High-intensity interval training, or HIIT, has emerged as a time-efficient way to get lean. In clinical trials, it has been shown effective against visceral fat, a type of fatty tissue that wraps around your internal organs.
Visceral fat, or belly fat, releases chemicals that trigger inflammation and may increase your risk of diabetes, insulin resistance, heart disease, and other cardiometabolic ailments. Unlike subcutaneous fat, this type of adipose tissue is metabolic active. HIIT burns visceral fat, which in turn, may help prevent these illnesses.
Another significant advantage of high-intensity interval training is that it raises EPOC levels. The term "EPOC" stands for excess post-exercise oxygen consumption.
Simply put, HIIT is metabolically demanding and causes your body to burn calories for hours after leaving the gym to return to its normal state. The increase in oxygen consumption elevates your energy expenditure, leading to a higher resting metabolic rate.
The human body burns approximately 5 calories per litre of oxygen consumed, reports the American Council on Exercise. Due to its intense nature, HIIT increases the calorie burn during and after training. With steady-state cardio, you'll only burn calories during exercise.
Additionally, HIIT can be applied to both cardiovascular and resistance training. Generally, it's used for sprinting, plyometrics, and other exercises targeting all of the major muscles, which can further increase EPOC levels.
Due to its short duration, this training method doesn't "eat" muscle as steady-state cardio does. It may help you build and preserve lean mass due to the surge in testosterone, insulin-like growth factor-1, and growth hormone levels explain the American Council on Exercise.
Piedmont Healthcare confirms the testosterone-boosting effects of HIIT. As the researchers note, resting for one or two minutes between intervals is even more effective — and that's what HIRT is all about. But we'll discuss that later.
Prolonged endurance exercise, on the other hand, may decrease testosterone and raise the stress hormone cortisol levels, leading to muscle loss.
Think about sprinters versus marathon runners — sprinters have muscular bodies, with well-developed thighs and glutes. Marathon runners are much leaner and have less muscle overall.
What's Wrong with HIIT?
Despite its potential benefits, HIIT isn't necessarily the best way to burn fat and boost your endurance.
As the American Council on Exercise points out, this training method can place a tremendous amount of stress on your body. That's why you shouldn't do more than two or three weekly sessions — with at least 48 hours of rest in between.
A typical HIIT workout involves 30 seconds of all-out effort followed by 30 seconds of active recovery or rest. For example, you can sprint or run for 30 seconds, walk for another 30 seconds, sprint again for 30 seconds, and so on. Continue for 15 to 20 minutes or slightly longer.
Some types of HIIT, such as Tabata, involve 20 seconds of all-out effort followed by 10 seconds of rest. One round lasts four minutes. Generally, you'll complete four rounds.
This approach is time-efficient and yields better results than steady-state training, but it has its drawbacks.
First of all, it's incredibly demanding and can put your body under too much strain, especially if you're a beginner. Second, it can easily lead to overtraining and injuries. Since it's so intense, it may increase the risk of delayed onset muscle training. The short rest periods further raise this risk.
It's not uncommon for those who practice HIIT to experience dizziness, palpitations, shortness of breath, or blood pressure spikes. The rest periods are too short to allow you to recover and start a new interval. That's especially true for Tabata. Since you're moving quickly from one set or exercise to the next, you can easily get injured.
HIIT workouts are often exhausting. If you're already on the edge of overtraining, you may experience inflammation and cellular damage following a HIIT session.
The insufficient rest between intervals may result in cumulative fatigue, leaving you feeling drained. This can affect your physical performance, muscle strength, recovery time, and overall conditioning. The risks are even higher for those who are out of shape or suffering from cardiovascular problems, such as arrhythmia.
According to a 2015 review published in Diabetes Spectrum, HIIT may not be safe for those with diabetes as it may increase their risk of cardiac events. Another research paper, which was featured in the World Journal of Cardiology, indicates that HIIT may increase the risk of adverse events during or 25 hours after exercise in people with heart disease by 8%.
If you're in shape and healthy overall, HIIT is pretty much safe. However, it may still affect your physical performance, energy levels, and recovery time.
These drawbacks are mainly due to the short rest periods. Your body simply doesn't have enough time to recover between intervals, so you won't be able to put in enough effort to get results. Not to mention that you'll feel drained afterwards.
But it doesn't have to be that way. There's a safer, more effective approach to high-intensity interval training.
HIRT, or high-intensity repeat training, delivers the same benefits as HIIT but without its drawbacks. With this strategy, you'll get higher quality, less stressful workouts and recover faster. This brings us to the next point...
What Is High-Intensity Repeat Training?
High-intensity repeat training has emerged as an improved version of HIIT. This approach involves all-out efforts, typically of a shorter duration than those associated with HIIT, with longer recovery intervals. The whole point is to maintain a consistent quality of effort on every rep during high-intensity intervals.
Unlike HIIT, this training method reduces long-term stress on the body and allows you to maintain the same high-level of performance from start to finish. A typical HIRT workout alternates between 5 to 15 seconds of intense exercise and active recovery or rest periods that are about three to five times longer.
For example, you can sprint for 10 seconds, walk for 50 seconds, and repeat. Or you can jump rope at a fast pace for 15 seconds, rest for 75 seconds, jump rope for another 15 seconds, and so on. Continue for up to 30 minutes.
Craig Marker, PhD, explains that Tabata and other HIIT protocols may cause damage to the mitochondria because of the high stress placed on the body. As Marker explains, there's a fine line between mitochondrial growth and damage to the energy system. Shortening the work intervals allows for a faster recovery and reduced lactic acid buildup.
HIRT maximizes your ability to maintain and repeat the high-intensity performance. That's partly due to the short work intervals and partly due to the more extended rest periods.
Marker recommends taking about 45 seconds of rest for every 10 seconds of work. However, these numbers are not set in stone. Interval duration depends mostly on your fitness level and exercise selection, among other factors.
Is HIRT Really Effective?
This training method is safer and more effective than HIIT. Plus, it has several other advantages, such as the ability to cause a higher increase in testosterone compared to HIIT due to the longer rest intervals.
A 2016 study published in the Journal of Strength and Conditioning Research assessed the impact on rest interval length on testosterone levels in a high-intensity bench press. Subjects who took three minutes of rest between sets experienced a longer-lasting increase in total and free testosterone than those taking one minute of rest.
Another study featured in the same journal in 2012 compared the effects of repeated-sprint training versus high-intensity interval training on tennis players.
Both strategies caused improvements in aerobic fitness, but repeated sprint training was more effective at improving sprinting ability as well as both general and tennis-specific aerobic fitness. These effects occurred in as little as six weeks.
Like HIIT, HIRT can be applied to most sports and types of exercise. For example, a 2017 study in PLOS One has found that shorter rest intervals during repeated-sprint training in soccer produced different results than longer rest intervals.
As the researchers note, short rest intervals affected players' ability to maintain sprint performance constant during training.
Long-rest intervals, on the other hand, allowed them to maintain the same sprinting speed across repetitions, leading to improved sprint performance. Furthermore, soccer players who used this approach experienced a smaller increase in glycogen breakdown byproducts compared to the short-rest interval group. Their phosphocreatine stores remained higher too.
But that's not all. Current evidence also shows that taking more extended rest periods during repeated sprint training improves maximal power output to a greater extent than shorter rest intervals. These findings apply to most activities, not just sprinting, soccer, or tennis.
A recent study featured in the European Journal of Sports Sciences assessed the effect of rest intervals on treadmill running performance.
Subjects were asked to run at speeds matching their fitness level. Those who took longer periods of rest managed to maintain or exceed their target speed. These results suggest that longer recovery periods help reduce fatigue, allowing you to run faster.
Achieve Peak Performance without Suffering
Forget about the old saying No pain, no gain. You don't have to suffer to achieve peak performance, lose weight, or get stronger. HIIT has its perks, but it's taxing on your body.
Overtraining syndrome, a potential side effect of HIIT, affects the immune, endocrine, and nervous systems, causing fatigue and diminished performance. In the long run, it may lead to chronic fatigue, burnout, decreased motivation, and higher injury risk.
HIRT is much safer and works just as well as or even better than HIIT. Sure, you can still push yourself too hard and become overtrained, but the risk is smaller.
To stay safe, start with exercises that you're familiar with. Increase training duration and intensity gradually rather than killing yourself in the gym from day one.
Crank up the intensity and add new exercises to the mix as you progress. Keep your sessions short and intense. A typical HIRT workout shouldn't exceed 30 minutes.
Sprinting, for example, isn't the best choice for beginners or those who are accustomed to running. As Marker explains, most people can only maximize power in a sprint for the first few seconds. Cycling on a stationary bike, prowler training, swimming, and rowing are a better option for HIRT, allowing you to maintain your performance constant during training.
HIRT can also increase maximal strength. Marker suggests using this approach once or twice a week to get stronger overall.
If you're trying to increase your endurance, perform HIRT four or five times a week. This training method isn't as exhausting as HIIT, so it's safe to perform more than two or three weekly sessions.
Beware that HIRT alone won't help you get stronger or build mass. The same goes for HIIT. To get results, use HIRT as part of a well-rounded workout plan. Combine it with resistance training to gain size and strength, boost your metabolism, and get the most out of your gym time. That’s why I run F.I.R.E sessions.
In fact, you don't even need a gym membership for HIRT. If you work out at home, bodyweight exercises are your best bet. Push-ups, pull-ups, plank jacks, mountain climbers, pistol squats, and step-ups are all a great choice.
Consider reaching out to a personal trainer to help you design a workout that aligns with goals. Remember that nutrition is just as important as exercise, whether you want to get leaner or build mass.
So, are you ready to take your workouts to a whole new level? With HIRT, you'll get better results in less time. Get started today — a few weeks from now on, you'll be leaner, faster, and stronger overall.