

High-intensity interval training in any of its variations is a great way to train and will provide a wide range of benefits for those brave enough to really embrace this style of training. Try this 30 Day HIIT Challenge that builds up gradually so you can get fit in no time.
Before we get started, if you want to download the 30 Day HIIT Challenge, you can do that here!
Read on for 8 reasons why you should do HIIT!
Table of Contents
Most of us have a rough idea of what a HIIT workout is and what some of the benefits are too. But why should we do HIIT workouts, and how will they benefit us?
These are just some of the questions that I will be answering here and provide you with more reasons for including high-intensity workouts in your training plan.
Many acronyms cover high-intensity training and the many variations of this training modality. I have listed a few of the main variations below with a brief description.
- HIIT (High-Intensity Interval Training) consists of short bursts of high effort activity with even shorter recovery periods and is very anaerobic. It will undoubtedly challenge you, but it is a shorter workout in general than most set and rep type sessions. Workouts like Crossfit, Les Mills Grit, and Metafit are typical examples of HIIT style classes and workouts. Strength gains, a metabolic boost, calorie afterburn, increased cardiovascular fitness, and various health benefits are all achievable through HIIT.
- HIRT (High-Intensity Resistance Training) as above but with resistance equipment. Crossfit type workouts and circuit classes such as Les Mills Grit and Body Pump would generally fall into this category where weights are used for part or all of the training.
- HIIE (High-Intensity Intermittent Exercise) is almost the same as HIIT and HIRT above. In some instances, the work and rest ratios can vary throughout the workout.
- SIT (Sprint Interval Training) is associated more often with field sports conditioning and cardiovascular training for middle-distance endurance athletes.
To keep things simple, I will use HIIT to cover all the variations of high intensity and interval based training regimes in this post.
What is a HIIT workout?
So what is a HIIT workout? What does it look like? In its most simple form, it is a series of high-intensity efforts interspersed with short rest periods.
These can then be grouped into rounds. The table below outlines some typical work/rest interval times that can be applied to any number of different exercises.
The first three are based on Billat’s timings and should be completed at 85% to 95% effort, with active recovery at approximately 40% to 50% effort.
The last three session times are based on Tabata’s work, where each bout is near maximal effort while recovery is active but of minimal effort.
Work Time | Active Recovery | Effort Repetitions | No. of rounds |
2 minutes | 1 minute | 5 to 10 rounds | |
4 minutes | 2 minutes | 3 to 5 rounds | |
5 minutes | 3 minutes | 2 to 5 rounds | |
20 seconds | 10 seconds | 8 efforts | 3 to 5 rounds |
40 seconds | 20 seconds | 4 efforts | 3 to 5 rounds |
30 seconds | 30 seconds | 4 efforts | 3 to 5 rounds |
These are only some of the many variations available and should be enough for most of you to be getting on with for a while. You may also want to read Spice Up Your CV Workouts.
The first three on this list are better suited to conditioning or cardiovascular type workouts and, as such, would suit any form of gym based cv equipment, skipping, running, or even uphill power walking.
The last three suits body weight or weight resisted exercises. Whole-body, multi-joint movements are best such as squats, deadlifts, burpees, kettlebell swings, squat & press, press-ups, etc., you get the idea.
(Check out this Kettlebell Squats and Swings HIIT Workout)
You might choose to stick with one exercise for the whole workout or use several different exercises, e.g., kettlebell squat & press and kettlebell swings.
Follow the 20 seconds work, 10 seconds rest for 8 efforts swapping exercises after each 20s effort.
Taking 1 to 3 minutes recovery between rounds, you may even change exercises each round.
There are several different formats used to shape your workouts and provide target-orientated challenges.
One of my favourites is completing a set number of reps as quickly as possible. For example, I may choose 3 exercises such as burpees, kettlebell swings, and sit-ups and then complete 15, 12, 10, 8, and 5 reps of each exercise with as little rest as possible.
The repetition numbers can be anything you want; Crossfit typically uses 21, 15, and 9 repetitions.
You could use the same reps throughout, e.g., 5 x 12 reps of each exercise. It doesn’t matter as long as it challenges you. Take as little recovery as possible, but as much as you need to complete the workout.
You could also set a time limit such as 12 minutes and try to get as many repetitions or rounds of exercises completed within this time frame.
For example, 12 reps each of 3 exercises as many times through as possible in 12 minutes. This is great and can get very intense!
Try not to go too high in either repetitions or weight, as this may not be appropriate or safe. Attempting 50 repetitions of your maximum deadlift effort probably won’t end well!
These are only some of the many variations available and should be enough for most of you to be getting on with for a while.
For more workout ideas, subscribe to The HIIT Works by Get Coached at www.getcoached.net.
My best advice in putting together your program is to include strength training in some form and HIIT workouts two or three times a week each and some steady-state aerobic training approximately once every 10 to 14 days.

What are the training benefits?
There are many benefits of incorporating HIIT workouts into your training routine.
HIIT workouts will help increase your strength, muscle size, fitness levels and help reduce your body fat. In all these instances, you will need to follow an appropriate nutrition plan.
HIIT workouts are a great supplement to a hypertrophy program as it will help manage body fat levels and provide an alternative muscle stimulus to ensure ongoing growth.
If you are a competitive athlete, then HIIT workouts will undoubtedly increase your aerobic and anaerobic capacity, whether you are an endurance athlete or a field sports player.
You may just want to keep yourself fit and healthy but don’t have access to a gym. HIIT workouts are great to do at home or in the local park with limited equipment or just using your body weight. HIIT workouts are a great complement to yoga, walking, jogging, and cycling too.
(Check out How to Build a Home Gym)
A HIIT workout can be as little as 10 minutes up to 30 or 40 minutes long, depending on your fitness levels and training goals.
You could do a 10-minute session at home before or after a walk in the park, for example, or in the evening, having done a more extended cv session that morning.
There are no hard and fast rules, just a little planning and consideration regarding your training goals and your physical abilities.
What are the health benefits?
HIIT workouts help reduce the risk of metabolic diseases such as diabetes, cardiovascular and coronary artery disease, and atherosclerosis. There is also evidence that HIIT can increase arterial elasticity, which decreases with age.
HIIT/HIRT style training will not only increase your strength, aerobic, and anaerobic capacity; it will also help to reduce your body fat along with a sensible and appropriate eating plan.
(Read my Top Healthy Eating Tips)
As discussed above, there are many reasons why you should include HIIT workouts in your training routine. To summarize, here’s the list of 8 reasons why you should do the 30 Day HIIT Workout Challenge (find it here).
- Time-efficient – approximately half an hour or so training
- Strength and cardiovascular gains
- Boosts metabolism
- Increases insulin sensitivity
- Reduces age-related arterial stiffness
- Reduces the risk of metabolic diseases such as diabetes and arteriosclerosis
- Burns more calories during and after training
- Afterburn effect
The Afterburn Effect
The afterburn effect is a big part of HIIT workouts’ time-efficient nature regarding metabolic health and body fat reduction.
Imagine fitting your usual hour of training into half an hour; you might need to adjust the weights a little or your pace on the treadmill or bike, but yes, you can achieve excellent results training for less time but at a higher intensity —this is hard at first and challenging if you haven’t trained this way before.
The After Burn Effect means that your metabolism remains elevated for longer, that you continue to use calories at a higher rate for longer after a HIIT workout than you can from a standard endurance or strength session.
You work hard for short periods with shorter rest intervals or active rest in some cases. It can be a shock to the system, a thorough warm-up is essential and an excellent active cool down to flush the lactate out of your muscles too!
Completing the 30 Day HIIT Challenge will give you all of these benefits and more.
Frequently asked HIIT questions:
“Where does HIIT come from?”
- Véronique Billat used interval training of varying interval lengths to train high-level middle distance track athletes and has shown significant improvements in endurance and speed and specific physiological adaptations beyond just cardiovascular improvements.
Her studies showed that this training also worked with untrained individuals as well.
Dr. Izumi Tabata of Tabata training also looked at the training effects of short recovery interval training bouts.
This study looked at the benefits of short maximum effort intervals with brief rest intervals. This became known as Tabata rounds, 20 seconds of work with 10 seconds rest for 8 efforts equalling a 4 minute round.
Tabata and Billat’s work were geared initially towards running but is used with bodyweight and weighted exercises with significant effect.
Couple these specific regimes with traditional circuit training that’s been around for generations, and you have HIIT.
Also see: The 5 Best Dumbbell Glute Exercises
“Can I build muscle doing HIIT workouts?”
Absolutely! Have you seen the shape of some of those Crossfit athletes? These guys and girls are in excellent condition, and the majority of their workouts are HIIT/HIRT based.
(also see the 25 Benefits of Using Batteropes)
As long as your muscle is put under the appropriate training stress to overload it with a resistance of some kind, then it will adapt and grow.
HIIT will not elicit maximal hypertrophy or maximal strength. To achieve these goals, you will need to follow a specific training program with appropriate nutrition. If you are looking to maximize the benefits of any training program, good nutrition and recovery strategies are essential.
(Try this 30 Day Full Body Fitness Challenge for strength training)
Progressive Overload is a training principle that has been around and understood for a long time.
Milo of Croton, a 6th-century Greek wrestler, lifted a newborn calf onto his shoulders and repeated this every day as the calf grew until some 4 years later Milo was lifting a bull!
This is a story that is often used as an anecdote to progressive loading and can be applied to traditional strength and hypertrophy training and HIIT type workouts.
“Can I get fitter as well as stronger doing HIIT workouts?”
Definitely! HIIT will place considerable demand on your cardiovascular system as well as generate vast amounts of lactate.
This will increase your lactate tolerance and raise your lactate threshold, both of which are important for improving anaerobic and aerobic fitness.
Using resistance such as barbells, dumbells, and kettlebells as part of your HIIT workout will help increase your strength and strength endurance, boost your metabolism, and increase your calorie burn!


“What are the health benefits?”
HIIT workouts have been shown to help reduce the risk of metabolic diseases such as diabetes, cardiovascular and coronary artery disease, and atherosclerosis. There is also evidence that HIIT can increase arterial elasticity, which decreases with age.
HIIT/HIRT style training will increase your strength, aerobic, and anaerobic capacity and help reduce your body fat along with a sensible and appropriate eating plan.
“Should I only do HIIT workouts?”
Not necessarily. You can, as there is enough variety in HIIT to ensure you don’t get stale, bored, or stop adapting to the training.
You will need to ensure appropriate recovery. This type of activity is very intense by nature and requires a longer recovery time than traditional training methods.
In my opinion, and I know many coaches echo this, it is better to use HIIT/HIRT combined with other training modalities within your workout plan.
However, HIIT can also be incorporated into a strength or endurance workout plan and will add considerably to both. It is an extremely versatile way to train as the equipment you use varies, there are bodyweight options if travelling for business or pleasure, and you don’t need a tremendous amount of space for most of the workouts!
Add our 30 Day HIIT Challenge to a solid strength training routine for optimal benefits.
“How will I stay motivated if they are so tough?”
The great thing about most of the HIIT workouts is that they have some sort of target. This is typically in the form of working out for a set time, i.e., 40s work 20s rest for 10 sets, so you know you have to keep moving during the work efforts; another example would be having a set number of reps to complete as quickly as possible for the given exercises, i.e., 15, 12, 10, 8, 5 of each exercise.
Seeing your times come down or your reps and loads increase will keep you motivated as it shows you are getting fitter and stronger!
Our 30 Day HIIT Challenge will help you build gradually towards top performance.
There are lots of programs and plans available on the internet. Most of these will be generic; however, they will still be very effective and worth doing.
You could also subscribe to The HIIT Works by Get Coached at www.getcoached.net for workouts, training programs, and healthy recipes.
As you can see, there are many options, variations, and benefits to HIIT workouts, and that you don’t have to make too many changes to your current workout plan to incorporate them.
If you feel fearless or want a good challenge to kick off the New Year, why don’t you try our 30 Day HIIT Challenge (accumulator challenge)?
It is designed to build up your strength and fitness over 30 days by increasing the workload daily.
All the exercises are done at bodyweight, so no equipment is needed; it’s just you and the floor! It starts very easy but quickly progresses into a challenging workout!
30 Day HIIT Challenge PDF Download


BSc (Hons) Sport & Exercise Science
Strength & Conditioning Coach