High Intensity Interval Training (HIIT)

HIIT is the most effective training tool for fat burning and fitness around. Learn how to use it effectively.


  • HIIT has been used for years by those in the know

  • Increase fat burning and muscle adaptations

  • Twice the results in half the time

Take the HIIT!

I remember when I was training to get under 40 minutes in a 10km race. I trained a few times a week and my times were always getting faster. They started around 50 mins for a 10km run. With some new, looser shorts (yes, the heavy and restrictive ones I had were literally holding me back) and a good bit of training under my belt I got that down to 44 mins. Then I plateaued.

Running Ironman

Ironman Bolton Marathon

No matter how much I ran I couldn’t get my time down. I was going out and hitting a good 6-10km run each time but always the same time. Almost to the second. So I stopped trying for it. I figured I was just not capable of achieving a sub 40 min 10km time.

A Different Type of Training

I happened to start boxing shortly after that. Boxing was my new thing. I love to try different sports. That improvement in the beginning where you are getting better every day you train is such a nice feeling. I was boxing 5-6 times per week.

For those who don’t know, boxing involves very hard and intense work periods followed by short breathers. You throw 10 punches then relax and move around. Then again, and again. The rounds are shortish, 2 mins, although it feels like 2 hours sometimes but that’s another story.

Feeling Fighting Fit

It was after a few months of boxing that I felt really fit. I had lost muscle mass because I’d Boxing Fighting Fitstopped weight training so I was about 5kg lighter but fast and fit. Fighting fit!

Because I felt fit I decided to do a 10km run at lunchtime one day at work. To my surprise I did it in under 42 minutes! A new PB around the busy streets of central London. Was this my opportunity to break the 40 minute 10km barrier I had always wanted!?

Effective Training

Before I tell you how that plays out, let me just go over something that might help you with training if you aren’t aware of it already. If we take running as our example, there are two major areas you need to develop:

  1. The cardiovascular system
  2. The muscular system

The Cardiovascular System – This is the heart and lungs. The engine if you like. You might have great strength in your muscles but get out of breath very easily. This means your cardio system is not up to scratch. The muscle is a heart just like any other. The more you work it, the stronger it gets. If you don’t stress it at all, it will be weak and inefficient.

The Muscular System – This is to do with your muscles. You could be strong like a sprinter or have endurance like a marathon runner, or anywhere in between. Your body adapts to the training you do. It becomes FiT for Purpose. Running longer distances requires less muscle strength and more endurance.

So, when you are training for something. In this case running. You need to work both the cardiovascular and muscular systems in order for them to adapt and becoming more efficient and able to do a better job. You’ll probably find you have a weakness in one more than the other. It can be difficult to tell which, but if you get really out of breath before your legs start hurting your weakness is cardiovascular. If your legs are screwed but you’re not out of breath it’s the muscles which are weak.

Top Tip: Find out which area you are weakest in and work on that first. You have to work on all areas in the long run though.

Back to the Story…

So, after getting my fastest time I found that my cardio system was great but my legs were so sore. I was really struggling to run that distance because I was not used to it. I needed to condition my legs to run that distance and that was my weakest point at that time. So that’s what I did. I trained for a month, going out on longer runs to build up my muscular strength and endurance for running.

The Result…?

In the end I managed to get a 39:04 time in one of the winter 10k races in Regents Park. That was a great achievement for me and I was really happy with it. I learned a lot in the process and realised that in order to maximise the results sometimes you have to train differently that you would think. Which brings me nicely onto HIIT.

What is High Intensity Interval Training (HIIT)

Put simply, it is about training at high intensities for specific amounts of time. For example, you sprint at 100% effort for 60 metres. You rest for 30 seconds and you repeat that 10 times. That’s a good example of HIIT.

Why Do It?

Sprinting is a great example to use and there are a good few reasons why I believe everyone should be adding HIIT to the weekly workouts:

  1. Efficient – You don’t need to do many 100% effort sprints to feel knackered. It’ll get you working so hard you might feel sick. Try doing 10 sprints with only 30 seconds rest in between and let me know how you get on…
  2. Achievable – Everyone has their own version of 100%. It’s easy to get out there into a park and spend 15-20 mins doing this workout. If you want results this is the way to go.
  3. Explosive – When you sprint you use your whole body. It is a full body workout from your arms to your legs to your core. When you work something at 100% effort, you will see changes. The body will adapt and build stronger muscles – both cardio and muscular related ones.
  4. Equipment – there is no requirement for any equipment. You can do it anywhere there is even a small space. So it’s free and simple to follow.
  5. Muscle Building – If you do it right your muscles will be very sore when you’re not used to sprinting. That’s because you’ve pushed them to the limit and they have to build back stronger. Muscle burns fat, so it’s a good reason to do it.
  6. Cardio Improving – Working your heart and lungs to their maximum makes them adapt too. Your heart is a muscle, remember. And also the lungs and the way that oxygen is absorbed and waste products removed from the muscles will become more efficient.

HIIT workouts deliver very good results. I could go one with more reasons to use them but I think you get the picture by now.

Real Life Example…

If you’ve got this far through the article I assume it’s because you are interested. So let me give you a real life example of what I mean about HIIT being great for cardiovascular improvements. I’m currently training for the London triathlon in August 2016. It’s an Olympic distance race which means it has a 10km run in it.

I hadn’t been running for a good year, so I knew I would be out of shape running wise. Here is how I structured my initial training phases:

Weeks 1 -4: Run once per week, 5-6km. Steady pace.

Weeks 5-8: Run 1-2 times per week, 6-10km. Steady pace.

So for the first two months I just ran at a steady pace, building up the distance. Nothing too heavy, but up to the race distance of 10km. There were 3 reasons for doing this:

  1. Get myself used to running again without killing myself and becoming disheartened over not being able to run as fast as I could before
  2. Condition my legs to run that kind of distance, as well as the rest of my body
  3. Build up some cardio endurance so my heart and lungs were ready for it

The Results – I got faster over time but towards the end I had definitely plateaued. I was running more efficiently though. When I first started out my legs would ache for days after. By week 8 I could do an 8km run and be fine the next day.

Best 8km Time

  • Time: 37:42
  • Time per KM: 4:42
  • Avg Heart Rate: 158
  • Max Heart Rate: 169

How to Progress

So after this stage where my speed had plateaued and I wasn’t getting any faster each week, I stopped running longer distances and turned to a different type of training. HIIT! This is how my training looked:

Weeks 9-12: Run 1-2 times per week, doing HIIT Sprints and hill HIIT Sprints.

HIIT Sprints

  • Find a park
  • Do 5 x jumping lunges
  • Sprint 25 metres
  • Rest for 30 seconds
  • Repeat 10 times

Hill HIIT Sprints

  • Find a hill 250m long
  • I ran 2km there to warm up
  • Run the hill as fast as possible
  • Rest for 20 seconds
  • Jog back down
  • Rest until heart rate has dropped below 120 bpm
  • Repeat 4-6 times

The Results – I went for a longer run, one month after I had last been. So no longer distance stuff at all in between that time.

New Best 8km

  • Time: 35:55
  • Time per KM: 4:29
  • Avg Heart Rate: 166
  • Max Heart Rate: 177

This is a great result. I was able to increase the heart rate at which I could run, from an average of 158 to 166. My time per km dropped 13 seconds per km and I took almost 2 minutes off my time. That’s in just 4 weeks. Here are how my stats looked:

Improve 10km race time

Timings for 8km Before HIIT Training

How to improve 10km times with HIIT

Times for 8km after HIIT Training

I should point out that I was swimming and cycling in between these two times so that would definitely have helped but if I had concentrated on the running I might have even improved further.

If you want to know more about effective training methods drop me an email and I can give you a hand. Or for some home based body weight training exercises, check out my Minimal FiT Instagram page.