Most popular HIIT classes aren't actually high intensity, according to a personal trainer -- here's what a HIIT workout really is

Be:FIT LondonAlice Liveing.
  • There’s plenty of research to support the idea that high-intensity interval training, or HIIT, is just as beneficial as – if not more than – a longer, more traditional workout.
  • However, Alice Liveing, a personal trainer and Instagram star, said most HIIT workouts are actually moderately intense.
  • Real HIIT involves working to 90% capacity and can’t be maintained for a long period, she said.

There’s a growing body of research supporting the idea that high-intensity interval training, or HIIT, is just as beneficial as – if not more than – a longer, moderately intense workout.

HIIT involves short bursts of exercise with brief (30 to 45 seconds) intervals of rest in between. You should be working at maximum capacity and out of breath by the end of the workout, even though it can be as short as seven minutes.

In a study published in the June issue of the journal Certified, scientists compared a group of people on a HIIT plan for six weeks with a group doing traditional workouts for the same period. The interval trainers saw the same improvements in heart health and muscle tone as exercisers in the other group – and they saw most of the benefits in less than half the time.

However, according to a personal trainer, most boutique-gym HIIT workouts, which tend to last about 30 to 60 minutes, aren’t actually high-intensity workouts.

Alice Liveing, who shares photos of her workouts and lifestyle with her nearly 640,000 Instagram followers, is a trainer at Third Space and works with clients of all kinds, including the actress Suranne Jones (“Doctor Foster”) and the British television and radio presenter Maya Jama.

‘There is a stubbornness about me that never can bear to be frightened at the will of others. My courage always rises at every attempt to intimidate me’ This is one of my favourite Jane Austen quotes. I can read her work time and time again and still find something new to appreciate within the pages. After having a day of feeling pretty low, I decided that I can’t let a few negative voices deter me from being authentically me. Because, like Jane Austen (although probably not as articulately) I am writing a story each day. I am learning lessons, making mistakes, choosing to do the right, and the wrong thing. In fact we all are. We’re all muddling our way through the story that is our life. There’s no rule book, no prior manuscript to look to, and reading other stories merely gives inspiration rather than hard guidance. It means that there will be total plot twists, moment of deep sadness and euphoric joy, but at the end of our life we can sit back with a masterpiece we are truly happy with. So yeah, that meant I sat in bed last night and devoured half my mini bar… but who the hell wants to look back with regret thinking, I wish I’d done that but didn’t? So it’s time to dust myself off, remove judgement of feelings of anxiety, and take this new day as a fresh start. Not only does even writing this feel cathartic, but the analogy of writing a story each day sits comfortably with me as a creative spirit. So, thank you all from the bottom of my heart for your kind words. You’re all having a big ass page in my book of my life under the headline ‘THESE PEOPLE ARE AMAZING’ ❤️

A post shared by Alice (@aliceliveing) on

Speaking to Business Insider at Be:FIT London last month, Liveing said she started posting her “health and well-being journey” on Instagram a few years ago while touring as part of the musical “Annie” – she was previously a professional dancer, singer, and actress.

“I was really getting into training and wanted to understand more about my training, so I decided to qualify as a PT,” she said.

When the tour ended, Liveing needed a break from performing, she said.

“My body was just wrecked, and I was exhausted,” she said. “I decided that I would start PT-ing a bit on the side, and I just fell in love with it and enjoyed my time so much that I increased my hours, took on more clients, then was offered a job at Third Space.”

Liveing has written three best-selling books, is a monthly columnist for Women’s Health magazine, and just released a training app.

She works out four or five times a week – but you won’t see HIIT training as part of her regimen.

“It’s all weight training, resistance training, and a little bit of Olympic lifting,” she said.

Drop sets, cluster sets, giant sets.. and the list could go on. Whether you’re working in the fitness industry, are an exercise enthusiast or a newbie lifter, this gym jargon can sometimes feel a little overwhelming, and most people become unsure of what sets are for when. So, I decided to break it down for you and give you a bit of brief information on each in order to help clear up any confusion that may surround this area of your training. 1. Straight sets: These are sets where you do only ONE exercise. These typically (although not exclusively) work best for your big lifts like your squats and deadlifts etc, where you don’t want to further fatigue yourself with a second or assistance exercise. 2. Supersets: These are sets where two exercises are paired together with minimal rest between them. Supersets are great for building muscle, aiding fat loss and for those who are time poor with their training. In terms of exercise choice here, really anything goes. Be it barbells, dumbells, resistance bands or bodyweight, the combinations are endless (and also may depend on where each superset falls within your workout). 3. Tri-sets: As the name suggests, these are sets consisting of three exercises. These sets are ideal for fat loss, muscle building and for people who are time poor and therefore want maximum training efficiency. Again, in terms of exercise selection, anything goes; they can focus on one muscle group, opposing muscle groups, or hit three separate muscle groups depending on the goal or intended training outcome. 4. Giant sets: These are sets with anything above three exercises. Again these types of sets are great for those aiming to achieve fat loss, build muscle and those who have limited time to train in the gym. 5. Timed sets: These are sets where your work/rest periods are timed. They can be used on any exercise selection, and are great for more endurance style training rather than strength work. An example would be doing bodyweight squats for 30 seconds with a 15 second rest. I typically use these with finishers (continued in the comments below).

A post shared by Alice (@aliceliveing) on

She added that while HIIT is certainly very popular at the moment, “true HIIT isn’t what most people are doing.”

Most ‘HIIT’ workouts are actually moderate intensity

“Most people are doing moderate-intensity-level exercise rather than it being high intensity,” Liveing said. “For it to be high intensity, you have to be working at 90% capacity, so you’re literally going into that anaerobic threshold where you’re tapping into that energy system.”

Anaerobic threshold refers to the point during a workout when lactic acid starts to build up in the muscles – something that, during a HIIT workout, doesn’t occur until you’re working at close to 90% capacity, according to Liveing.

Let’s talk cardio ???????? who loves it, who loathes it? I don’t like labelling any form of training good or bad, as with anything in life, we are all unique and what works for one person might not work for another. I personally like to incorporate some cardio into my training and recently teamed up with @reebok_fitness to test out the GT40s treadmill. I went through a few ways in which I’d use a treadmill in my training, from slow steady state walking or an incline power walk to high intensity interval sprints and was impressed with the soft cushioning of the belt that reduces the impact of force and makes for a smooth run! As an added bonus Argos have a special deal on the treadmill at the moment so grab yours whilst you can and try it for yourself! What’s your favourite form of cardio? #ReebokFitness #ArgosUK

A post shared by Alice (@aliceliveing) on

She added that most 45-minute “HIIT” workouts offered by boutique gyms aren’t HIIT at all, as it’s not possible to maintain that level of work for up to an hour.

“It’s MIIT – moderate-intensity interval training – and it’s basically cardio,” Liveing said.

Instead, she suggests: “Reduce the time of your HIIT. You shouldn’t be able to sustain that level of energy for a long period of time; it should be short, more intense, and not a long cardiovascular workout.”

Alice liveingBe:FIT London

One big workout won’t make a difference

Ultimately, Liveing said, it’s important to note that one effective workout won’t make an impact.

“The biggest piece of advice that I give people is that consistency is key,” she said.

“It’s not about coming to the gym with me and smashing out one session a week and thinking that’s OK,” she added. “That is great, but I also want you to be doing that consistently for the next 12 weeks to actually see results.

“One salad doesn’t make you healthy. One pizza doesn’t make you gain weight. It’s the same with training – one workout is great, but you need to have a consistency with that that allows you to have physical change rather than just pinning your hopes on one gym session a week.”

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