Both entirely different exercise types but is one better than the other? Here’s a brief (not massively scientific!) overview:
HIIT (High Intensity Interval Training)
This form of workout is fast and furious – you can get a whole workout in 15 minutes or so – but the idea is that it’s intense, so that short period is not easy. The aim is to get to 80-90% of your maximum heart rate (MHR) – you find your max by taking you age from 220. You work at this intensity for a very short time and then have a recovery time, before increasing your heart rate back up again for another intense period. Tabata training does this as 20secs hard work, 10secs active recovery for 4 minutes. Other methods could be 2 mins hard work, 30 secs active recovery, but the intervals could be anything – suffice it to say the work part is longer than the rest!
HIIT works you anaerobically and this can put a lot of physical and mental strain on your body. This system isn’t solely fuelled by oxygen (like the aerobic nature of cardio) and uses glucose, from carbs for fuel. It also gives your body the challenge of moving from burning glucose (high intensity period) to burning fats (recovery period) smoothly, which helps your metabolic fitness
High intensity workouts can give you a better ‘afterburn’, that is to say that you carry on burning calories long after you’ve finished the workout. The harder you work the longer you keep burning.
The effect these short blasts offer, means that you really only need to do 3 x 10 minute workouts a week to reap the rewards.
The very nature of interval training is that it’s fast paced, so it’s not a mindful activity and often because you’re just thinking about the intensity/ speed of your movements, technique can often get lost along the way.
HIIT is very intense so you need to have a good fitness foundation before starting this to really see the benefits and not be at risk of injury.
Cardio is a slower more moderate route where your heart rate stays pretty constant, where you should be able to talk while working. This could be anything from jogging to swimming to cycling.
Many forms of cardio can be quite mindful – generally we do cardio for more than 30 minutes at a time and the steady pace gives you plenty of time to think, particularly if it’s just you out in the fresh air cycling or jogging for example. It gives us chance to think about our breathing and this in turn can make it a good stress reliever.
A steady paced workout makes your heart more efficient, getting oxygen to the muscles quicker to give a bigger boost to your cardiovascular fitness and stamina, therefore helping your endurance levels. Recovery will also be easier as your heart isn’t put under as much stress as with HIIT and therefore gets back to normal quicker.
Cardio uses your aerobic system, which is the foundation for daily life – moving about the house, walking etc. It requires oxygen and you find the energy coming from stored fat, unlike glucose with HIIT workouts. That doesn’t necessarily mean you burn more fat, just that your body is more efficient at using the fat. If you want to lose weight you have to spend far more time doing cardio than HIIT to get the same result.
A moderate cardio session won’t give you as long an afterburn as with a high intensity workout.
Cardio won’t build you much strength, power or muscle. Also, doing a single-movement pattern such as running may lead to your loading up on one area of the body and this can lead to injury.
So which is best?
Well they both have their advantages but I would say that if you’re a beginner to exercise, you're best starting with the sustained pace you get with cardio. Once you improve your aerobic threshold you can add in some intervals to challenge yourself.
Both put different demands on the body so it’s unlikely you’ll excel at both, but why not mix and match? Don’t forget that if you stick to one workout with no modifications over a period of time, then you will plateau, so don’t keep doing something if you’re not seeing any results – switch it up!
Ultimately, it’s also down to what you enjoy doing – if it’s a chore or too much hard work, then stop doing it and try something different!
Which do you prefer? I’d love to hear which works best for you and what you like to do.
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