What is HIIT ?
HIIT stands for High Intensity Interval Training. It is a relatively long-standing training technique that has gained popularity and awareness in recent years. To understand what HIIT is, you must first know what is meant by ‘Interval Training’.
Interval training is a training method whereby two different intensities of workout are used in the same exercise session. To explain this further we can use running as an example. In general if you were to run a set distance you would set off at a steady pace, and try to maintain this constant pace over the whole distance.
During Interval training the concept is a little different in that you would run fast for a short period and then run slower for a while before running fast for a short period again and so on. Intervals (this usually refers to the higher intensity part of the regime) can be of varying time and intensity and the rest period in between them can vary also.
Varying aspects such as time and intensity of intervals results in different stresses on the cardiovascular system and different physiological changes can be attained depending on the required outcome. Longer rest times in between intervals generally mean each interval can be done at a higher intensity whereas shorter rest periods tend to promote a faster ability to recover.
High Intensity Interval Training is exactly how it sounds. It consists of High Intensity intervals (usually short to allow for a higher intensity) with short, moderately intense rest periods in between. The high intensity and short recovery usually means that the sessions are only short lived, as the body becomes very quickly fatigued, but the overall quantity covered is very high given the high work rate. It is for this reason that HIIT has become very popular, as it allows excellent results to be achieved in a short space of time.
HIIT can incorporate a large variety of different exercise modalities, from cycling to weight training to plyometrics. The exercises chosen are often as a result as the overall goal of the individual performing them. HIIT can be used as a training aid for specific sports, for example basketball or football, or it can be used entirely for the purpose of weight loss or overall fitness.
Why do people choose HIIT?
Although it has been around the athletic and sporting scene for decades, it wasn’t until recently that HIIT became popular amongst the general population. The main reason for this was that it was discovered that as well as making you incredibly fit; HIIT could achieve large amounts of weight loss in a short time.
The term ‘short time’ has two meanings when it comes to HIIT and weight loss. Firstly it refers to the short time it takes to achieve significant weight loss, often only weeks. Secondly it refers to the short time needed to be completed per exercise session.
A typical HIIT session can be completed in as little as 15 minutes, yet give superior benefits when compared to a 30 minute steady, moderate intensity session. This allows people who would otherwise not have the time to exercise, due to busy everyday lives, to fit in meaningful exercise sessions and achieve significant weight loss as well as several other health benefits in a short amount of time.
Can anybody do HIIT?
HIIT is open to almost anybody, although there are a few exceptions, which I will explain later. The main thing when it comes to HIIT is not to jump in too quickly. If you are a novice it is easy to get convinced to start HIIT by a trainer or friends, but it is important that you are prepared and have a baseline level of fitness before you start, otherwise you risk serious injury.
The reason behind this is that HIIT is incredibly taxing on the body. The ligaments, muscles, tendons and skeleton are put under immense pressure, along with the cardiovascular system. Ligaments and tendons are notorious for taking a long time (4-6 weeks minimum) to adapt to increased load, and if you stress them too quickly you risk sprain or even rupture.
If you already partake in medium intensity training it is ok to start a HIIT regime, but if you are a novice, you should spend a couple of months at least building up a baseline level of fitness before getting involved.
Age in general isn’t a barrier and a HIIT regime can be started at any age providing you are in good physical health. The intensity may drop as you get older but the principles remain the same. HIIT is suitable for both men and women and is safe for children (over the age of fourteen) if carried out in a controlled supervised environment.
If you suffer from a chronic medical condition such as heart disease, valve disease, arrhythmia or stroke, or if you are unsure, then you should definitely speak to your doctor before commencing any HIIT regime. In general exercise is beneficial in chronic disease such as heart disease; it is just the intensity that is the issue.
Does HIIT burn more fat than other training regimes?
If you read around you will often come across claims that HIIT is a superior fat burner when compared to. Sometimes you will even find links to spurious studies! Whilst HIIT does burn a significant amount of fat, it is not straightforward to compare it to other exercise regimes.
Some people also claim that the body continues to burn increased amounts of calories hours after a HIIT session as a result of the high intensity. This is certainly a myth as the metabolic rate returns to normal very quickly after any form of exercise and no increased calories are burnt in the hours after exercise.
Where HIIT does win is when it comes to being able to get good results in a short time. If you were to jog for 15 minutes a day, you would likely gain very little in the way of fitness or weight management, but 15 minutes of HIIT would yield much greater results and result in gains and improvement in fitness and body composition.
Can I add HIIT to my current training regime?
As I have expressed, HIIT can be very taxing on the body, and for that reason you have to be careful not to over train. If you are an athlete playing a sport, a HIIT regime a few times a week may be beneficial, but any more than that could lead to poor recovery and fatigue and reduced performance in your sport or even injury.
HIIT can be combined with weightlifting/bodybuilding, but it will almost certainly result in a reduction in the amount of weight you can lift in each session and for this reason if you are a professional bodybuilder or weightlifter you may want to give HIIT a miss.
On the whole HIIT can be combined with most other activities, as long as you listen to your body, be sensible and don’t train through injury.
So I’m ready to start HIIT. What now?
If you have decided HIIT is for you, then you are ready to read on. In the following article I will explain what makes up a HIIT regime as well as giving examples of workouts for beginners to advanced level.