High intensity training (HIIT) has grown in popularity over the last decade and has come about after a number of years where steady state cardio( aka the same speed or intensity for a set period of time) has ruled king. Steady state cardio has its place and certainly won't do you any harm at all, however if you're plateauing in the gym or struggling to shred that last bit of body fat then it may be time to take a look at what HIIT can do for you.
HIIT tends to represent working for periods of time at a much higher intensity than you might normally for a series of repetitions. The idea being that you break down your total working time into blocks of anywhere between 30 seconds to 3 minutes and work much harder over that time period than you might normally. This gives a higher calorie burning effect, a greater endorphin rush and improves your threshold cardiovascular fitness.
So how does it work? HIIT works by utilizing a phenomenon called EPOC which stands for excess post-exercise oxygen consumption which to simplify for you is basically when your body tries to compensate for the oxygen it has used during exercise. During this period your body is still working and thus we come to the point. The EPOC period that follows HIIT is thought to be greater than during steady state cardio and as such one way that HIIT might work is by keeping the body working for longer.
HIIT is a very versatile training tool though and just because many of the published literature is based on cardiovascular disciplines like running, cycling, rowing and swimming - you can still use HIIT training to your advantage without losing the muscle mass. By super setting (combining exercises), planning circuits, reducing rest periods or using resistance exercises but doing them for time rather than reps you are in a sense doing HIIT. All these interpretations of HIIT will increase the EPOC effect following exercise and burn more calories.
Depending on your state of health and fitness and what you are trying to achieve there are good and bad times to add HIIT to your workouts, I have tried to cover all bases below.
General Fitness
- Integrate immediately! If you're purely looking to get fitter and exercise for your health then there really is no time better to introduce HIIT than today. Especially so if you are in your comfort zone with steady state cardio as your body will love the shock to your training that HIIT will bring.
Body Building
- The age-old battle of the body builder and their muscle mass; you have to be strategic here. You probably don't want to go right ahead and introduce HIIT in a training phase where you are looking to gain weight or are placing a heavy emphasis on maintenance. When you use HIIT it is nigh on impossible not to sacrifice some muscle tissue to strip fat so bear in mind that although of course your body fat % will plummet you may also lose some muscle too. For that reason HIIT fits best into the body building programme that has seen a cycle or two or absolute hypertrophy training.
Weight Loss/Obesity
- This may seem an odd category that I would usher a warning to with HIIT training but this is for good reason. You would be absolutely correct in thinking that HIIT is a great means of burning fat but be careful if you are on an intense calorie restriction diet. HIIT is exactly that, high intensity, and if you're low on energy it's pretty common to push yourself over the edge and become hypoglaecemic when you're doing HIIT - so plan your workouts around your meals and make sure you have some guidance from your trainer or fitness coach.
Sports
- HIIT is fantastic for any athlete playing a sport that requires change of speed such as games players like basketball, soccer, football and hockey. It's also great for sports that require maintenance of body weight and supreme threshold fitness such as middle distance running and cycling. However, you also need to weigh up how much carry over there will be to your sport. If you are playing a sport such as golf or any other sport that is particularly skill based then bare in mind these workouts can be pretty disruptive to your training regimen if you are not used to them. That is not to say that golf is not an athletic sport - just look at Tiger - but you have to weigh up the benefit versus disturbance.
Recovering/injured
- This style of training is exactly as it sounds - high intensity! It probably isn't suitable to be doing circuit or super set style HIIT if you are carrying an injury but something in a more controlled environment such a bike workout or fixed eight machines on body parts separate to your injury site will work well.