High intensity interval training (HIIT)
Squeezing a week's exercise into a single hour sounds too good to be true, but if you're short on time or find hours in the gym boring, then high intensity interval training (HIIT) might be for you.
By alternating short, intense bursts of exercise with periods of gentler exercise, you get a really effective cardio work out, as well as temporarily upping your metabolism, in a lot less time than it would take if you went at a moderate pace.
It's among the most efficient ways of increasing your fitness levels and stamina, and losing weight, but (there had to be a but) when you're working hard, it is very hard.
You can apply HIIT to almost any form of cardio workout in the gym, or at home. As long as you alternate between pushing yourself as hard as possible and gentle rest periods in between, it's likely you'll start to notice improvements within a short space of time.
"I did interval training with a personal trainer twice a week, and it had a great effect on my body, particularly my legs. I lost weight and toned up quite quickly. It also stopped me from getting bored, and because the high intensity bursts are so short it's achievable!" Susieloo
How HIIT works
HIIT is all about the work-to-rest ratios, which can vary from 1:2, 1:3, 2:1, or 1:1, and can be in bursts of seconds or minutes.
An average HIIT session will last 20 minutes (not including a short warm-up) done three times a week. It will involve pushing yourself to around 90% of your absolute maximum for 30 seconds, then 'resting' for 60 seconds, for instance.
It will thoroughly knacker you, but after 20 minutes you can put your feet up (but do remember to stretch first).
How to start HIIT
Find a fitness programme or system that uses ratios which are right for your fitness level. If in doubt, head to the Talk boards where lots of Mumsnetters discuss which programmes or ratios they prefer.
To ensure you're doing HIIT as efficiently as possible, find out your maximum heart rate (MHR) using a heart monitor or machine in the gym.
Then figure out roughly how hard you should be exercising to be at 90%-100% of your maximum ability and aim for that during your high-intensity work periods. Your rest periods should be around 50% of your MHR.
One of the easiest types of HIIT is alternating running with jogging, or jogging with walking if you're less fit. Couch to 5k uses this method very effectively and tapers it up until you're comfortable running 5k or more. You can download apps like Runkeeper or the NHS Couch to 5K running plan to keep track.
Other HIIT is home aerobics, using a skipping rope or trampoline, or in the gym use cardio machines, such as the bike, cross-trainer or rowing machine.
Tabata is HIIT's faster, more blisteringly-exhausting cousin, and has come under fire from fitness experts as being too dangerous to use if you don't already have a high level of fitness. Tabata uses the same principles as HIIT, but condensed into just four or five minutes of pain.
If you have high blood pressure, cardiovascular problems or are pregnant, or have any other concerns, definitely consult your GP before starting a Tabata programme.
"You do 20 seconds at your maximum (eye-popping) effort at top speed. Then 10 seconds of very slow recovery. Repeat this eight times over four minutes. The first two or three repetitions don't feel too bad, but it builds up so by the end you should be dying...!" notyummy
Dr Michael Mosley and co-author of Fast Exercise, Peta Bee, joined us in MNHQ to talk about the practice and benefits of high intensity training.
Catch-up on their webchat and watch the video below where they show us some examples of fast exercises you can fit into your day.
- Diet and fitness homepage
- Intermittent fasting - the 5:2 Diet
- New to exercise? Join the discussion on Talk