HIIT and healthy
- Overview
One of the most common reasons people give for not doing regular exercise is: “I don’t have enough time.” It’s currently recommended that adults do at least 150 minutes of moderate-intensity, or 75 minutes of vigorous-intensity activity per week in order to see health benefits.

Whatever form of exercise you choose to do, be it running, cycling, swimming or classes, that’s a lot of time to dedicate to fitness.
But if you can’t reach the recommended time threshold, is there another way to achieve similar improvements in fitness, or is all lost?
Don’t throw in the towel just yet. There is growing evidence to show that three 30-minute HIIT (high-intensity interval training) sessions, including at least 10 minutes of high-intensity activity, could be as good as exercising at a moderate level for 150 minutes per week.
What does a 30-minute HIIT workout look like?
The three stages of any workout still apply, regardless of how long or intense the session is: warm-up, exercise, cool-down. Stages one and three are non-negotiable. Skipping either could cause injury, stiffness and reduce the efficacy of your hard work in between.
We’ve used the example of cycling, but most aerobic exercises performed at an intense level for short intervals would work.

Warm-up (0-5 mins)
- Begin jogging or cycling at a steady pace
- Gradually increase your speed every minute until you are slightly out of breath but can still hold a conversation.
Intervals (5-25 mins)
- Cycle for 60 seconds as fast as you can on high resistance
- Recover for 60-90 seconds at a low speed and low resistance
- Repeat intervals and rests for 20 minutes
During the intervals, your aim is to reach 90% of your maximum heart rate – you should be out of breath and struggling to maintain the effort. If you don’t have a heart rate monitor, you can learn about rating perceived exertion according to how you feel.
Cool-down (25-30 mins)
- Jog or cycle at a steady pace for five minute
- Stretch out your legs and upper body.
Definitive proof?
HIIT-based exercise is still being studied, and nothing is ever really definitive in the world of fitness research. The good news is that the evidence base supporting its efficacy is both robust and growing.
Yes, doing three workouts per week that include at least 10 minutes each of high-intensity interval work is very likely to improve your health and fitness, whether you’re already fairly healthy or could do with being fitter. Your aerobic capacity will increase, and the associated benefits of being more active will make you feel great.
However, there is no absolutely definitive advice that will suit every individual’s needs and abilities. If you’re already doing the recommended 150 minutes of exercise per week, we aren’t suggesting that you cut back.
If you’re able to include three HIIT sessions into your existing weekly exercise schedule, then try it for a few weeks and see how you feel. If you’re not doing much exercise at all, a few HIIT sessions would be a quick and easy introduction to exercise to suit a busy life.
Like the idea but don’t know where to start? A few sessions with a Personal Trainer would get you on the right track, or you could look out for HIIT classes at your local gym.
Before you engage in a
new exercise or nutrition plan, we advise you to discuss your goals and plans
with your health care practitioner. They will be able to assess your physical
state and discuss the suitability of your plan, taking into account any risks
or underlying conditions.
Last updated Thursday 17 January 2019
First published on Tuesday 21 March 2017