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Myth Busting

Finding time to exercise

Tamara Willner
Written by

Tamara Willner

Medically reviewed by

Fiona Moncrieff

5 min read
Last updated May 2024
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Myth: ‘Exercise is only beneficial if it’s performed for long periods of time.’

‘I just don’t have time to exercise’ is a common reason for doing little physical activity. Between jobs, families, and social events, it can be difficult to find time to exercise.

Many people believe that to benefit from exercise, you must perform it for long periods at a time. This thought appeals to the all-or-nothing mindset, where you avoid exercise all together since you only have 15 minutes spare and ‘what can be achieved in 15 minutes?’.

In reality, a lot can be achieved in a short time. Exercising for shorter, more intense periods can provide just as many, if not more, health benefits than longer, less intense exercise sessions. Shorter bursts of exercise are also much more time efficient, which is easier to fit into a busy schedule.

This isn’t to say that long periods of less intense exercise are not beneficial. This type of exercise, such as long walks or yoga, can greatly improve your mental health and quality of sleep. However, when you’re stretched for time, here are some reasons to try and get your heart rate up, even if it’s only 5 minutes here and there.

Weight loss

Researchers from Australia conducted a research review investigating the effects of high-intensity interval training (HIIT) on fat mass, VO2 Max (a measure of aerobic fitness) and insulin sensitivity. Reduced insulin sensitivity results in consistently high blood sugar, which can lead to type 2 diabetes.

The studies included in the review varied slightly in their interventions, but typically participants completed short bursts of exercise for 30 seconds, 3 times a day, 3 times a week for 2-24 weeks. The exercise was either running on a treadmill or cycling on a stationary bike. Findings demonstrated that fat mass significantly decreased, VO2 max increased, and insulin sensitivity increased.

But how does HIIT compare to less intense, longer periods of exercise, such as running? One clinical trial compared:

A) Control group (little exercise)

B) HIIT group (3 weekly 20-minute workout sessions of HIIT)

C) Steady exercise (3 weekly 40-minute workout sessions of cardio)

over 15 weeks and measured the impact on weight. They found that both group A) and C) demonstrated no weight loss, whereas the average weight loss in group B) was over 2kg and significantly more than the other groups. Groups B) and C) showed an increase in VO2 max.

Infographic explaining a trial that demonstrated that HIIT exercise was the most effective for weight loss and insulin sensitivity. A potential explanation for these findings is that HIIT has a positive impact on certain stress hormones released by the kidney that accelerate fat oxidation. This means HIIT might encourage your body to ‘burn’ more fat over regular aerobic exercise. So, any form of exercise can improve your fitness levels but if weight loss is your goal, HIIT could be more effective than longer, less intense periods of exercise.


Key points:

  • All types of exercise are beneficial for your fitness and health.
  • Short bursts of high-intensity exercise are more effective for weight loss than longer periods of less intense exercise. 

Blood sugar control

Blood sugar levels are controlled by the hormone insulin. Insulin regulates blood glucose (sugar) levels by signalling to the body to remove glucose from the blood and store it as glycogen in our muscles and liver for when we need it. If our bodies become resistant to insulin and blood glucose levels are consistently high, there is a risk of developing type 2 diabetes.

The trial mentioned above demonstrated how HIIT improved insulin sensitivity. The more sensitive we are to insulin, the better our blood glucose control.

The changes in insulin sensitivity were significantly related to the changes in weight. Since insulin resistance and weight gain are usually interlinked, HIIT has huge potential benefits for those with prediabetes or type 2 diabetes.

Key point:

  • Short bursts of high-intensity exercise positively impact blood sugar levels.

Heart health

The British Medical Journal published a large meta-analysis of research that compared HIIT with lower-intensity, longer periods of exercise in individuals living with chronic diseases where unhealthy lifestyle was the main contributing factor (such as type 2 diabetes). Results indicated that HIIT was more beneficial to heart health than lower-intensity, longer periods of exercise.

The researches suggested that stiffness of the arteries plays a large part in cardiovascular problems (heart attacks, strokes etc). They suggested that when the short bursts of exercise are of a high enough intensity, it promotes elasticity of the arteries, which in turn reduces the risk of heart attacks and strokes. This was supported by numerous studies in the review that found increased nitric oxide release in HIIT groups, which seems to promote elasticity of the arteries.

Key point:

  • Short bursts of high-intensity exercise may reduce the risk of cardiovascular problems more than longer periods of less intense exercise. 

How to incorporate HIIT into your day

Whether you exercise regularly or are completely new to it, below are some simple ways to include short bursts of exercise into your daily routine.


The moment you wake: star jumps – 1 minute

Mid-morning coffee: wall push-ups (edge of table/kitchen counter/wall) – 1 minute

Lunch break: squats – 1 minute

When you get home: jogging on the spot – 1 minute


The moment you wake: mountain climbers – 1 minute

Mid-morning coffee: push-ups – 1 minute

Lunch break: squat jumps – 1 minute

When you get home: running on the spot – 1 minute


The moment you wake: crossover mountain climbers – 1 minute

Mid-morning coffee: push-ups with clap – 1 minute

Lunch break: lunge jumps – 1 minute

When you get home: burpees – 1 minute

Take home message

  • It is a myth that you have to exercise for long periods of time for it to be effective.
  • Shorter, more intense bursts of exercise appear to be more effective for weight loss,  blood glucose control, and heart health.
  • It is easy to fit in small amounts of HIIT exercise throughout the day by doing as little as a minute here and there.
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Write a response


26 May, 2020

Can you include suggestions for HIT exercises that are suitable for those among us who can’t jump or squat? Or some advice around pre existing conditions would be appreciated. Exercise advice often comes from people who are more able.

Karen Till

16 November, 2019

Just back from 2 weeks holiday and started this new exercise regime this morning. Those mountain climbers are a killer!! Good to have such an achievable routine to ease be back into good behaviour!

Sandra Parish

13 November, 2019

I’m confused as to why you have to warm up for some exercise groups and it’s ok to jump out of bed and do star jumps for HITT sessions. Aren’t you putting yourselves at risk ? – I’m recovering from two recent injuries I wouldn’t want to aggravate anything.

Ruth McCabe

12 November, 2019

Not understanding how the suggested sets of 1 minute HIIT equilateral to 20 mins. Is it important that the 20 m is one session, or are the 1 m sessions adding up at the end of a day to 20 and this dispersed structure works as well? Also how do I get the link onto my laptop for future use

Janet Archibald

3 November, 2019

I really appreciated this as it came just at the right time. I’m living proof that poor sleep affects your weight, motivation. I missed the monthly news letters & this served as a additional pick me up.

Irene Sears

20 September, 2019

I know I could manage the majority of suggestions made.


31 August, 2019

This was a really interesting read. Not preachy – some good points made. For someone like me (lazy and anti excercise) I could actually get onboard with the beginners HIIT suggestions.

Susanna Henley

3 September, 2019

Suggested exercises not great for 63 year old with dodgy knees and leaky waterworks!
Any other ideas?

Deborah Llewelyn

12 November, 2019

Hey Susannah how about swimming?x

Helen Faichen

8 August, 2019

This sounds good, I have never thought about it this way. I will definitely be giving it a try. Thanks.

Irene Sears

4 August, 2019

Just saying the word Exercise tires me out
The 1 Minute hits would interest me and then build up for longer periods. Perhaps also a once a week walk around the local lake.

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