Could 10 Minutes of Exercise Make You Fit ?

Study after study shows that we are in denial about a number of things – our weight and our calorie intake both of which we generally tend to under-estimate. But nothing comes close to the amount by which we over-estimate how active we are.

In a 2011 study published in the American Journal of Preventative Medicine, US adults self-reported close to 60 minutes of daily activity everyday (this includes exercise and also other casual activity such as gardening, household chores or walking to the pantry to pick up a chocolate!). However when activity levels were actually measured using an accelerometer turns out we are active for an average of just 9 minutes daily!

Guidelines provided by the American Council of Sports Medicine and endorsed by other leading health organizations suggest 150 minutes / week of moderate intensity activity (i.e. brisk walking or jogging) – which only 9% of US adults actually achieved. This level of activity is considered necessary to maintain / improve fitness.

So how do we resolve this problem ? A team of exercise physiologists from McMaster University, led by Gillen JB looked to see if we could improve our fitness by exercising for just 10 minutes, 3 times a week (Martin Gibala, a co-author to the study is a pioneer in interval training). After completing a 2-minute warm-up, study participants cycled all out for 20 seconds, followed by 2 minutes of recovery where they cycled at a gentle place. This was repeated 2 more times during that session and then finished off with a 3 minute cool down for a total time commitment of 10 minutes per session.

The results were astonishing – within 6 weeks both men & women saw a significant increase in their cardio-respiratory fitness by ~12%.

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Gillen JB, Percival ME, Skelly LE, Martin BJ, Tan RB, et al. (2014) Three Minutes of All-Out Intermittent Exercise per Week Increases Skeletal Muscle Oxidative Capacity and Improves Cardiometabolic Health. PLoS ONE 9(11): e111489. doi:10.1371/journal.pone.0111489

In addition, they also saw important health benefits – mean arterial pressure (which correlates with blood pressure) decreased by 7%. Insulin sensitivity (important for those with pre-diabetes & diabetes) also improved amongst both groups. 24-hour glucose levels however only dropped amongst men (& not amongst women, which warrants further study).

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This is not the first study to show significant benefits for interval training over continuous exercise – a meta-analysis published in the British Journal of Sports Medicine by Weston et al showed 2x improvement in fitness through interval training compared to moderate intensity continuous exercise. Another review by W Kent in the same publication indicated a 15% increase in fitness within 6 weeks of interval training.

What’s unique in this study is the relatively low time commitment required to achieve this remarkable improvement in fitness and health – a level of commitment that almost everyone should be able to make (with of course brief moments of intense effort). In other words there are no more excuses for not getting fit!


Disclaimer: The content on this blog (and linked websites) is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this blog or linked websites. Reliance on any information provided on this blog is solely at your own risk

What is Fitness ?

I was inspired to create this blog by a recent Show & Tell I did at Quantified Self Boston – sharing data on how I normalized my blood pressure by measuring & improving my fitness. And it seems pretty clear to me that while most people talk about wanting to be fit, very few have actually measured their fitness (or even realize that this is measurable!).

So I decided to pull together some of the resources I was familiar with into one place so that others interested in understanding, measuring, tracking and improving their fitness would find it easier.

We often use fitness in the context of “looking fit” (and I’m guilty of this as much as anyone else). However fitness is not about how much you weight – in fact you can be both fat & fit (though of course if you’ve been sedentary for a while you’re likely to put on weight & lose fitness).

Fitness is also not about how active you are – being active can of course help you stay fit or even improve your fitness but this is by no means a given. The impact on your fitness varies considerably by the type of activity / training you engage in and we will touch upon this in later posts.

Fitness often also tends to imply or suggest muscle strength & endurance. Undoubtedly this important and is often described as “functional fitness”. However for the purposes of this blog and in the interests of creating a common understanding of the term I’m going to separate fitness from muscle strength.

So What is Fitness?

In scientific terms, fitness is shorthand for “cardio-respiratory fitness” – i.e. the ability of the body to supply oxygen to muscles when they become active. (See Wikipedia for a more detailed definition). Another word for this is aerobic capacity. As your fitness improves your arteries & capillaries expand so that your heart can pump more blood (each time it beats) and supply that to the muscles to fuel activity. So in simple terms, the fitter you are – the faster you could run or cycle (though there are other factors that influence your performance including motivation, efficiency etc.).

But the really interesting evidence about fitness relates to its effect on overall health & wellbeing – according to a recent policy statement published by the American Heart Association (Kaminsky et al, The Importance of Cardio-Respiratory Fitness, 2013), fitness:

… appears to be one of the most important correlates of overall health status and a potent predictor of an individual’s future risk of CVD. Besides being perhaps the strongest predictor for CVD and total mortality, CRF (i.e. cardio-respiratory fitness) is also strongly associated with other important health and functional outcomes, including depression and dementia, and their related mortality risks, as well as mortality rates attributable to various cancers, especially of the breast and colon/digestive tract.

In simple terms – you want to stay healthy the one metric you should measure & look to improve would be your fitness.

Over the next few posts I hope to add more information on various ways in which you could measure fitness, various hacks to improve fitness and what science is telling us about the effects of fitness on different health conditions. Alongside I hope to share my own personal data / experience (including from the Show & Tell as well as other information) and I would welcome others who are interested in doing the same.


Disclaimer: The content on this blog (and linked websites) is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this blog or linked websites. Reliance on any information provided on this blog is solely at your own risk.