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29 Jan 2009

Running,weightloss, heart rate
I would like to loose weight by running(inconjunction with light strength training), I have heard that you should try and control your heart rate for optimal/effective weight loss,ie you cant just jump on the tread mill and go for it, there has to be a level of control. Is this true? or can I just run for 20mins and keep increasing time and speed? I am a 25yr old female, weight57kg height 1.57m. I am hoping to loose 5kg in 5 weeks. how should I run based on heartrate and weight loss goals. Also, I dont want to burn out but do want to push myself to achieve goals. I look forward to the reply!
Thanks
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Expert
FitnessDoc
fitnessdoc

01 Jan 0001

HI Keen

There is a great deal of misunderstanding regarding the use of heart rate when it comes to training for fat loss. It is true that at lower exercise intensities, fat is used preferentially instead of carbohydrates, and so in theory, the rate of fat loss is greater at lower intensity. This has led to the idea that training at certain heart rates are better for fat loss. While there is some truth in this, it’s not necessarily the best way – you see, the important thing for fat loss is not so much how much of the energy comes from fat, but rather the total energy used during exercise. This is the way to optimize total fat loss, and this occurs at a slightly higher heart rate.

So, basically, the range for fat burning will be somewhere between 70 and 85% of maximum. Anything higher than this probably does burn more fat, but the problem is that it’s really hard to exercise for long at this high intensity, so the total fat used is lower. Therefore, the aim should be to exercise for 40 to 50 minutes, at a moderate intensity – it just so happens that for most people this is between 70 and 80%. I know that currently, you're at 20 minutes which is perfect. However, I think over time, as you get fitter, you can look to increase this to about 40 minutes. The intensity is dictated by your perception, not necessarily your heart rate.

If you find that it’s really difficult to lift your heart rate, or that your heart rate is too high, but that you can easily keep going for this long, then don’t worry about heart rate anymore – it’s not like you burn less fat. The main thing is to do a session that you can complete feeling tired, but not exhausted, having lasted for 40 minutes
or more.

One last thing - I have to encourage you to avoid getting stuck on numbers, particularly weight. Losing 5kg in 5 weeks when you weigh only 57kg to begin with is really hard. My advice is to focus on fitness - if you get fitter, you'll see progress that counts. But if you focus on those 5kg, then you'll struggle.

Good luck

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