Lyle McDonald

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September 30, 2015

Setting Exercise Intensity

Today, I want to look at the issue of setting exercise intensity in the context of aerobic work, interval training and weight training.  It’s something I’ve been meaning to write about for a while (I think I actually started an article on it years ago) I have included it in other books (notably the Stubborn Fat Solution) and it is going in the woman’s book (still in progress).

Setting Aerobic Exercise Intensity

Traditionally, the intensity of aerobic exercise has been set with heart rate. The typical first step was to estimate maximum heart rate and an old equation of 220 minus age is commonly used. This equation was developed decades ago on a small sample of men and a better equation for women would be 227 minus age in the first place. But the problem is that maximum heart rate can deviate enormously from this value.

That maximum heart rate was then multiplied by various percentages (such as 60-75%) to set training ranges for aerobic activity. And while these types of calculations may be relatively accurate on average, they can be extremely inaccurate for any given individual. Two trainees of the same age, who have different maximum heart rates can end up working at drastically different exercise intensities.

In recent years, performance athletes have started to set their training intensities according to some type of performance threshold. In years past this was called the anaerobic or lactate threshold but most just call it the functional threshold now. This represents the maximum level of effort that can be maintained for about an hour and athletes will typically determine their speed or power output for that time.

Once the threshold is determined, training intensities are then set relative to those thresholds with various types of aerobic/endurance training being at or below the threshold and HIIT falling at or above the threshold. And this is more accurate for setting exercise intensity compared to the old equations since it actually takes the trainees individual response into account. In recent years, it’s been suggested to use this type of threshold to set exercise intensity for most everyone (1).

Read the rest of Setting Exercise Intensity

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