With Coach Kelvin, offering Online Running Coaching for We Run and the We Run Virtual Running Club, and 1:1 Running Coach for Leeds and surrounding areas.
Metabolic Versus Mechanical Training Load
In this little video, I’d like to share some thoughts on metabolic versus mechanical training load and why runners often get hung up on metabolic load and almost disregard mechanical load.
Metabolic load is internal load, which is usually measured by heart rate or a rate of perceived exertion and quite often that’s kind of breathing rate. Mechanical load is measured by pace. We can also bring elevation into that equation as well because running up and down hills applies a mechanical load.
Understanding Zones and Intensity Distribution
We often hear about zone two and only doing a certain percentage above LT one, which is the top of zone two in a five zone model. So people have maybe heard of the 80 to 20 rule where 80% of your running should be easy, 20% is a bit harder. That’s a little bit misunderstood in itself because that’s actually over longer periods of time and not something that you should do each week.
But actually to get that intensity distribution of 80 20, it’s not that easy. You might have to do a couple of harder workouts a week and maybe an amount of moderate running around LT one zone kind of two three, a certain metabolic load.
Why Mechanical Load Often Limits Training
If I’m running at a certain heart rate, so let’s say that’s the top of zone two, LT one will produce a pace and that pace applies a mechanical load and it’s the mechanical load that is the limiting factor in most people’s training, not the metabolic load.
So runners should be mindful of the load that’s in their legs and what they’ve got to do. How the legs feel more from a sort of like niggles and pains and soreness point of view is probably more beneficial in training than worrying about time in heart rate zones.
If you are training, if you are doing an easy run and it’s supposed to be zone one two and it ends up being zone two three, as long as you’re not applying so much mechanical load it’s causing injuries, that is absolutely fine.
Checking and Setting Your Training Zones
One is maybe check in on your training zones, make sure they’re set correctly. Keep an eye on that to make sure that you’re not a million miles away from where you need to be.
Little note as well, Strava and Garmin will not set your training zones correctly. You need to do this by a percentage of LT two or maybe get a coach to set the zones for you.
So check in, make sure you’re somewhere near that kind of 80 20 split over longer periods of time. And that’s more sort of months and years than it is for individual weeks of training.
Balancing Load for Better Progress
And then as long as you’re handling the load mechanically so you’re not getting too many niggles or injuries, it’s absolutely fine to push a little bit of heart rate whilst you’re training.
So I hope that makes some sort of sense and if you’ve got any questions, please pop them in the comments below. And for now, happy running.
