Garmin Connect users may notice a new metric hidden away within Training Status, with the company quietly rolling out 'Chronic Load' over the last few days.
The insight is tacked onto the Acute Load menus within Connect, and it essentially beefs up this area with more information to help you manage your condition.
We've spoken to Garmin about the feature, and got inside word on what it does, and the devices that are supported.
Whether you're concerned about sustaining injuries as you up your training load, or you're worried about the cumulative effect of some time off, we think Chronic Load has the potential to be pretty useful. Let's dive into the details.
What is Garmin's Chronic Load?
Unlike Acute Load, which is a measure of the short-term cumulative sum of your training, Chronic Load instead broadens the scope and focuses on a longer period.
A Garmin spokesperson told Wareable:
"We have been recording chronic load for some time, as it is used to highlight the green optimal range of acute load."
According to Firstbeat, the Garmin analytics arm behind the metric, Chronic Load takes into account the last 28 days of training. Acute Load, meanwhile, only focuses on the last seven days.
It's still represented as an overall figure in the same way Acute Load is, though, and can be tracked in a similar way through the Garmin Connect graph. It all means you'll still receive an indication of whether your load has changed too quickly, and whether that figure is in a healthy range.
As shown above, this is also applied to your historical data (though, at least in our case, certain four-week ranges don't have the option to apply Chronic Load).
Which devices support Chronic Load
Garmin also told Wareable:
"Products that are compatible with Chronic Load are: Forerunner 955, Marq Gen 2, Epix series, Fenix 7 Series."
So only the owners of top Garmin smartwatches will see Chronic Load listed in Garmin Connect.
How is Chronic Load calculated?
As it does with Acute Load, Firstbeat and Garmin use TRIMP to quantify each session and present you with an overall short-term figure.
TRIMP largely measures load through heart rate, though the length of a session is also taken into account.
Nothing really changes when it comes to Chronic Load - only that the seven-day TRIMP calculation is expanded to include four weeks instead of just one.
How to use Garmin Chronic Load
This is the kicker - and something that's not actually detailed within Garmin Connect.
While Acute Load is pretty easy to understand, as you'll get a clear marker of when it's 'Low', 'Optimal', 'High' or 'Very High', and there's also the knock-on this has on your overall Training Status, Chronic Load is simply represented as a graph at present.
Given that this data isn't included in Training Readiness just yet, either, and Firstbeat/Garmin hasn't yet introduced the 'Acute:Chronic Workload Ratio' shown above onto a Garmin device, you'll sort of have to work this out manually.
As explained by Firstbeat, referencing a study on injury prevention, the sweet spot for this relationship is when your Acute and Chronic loads are close to equal (and the ratio is 1.0). So, using the examples above, the left-hand value of 1.2 sits in a healthy zone, as both Acute and Chronic loads are well managed.
The right-hand value of 3.5, though, where a user has ramped up their Acute Load despite having a relatively low Chronic Load figure, is at a much higher risk of injury.
Firstbeat explains how the risk of injury begins at around 1.5 (something similar to the middle example shown above) and increases further the higher the separation gets between Acute and Chronic.
The easiest way to interpret this relationship is to touch the graph in Garmin Connect and see how both figures match up. The closer those numbers are to each, the better.
In theory, you should also be able to ramp up your Acute Load up by a relative value of 0.3 and still not run the risk of injury.
Find Chronic Load in Garmin Connect
After checking several Garmin devices, Chronic Load doesn't appear to be available to view on the watch itself. However, it is available in Garmin Connect.
All you need to do is head to My Day > Training Status > Load > Acute Load > Chronic Load.
After selecting that Chronic Load tab, the graph will overlay orange boxes each day to indicate where your load sits against your Acute Load.
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