The goldilocks threshold of soft tissue stress
(almost always the case for new runners) then you will only be as strong as your weakest link, and wherever that is, that will be the first thing to go.
In the first few weeks of a new exercise regime, you need to bear in mind that your tendons and ligaments are at least 10 to 14 days behind how strong you might be feeling on any given day.
And if you’ve been careful, and made it through the first fortnight without imposing too many new demands on tendons that are still struggling to adapt, there is another process that is even slower.
Since the 19th century, we have had Wolff’s Law to tell us that our bones adapt over time to increased loading. Imposing new demands on bones stimulates them to remodel. Called mechanotransduction, bones convert the physical indicators of the forces and stresses placed upon them into chemical ones that stimulate the bones to repair, first by breaking down their existing structures and then by rebuilding stronger ones. But this is a much slower process than with soft and connective tissues.
While it may be surprising to learn that two weeks into your new training schedule your bones are basically still those of a non-runner, the news is actually worse than this. Bone remodelling requires that some of the structure is destroyed (by a cell called an osteoclast) before it can be rebuilt.
So, during your third week of running, feeling fitter and stronger, with some soft tissue adaptation beginning to take place, your bones are for a short period actually weaker than when you first started. By the fourth week, your bones will have succeeded to adapting to your first week’s run and so will be a little stronger. But they are always going to be a few weeks behind because contrary to popular belief running is very good for our bones, but density adaptation is comparatively slow.
With these processes in a constant and unsynchronised cycle, the new jogger has to be vigilant in not running away with their newfound fitness straight into a stressfracture. If you have just taken up running it is worth thinking about the Goldilocks Threshold, and remember that no one has ever given up or got injured because they did too little. The clearest feedback that your body gives you while running is that of your immediate cardiorespiratory experience. And for every run you do, this will improve, but you must avoid entirely the idea that cardiorespiratory ability is an indicator of your overall fitness – it isn’t. It is only the tiniest tip of the iceberg of what is going on in the body.
While you’re just hitting your stride, your body is punishingly hard at work doing some miraculous things under your skin to adapt to your change of lifestyle; so be kind to yourself, take it slow, enjoy it, give your body the time and space that it needs, and you will be much more likely to make it to February.
Cregan-Reid is a reader in Environmental Humanities and Author of ‘Footnotes: How running makes us human’, University of Kent. This article first appeared in