This is from my weekly email newsletter but I republish it here for sharing and referencing. If you're not already a subscriber you can join below:
Happy Tuesday!
Today's letter is for anyone who likes to exercise, play sports, compete, or otherwise stay active on a regular basis. Maybe you love to run, cycle, lift weights, practice yoga, or swim? Maybe you've set some goals as part of your New Year's resolutions?
Whatever it is that you love to do, you can't do it if you're hurt or injured.
Getting injured sucks. Fortunately there's a few things you can do to get hurt less. Unfortunately they're not always super intuitive.
If you've been exercising for awhile you've probably injured yourself at least a few times. For a lot of us, this happens when we push beyond what our body is capable of handling at that particular time. Sometimes, when we're just feeling good, or when we train without having properly recovered first, we do more than we should and this can lead to injury.
If you're like me, these incidents are infuriating and stressful not only because of the pain but also because in retrospect they always feel so preventable. Afterwards I'm always thinking, "you knew you shouldn't have done that but you did it anyway ... " or, "you knew you were feeling off but you ignored it ..."
At the same time, however, I know that one of the best ways to reduce my risk of injury is to improve my body's ability to handle physical stress. The only way to increase my capacity for physical stress is through training.
But there is a fine line between pushing hard enough to build resilience and pushing so hard I end up injured.
As we get older and our bodies accumulate more wear and tear, the line dividing healthy exercise and dangerous physical stress narrows. At the same time, the consequences of crossing that line can be more severe.
So how do we strike this balance? How do we build physical resilience to help us stay active and prevent injury without causing injury in the process?
As part of my work with Tether Health, I spend a lot of time thinking about how to help active people not only rehab injuries but prevent them as well. As part of this we need to understand how and when injuries tend to occur. Recently, my team identified a fascinating study which looked at this exact problem.
In the study, the researchers found that the most important factor in determining injury risk was the ratio of physical stress in any given session to the average training stress over the preceding 3-6 weeks.
So what does that mean exactly?
In any given training session you can increase physical stress through increased weight, volume, or intensity. Because each person is physiologically different, it is easiest to measure physical stress in terms of the "perceived effort".
Let's suppose, for example, that you're prepping for a race. The researchers found that injury on the day of the race is most likely to occur in one of two scenarios.
When the average stress (as measured by perceived effort) of your training sessions for the weeks leading up to the race was:
In the first scenario you are susceptible to injury because you are fatigued. In the second scenario you are susceptible to injury because you are unprepared.
How do we use this knowledge to keep improving our performance and build resilience without injury?
1) Training too much/intensely increases your fatigue and therefore increases your risk of injury as well. This is why making time for a proper recovery is so important to prevent injury.
2) If you take a longer break from training you have to be careful when starting up again. Your risk for injury actually increases the longer you're out. This is called deconditioning.
Note that the same logic applies whether you're already super fit and training for a marathon, or just getting started and training to run a 5K. The absolute amount of stress doesn't matter.
What matters is how hard you are pushing yourself relative to your physical capacity i.e. your perceived effort.
Here's two tips which you can use to help you stay in the sweet spot.
After each training session (or even each set if you wanna get super granular) make a note of how "hard" the session felt. In other words, what was your "perceived effort" to complete your routine. Usually a number between 1-10 is best.
Over the course of 2-3 weeks you want to average around a 7. If you're consistently at a 9-10 you're probably too fatigued and need to cut back. If you're consistently at a 5-6, you need to increase weight, volume, or intensity.
If you do have to take a break for more than a week, either because of an injury or because of life stuff, work, travel etc. Drop your weight, volume, or intensity by 5-10% for every week you skip.
Even if you can't feel it your body is deconditioning and if you jump back in too quickly you can easily re-injure yourself.
That's all for now! Hopefully this gives you all some rough guidelines for how to think about injury prevention while training. Let me know if you have any questions and good luck with your new year's resolutions :)
Cheers,
Nick