TRAINING TO REDUCE BONE STRESS INJURY RISK
After one bone stress injury (BSI), your risk for another increases. The reasons for this vary and likely include a unique combination of factors for each individual, which makes risk reduction person-specific and a bit of a challenge.
Fortunately, there are certain principles of bone loading and remodeling that can inform training to reduce risk for another BSI.
If you’ve struggled with recurrent bone stress injuries, having a coach who’s knowledgeable about this kind of injury & individualizes your training with your history in mind makes a huuuge difference in keeping you healthy while still getting faster. It's also important to have a team to help you evaluate hormonal status, nutrition and bone health.
Here are some training themes to reduce your risk of BSI:
BSIs occur due to training errors. Rapid changes in training such as quick spikes in mileage or speedwork increase injury risk, but each individual has their own tolerance to training changes - so one general rule (e.g. the 10% rule of increasing mileage) can’t be applied to all runners to reduce running-related injuries.
Since personal BSI risk depends on a complex interaction of workload, injury history, bone health, energy availability, hormonal status, and more, the best training plan for a runner with BSI history is an individualized one.
Off-the-shelf training plans may not be the best route for those of us with a propensity to overdo it and higher risk of recurrent bone stress injuries - finding a coach to create a plan specific to you, your history and your goals can improve your chances of staying healthy & consistent with training.
Periodize Training with Intentional Deload & Rest Weeks
Bone cells are sensitive and respond to changes in loading - so activities that load bones through both muscle contraction or impact (such as ball sports, plyometrics and strength training) stimulate bone-building processes.
Distance running, unfortunately, does not contribute to building healthy bones. Since bone cells desensitize to repeated loads, they stop responding after a few minutes of running and the bone-building stimulus we see from other activities is absent. Not only do bone cells stop responding during each run, but they also lose sensitivity over the course of a training block. This means their ability to adapt & re-build decreases with the same and/or a greater training stimulus, potentially increasing injury risk as your race gets closer.
With that said, we can intentionally plan rest to ‘reset’ the bone’s ability to adapt, in a way. Rest periods allow bone cells to regain sensitivity & more optimally respond to load, making rest a crucial part of training particularly in those with a history of BSI.
Based on the timelines of bone breakdown & remodeling as well as research on bone cell resensitization, current recommendations for deload weeks & relative rest in runners susceptible to BSI are:
At least 1 day off from running per week
Approximately 1 week off from running every 12 weeks
Deload with a drop in running volume every 4th week
Progress Duration before Intensity
Bones fatigue faster with high-intensity training than with low-intensity, longer-duration training - so running faster paces puts you at higher risk for BSI than running more miles at a slower pace.
It appears that running volume and BSI risk have a linear relationship - as you run more miles, the amount of loading your bones undergo & subsequent risk of BSI increase at the same rate.
In contrast, running intensity and BSI risk have an exponential relationship - as you run a little bit faster, your BSI risk increases at a higher rate. So bone fails more quickly & you have a greater risk of bone stress injury with higher intensity training than with lower intensity, long duration training.
The takeaway: It’s safer to increase training volume than intensity when it comes to mitigating risk for BSI. Limiting and very conservatively progressing speedwork is something to strongly consider if you’re at higher risk.
If you’re looking for help training intentionally to reduce your risk of BSI or seeking help with BSI recovery, let’s chat - schedule a free phone consult below!
Warden, S. J., Edwards, W. B., & Willy, R. W. (2021). Preventing bone stress injuries in runners with optimal workload. Current osteoporosis reports, 19(3), 298-307.