We wish we had a concrete answer, but as you may have guessed, it’s not that simple. First and foremost, everyone’s body is different and the amount of training stimulus one can handle is dependent on a multitude of factors (some of which fluctuate each day) including training and injury history, genetics, stress, recovery, nutrition and more. Secondly, carrying out high level studies over long periods of time to determine these parameters is nearly impossible due to the difficulty of controlling training of large groups of runners well enough to meet standards of scientific rigor.
Over the last decade, many studies have tried to predict injury risk via prospective or forward looking studies, and there have been mixed results. These mixed results may be related to different experience levels and individual injury histories and abilities of runners in each group. In addition there have been studies that have placed runners of similar experience levels into groups, in attempts to determine which type of training program is best to reduce injury risk.
If we take a closer look at one of the studies by Mitchell Ruah from the Journal of Orthopedic and Sports Physical Therapy, which looked at high school cross country runners’ summer training habits and following in-season injury risk, we discover some interesting findings. Most significantly, in season injuries occurring within the first month were more common among those who did not frequently alternate short and long mileage on different days and/or who ran 8 weeks or fewer during their summer off-season training. Another recent study from the International Journal of Sports Physiotherapy found that recreational runners with an average of 5 years experience who participate in less than 2 hours (total) and less than 2 sessions of running per week are at a higher risk of injury than their counterparts who run more frequently and for more overall time per week.
These findings are helpful, in that they help us to understand that variation and consistency in training are key factors when reducing injury risk. However, when determining what specific training modalities should be used, you must keep in mind the value of specificity, without sacrificing variability.
At first this may seem contradictory, but here’s what we mean is this: If you want to run fast and injury free, running must be an integral part of your training, however if you want to run a 5k, you shouldn’t only run 5k’s each time you train. Runs of different distances and speeds, in different external environments should be used. The proportion of ‘fast’ runs (or hard miles/workouts) to easy runs will depend on your goals, experience level and injury history.
One of the most common mistakes we see novice runners make, is running for the same amount of time, on the same route for every run, and then after trying higher level variations or running a race, they report onset of pain or discomfort. Running must be a progressively loaded and variable activity, especially for novice runners. Supplementing running training with cross training to decrease load on your lower extremity joints and maintain aerobic capacity as well as strength training to improve running efficiency can assist, but the bottom line is you have to run to improve your running performance.
So how much and how hard should you run? A recent retrospective study looked at the self-reported training programs of over 600 marathon runners and found that approximately 10% of runners sustained an injury during or shortly after the marathon that held them out of their typical training for at least 2 weeks. After controlling for confounding factors, the authors concluded that running less than 30km (18.6 miles) per week leading up to the race led to a 2x increase in injury risk when compared to those running between 30 km (18.6 miles) and 60 km (37.28 miles) per week. There was no increase in injury risk found for those running over 60 km per week.
It is important to keep in mind that these studies included runners of all levels and although statistical analysis controlled for factors such as injury history and experience, that every individual we treat is different. Each training plan should be well thought out with the help of the athlete to develop a plan that utilizes their strengths, improves on their weaknesses and is attainable.
So what should we do with the current knowledge?
Novice runners should start out slow, and have structure and consistency to build a base.
Want to run fifty miles per week? Not so fast, literally. This is definitely an attainable long term goal, however slowly build up to this goal if you haven’t run before or recently. How long will it take? That answer is very person dependent and requires individualized programming and a good relationship with a coach.
Have a plan and adjust as necessary. Don’t wait until something already hurts to make a change or get help.
Run training plans should include variation.
Just because one person says something worked great for them does not mean it is right for you.
Listen to your body and trust in the plans you, your coaches and other providers make.
Don’t be afraid to ask for help. Improving running performance while maintaining low injury risk can be tricky even for experienced runners and coaches
Interested in online run coaching? Shoot us an email here
Malisouxa, L. Nielsen, RO. Urhausena, A. Theisena, D. A step towards understanding the mechanisms of running-related injuries. Journal of Science and Medicine in Sport. 2015 (18). 523–528.
Rasmussen, CH et al. Weekly Running Volume and Risk of Running Related Injuries Among Marathon Runners. IJSPT. 2013. 8(2). 111-120.
Rauh, MJ. Summer Training Factors and Risk of Musculoskeletal Injury Among High School Cross-country Runners. JOSPT. 2014. 44(10). 793-804.