What the research says
The theory that running is bad for your knees is not backed up by science. In fact, the opposite may be true
Research published in the European Journal of Applied Physiology in 2016 looked into the physiological mechanisms that running may trigger to protect the knee joint.
What the researchers found was that 30 minutes of running induced positive changes in markers of both inflammation and cartilage turnover compared to an equivalent duration of sitting. The study was conducted on a small sample of healthy male and female runners.
And an earlier study published in the Archives of Internal Medicine examined the capacity of a group of runners to perform a variety of functional tasks over a 21 year period.
It was found that both male and female runners maintained significantly lower disability levels compared to non-runners at all time points throughout the study.
It seems reasonable to conclude that a moderate amount of running is unlikely to harm healthy knees, and may actually offer a protective effect against degenerative conditions.
Training vs recovery - getting the balance right
Why you get tired when you run
Keep on running
The following strategies can help to minimise any damage to your knees from running:
Manage your weight
Keep your weight down if you are a regular runner. Progress gradually from walking to running if you are attempting to lose weight
Use soft surfaces
Make sure some of your running training is performed on softer surfaces such as grass and sand. Deep water running (while wearing a buoyancy vest) is also a challenging workout that places minimal stress on your knees
Don't just be a runner
Make sure to include other cardiovascular activities in your training program, such as swimming, paddling or cycling. This can maintain your fitness while giving your knees a break from the impact of running
Choose good shoes
Look for shoes specifically designed for running that provide good cushioning. It's also important to be aware that shoes lose their shock absorbency over time, so replace them regularly if you are clocking up a lot of kilometres
A running coach can examine your technique, and make suggestions that can prevent injury and potentially improve your running efficiency
Don't ignore pain
If you are experiencing knee pain, or have any injury concerns, seek professional help. A physiotherapist can diagnose problems and help to prevent future trauma
Strengthen and stretch your leg muscles
By strengthening and stretching the muscles around the knee, you can increase stability and prevent injury
Hyldahl, RD et al. Running decreases knee intra-articular cytokine and cartilage oligomeric matrix concentrations: a pilot study. Eur J Appl Physiol. 2016; 116: 2305-2314.
Chakravarty EF et al. Reduced disability and mortality among aging runners: a 21-year longitudinal study. Arch Intern Med. 2008: 168; 1638 - 1646.