Knee pain is the most frustrating roadblock for dedicated runners. Whether you're training for your first 5K or preparing for a marathon, knee injuries can sideline your goals and leave you searching for answers. We sat down with Tom Harrison, a specialist physiotherapist at PacePhysio in Hove, East Sussex, to get expert insights into preventing and managing the most common running-related knee problems.
While PacePhysio helps runners recover from everything from shin splints to tendon pain and bone stress injuries, we focused our discussion on the issue they see most frequently: knee pain. Tom shared invaluable insights into early warning signs, prevention strategies, and targeted exercises that every runner should know.
Understanding Why Knees Hurt When Running
The knee is the most common area of the body to experience running injuries. According to Tom, the root cause is surprisingly simple: "Any injury is going to be a consequence of this simple formula of the load you're putting through a tissue is exceeding its capacity."
Think of it as a balance scale. When your knee's capacity to handle stress exceeds the load you're placing on it, you're in the safe zone. But when that load exceeds your knee's current capacity, injury becomes inevitable.
"That little table on the left is where you've good capacity that's exceeding the amount of load, the amount of stress you're putting through that joint, so we're happy runners when that happens. When we start to get injured, it's when the capacity that we have doesn't match that load that we're putting through it."
The Two Most Common Running Knee Injuries
Runner's Knee (Patellofemoral Pain Syndrome)
Runner's knee, technically known as patellofemoral pain syndrome, affects the area around and behind the kneecap. This condition occurs when the kneecap doesn't track properly in its groove during the bending and straightening motion of running.
Runner's Knee Symptoms
- Pain around or behind the kneecap
- Aching during or after running
- Pain when walking up or down stairs
- Discomfort when sitting with bent knees for extended periods
- A grinding sensation in the knee
IT Band Syndrome and Knee Pain
IT band syndrome affects the iliotibial band, a thick band of tissue that runs from your hip to just below your knee. When this band becomes tight or inflamed, it can cause sharp pain on the outside of the knee.
As Tom explained: "We touched upon the two main injuries, which is normally IT band pain or patellofemoral pain, which is more like runners knee, and they're slightly different, but the management is actually very similar between the both."
Running Factors That Increase Knee Load
1. Overstriding and Low Cadence
One of the biggest contributors to knee pain is overstriding - landing with your foot too far in front of your body's centre of gravity.
"One of the key things I think is this over stride," Tom explains. "So you see that picture on the left where they're they're landing with their foot quite far in front of their centre of gravity, compared to that runner on the right where they're landing under their body? For that runner on the left, the force from the ground is just going to be coming up to that knee. Whereas the runner on the right, the force is going to be just evenly distributed up the body."
On the topic of cadence, "over striding and cadence are just so related. If you're over striding, you're taking big, long steps each time you run, so you're going to be taking less steps per minute than someone who is taking quick, short steps with snappy landing under their feet. Cadence refers to how many steps you take per minute. So higher cadence is generally better. Lower Cadence is generally a sign you might be over striding and putting more force on your knee."
How to Fix It:
- Check your recent runs on Strava or your preferred running app
- The average cadence is 164 steps per minute, but this varies by height and running style
- Increasing your cadence by 7.5-10% can significantly improve pain and reduce load on the knee
- Try running to a 170/180, etc. BPM playlist on Spotify to naturally increase your step rate
2. Running Downhill
Downhill running significantly increases the load on your knees. If you're experiencing knee pain, avoid downhill routes during your recovery.
Alternative: Consider running on a treadmill with a 5% incline, which has been shown to reduce load on your knee by 20-25%.
3. Running All Your Runs Too Fast
Increasing both weekly volume and speed work simultaneously significantly increases injury risk at nearly every joint. Build up easy mileage for 4-6 weeks before introducing speed work or challenging terrain.
Mechanical Factors Affecting Knee Health
Patella Tracking Issues
"Essentially what we're looking at on that picture is every time you're running, you're bending and straightening your knee, and your kneecap is just sliding on a groove," Tom explains. Some runners experience kneecap malalignment, where the patella doesn't track smoothly in its groove.
Solution: Consider taping your knee for runs. "For example, when I was training for a marathon, I did start to get a bit of diffuse knee pain. I taped it up before those long runs and it just meant I could do 5K extra before it kind of came on."
Hip and Ankle Stability
"Your knees are kind of like the centre point for other issues in your body. So if you don't have hip strength or ankle strength or stability around there, it's just going to place more stress on your knee."
Poor stability above and below the knee increases demands on the knee joint itself. For this reason it's important to work on wider lower body stability exercises.
Footwear Considerations
Running shoes with high heel drops (the difference between heel and toe height) can increase stress at the knee joint. Consider shoes with a heel drop under 6mm.
In response to a question about shoe rotation, Tom also recommends rotating between 2-3 pairs of shoes: "A lot of the research would suggest having a rotation of two to three pairs of shoes, exactly like you say. It's best for injury reduction because they'll have slightly different dimensions that are going to influence different muscle groups."
Knee Strengthening Exercises for Runners
Building strength around the knee is crucial for injury prevention. Focus on these key areas:
1. Hip Abductor Strength
These stability muscles are incredibly important for knee health. Perform side-lying leg lifts, aiming for 10 controlled repetitions lifting the top leg.
2. Calf Strength
Your calves absorb over 50% of the force when you land and propel you forward. They're essential for knee support for running.
Target: 25 reps for females, 30 reps for males of single-leg calf raises
3. Quad Strength
Your quadriceps attach to your knee and handle forces around 5 times your body weight when running.
Exercise: Single-leg wall sit
Target: 30 seconds for females, 45 seconds for males
Power and Plyometrics
Don't forget explosive exercises! "Our knees and lower limb have to act as springs to move of us forward quickly when running." Include jumping and bounding exercises in your routine.
Stretching Exercises for Runner's Knee
While strengthening is crucial, targeted stretching can also provide relief. Here are some of our recommendations:
- IT Band Stretch: Cross one leg behind the other and lean away from the back leg
- Hip Flexor Stretch: Step into a lunge position, keeping your back leg straight
- Quad Stretch: Pull your heel toward your glutes while standing
- Calf Stretch: Step one foot back and press your heel down
Hold each stretch for 30-45 seconds and repeat 2-3 times per leg.
The Role of Running Insoles and Knee Support
Custom Insoles and Orthotic Support
Enertor Running insoles absorb 51% of impact and can be a valuable tool in your injury prevention toolkit. Tom recommends using Enertor insoles to help reducing the load on your knees: "I think it's a part of a wider toolbox of how might you reduce the stresses and loads on a certain area. I've definitely recommended them to people.
"Similarly to if you want to keep running, you may strengthen your knee by going on an inclined treadmill. If you have plantar fasciitis or lower limb injuries, put your insoles in. Reduce a bit of that load and it might keep you running whilst injured."
Orthotic Insoles for Running
Orthotic insoles for running shoes can help address biomechanical issues that contribute to knee pain. They work by:
- Improving foot alignment
- Reducing excessive pronation
- Absorbing impact and distributing pressure more evenly across the foot
- Reduce impact on feet, knees and hips
- Supporting natural foot mechanics
When to Consider Running Insoles
Custom insoles may be particularly beneficial if you have:
- Flat feet or high arches
- Leg length discrepancies
- Previous injury history
- Persistent knee pain despite addressing other factors
- Or also struggle with back or hip pain whilst running
Enertor insoles are clinically proven to relieve injuries by absorbing 51% of sock, reducing the risk of injury by 66%, and enhancing energy return in order to prevent running fatigue.
Check out the full range of Enertor insoles
Creating a Comprehensive Prevention Strategy
The Practical Approach
Tom emphasises keeping things simple: "From my perspective, I think it's always useful trying to find a couple of not over prescribed exercises. I don't like giving 10 exercises, but a few things that you could maybe just do in your living room whilst you're watching TV or recovering or something really simple that you get a bit more."
Your Action Plan
- Assess your running form: Check your cadence and work on landing under your body
- Build gradually: Increase mileage slowly before adding speed or hills
- Strengthen consistently: Focus on hips, calves, and quads with simple exercises
- Consider your gear: Evaluate your shoes and consider orthotic insoles if needed
- Listen to your body: Address pain early rather than pushing through it
IT Band Syndrome or Runner's Knee: Getting the Right Diagnosis
While the symptoms can overlap, proper diagnosis is important for targeted treatment. Both conditions respond well to similar management strategies focused on addressing load versus capacity imbalances.
If you're experiencing persistent knee pain, consider consulting a physiotherapist who specialises in running injuries. They can help differentiate between IT band syndrome and runner's knee, ensuring you're addressing the right underlying causes.
Conclusion
Preventing knee injuries when running comes down to understanding the balance between load and capacity. By addressing your running technique, building appropriate strength, and using tools like orthotic insoles when needed, you can keep your knees healthy and your running goals on track.
Remember, small changes can make a big difference. Whether it's increasing your cadence by 5-10%, adding a few strengthening exercises to your routine, or investing in proper knee support for running, these incremental improvements compound over time.
The key is consistency and patience. As Tom reminds us, there's no need to overcomplicate things - focus on a few key strategies and implement them consistently for the best results.
This article is based on expert insights from Tom Harrison at PacePhysio, a specialist running and sports physiotherapy clinic. For persistent knee pain or injury concerns, always consult with a qualified healthcare professional.