For many people, running is more than just an exercise to stay healthy; it’s a way a life. Countless patients have come into my office desperate for ways to resume running after a low back injury. It’s the “Runner’s High” – that feeling of excitement and satisfaction with running – that continues to drive people back. This is why it can be so frustrating, for runner and doctor alike, seeing low back pain continue to recur with running, forcing many to give it up for good. Don’t be doomed to this fate. Here are some simple facts about how your low back is affected by running and steps you can take to resume running safely.
Fact #1 – Every person will lose 2cm or more of height after 15 minutes of running.
Why? While you run, your spine compresses from the repeated impact of pounding the ground with your feet. The discs (shock absorbers between each bone in your spine) lose height and the small joints in your spine compress. If you have a problem in these areas, running can make it worse.
Fact #2 – On average, if a person runs 1 mile at moderate speed, the spine is exposed to over 200 tons of impact force.
Each time your foot hits the ground while running, the force that travels through your body is approximately 2-3x your body weight. In a 50kg female, for each step, 100-150kg of force is transmitted to your foot, ankle, knee and hip, up to the spine. Over a marathon, 4,000 tons of force will be transmitted to each side of your body! Imagine that same impact on a degenerated or injured spine; easy to see why pain develops.
In many cases, low back pain is not caused by running alone; however, running will force pain to resurface time and time again. During the most acute pain, stop all running. If the pain is moderate-severe, follows trauma or is shooting into your legs, see a physician specializing in spine conditions for evaluation. In most cases, symptoms improve with conservative treatment including physical therapy, medication, bracing, injections, etc. Once the pain has resolved, next comes return to sport. Here are some ideas on how to keep safe while returning to a running program:
- Start the first month with a low impact fitness program (stationary bike or elliptical machine) to regain your cardiovascular fitness level.
- Follow a cross training program initially, mixing running with other forms of aerobic exercise to improve endurance while healing continues.
- Always start on a treadmill: if you develop pain, you can step off and stop immediately. However, if you are in the middle of a 5K run, you now have to walk home in pain.
- Leave 48 hours between your first and second run to see if any pain develops.
- Focus on posture while you run: maintain an upright position with a stable pelvis (imagine the posture of Michael Johnson – US 200M and 400M Olympian)
In addition to these steps, there are three key concepts to keep in mind when getting back to running – surface, shoes and speed.
- Surface – One concept I emphasize to every runner is how important the running surface is to reducing stress on your spine. Ideally, an artificial track is the best surface to run on, bar none. The surface is rubberized, which reduces impact stress. However, finding one in Shanghai is difficult. Therefore, the next best option is a level grass surface or a treadmill, as both have some compressibility to reduce the impact on your body. The worst possible surface is concrete, no compression there.
- Shoes – Having a sturdy pair of running shoes is important to keep your feet and ankles aligned properly, decreasing pain and injury. One misconception is that custom inserts will add cushion and reduce impact force. While inserts help to correct foot or ankle misalignment, no research has shown they do anything to reduce transmitted forces. Some argue that lighter shoes are better; however, research has shown less stability with lighter materials, so there is no advantage in the end.
- Speed – A simple, but key concept: the faster you run, the greater impact to your body. As you increase speed, the ground impact force increases with each step. As well, a longer stride will increase impact forces. For those looking to take all measures of safety, reduce your speed and stride length to decrease body impact force while running.
Remember, the most common reasons people develop pain while running is a rapid increase in intensity, changes in the training program and poor running form. Slowly ease back into a program, focusing on posture while following precautions to protect your spine, and soon you will be on your way back to the natural high of running.