Safely Increasing Your Running Workout Intensity

'Tis the season for stress fractures. With very welcoming weather, the desire to shed winter weight in preparation for the "Beach Bod" increases in just about everyone. Many of us have not been as diligent in our winter workouts as we should, so we start fresh our running routines. Whether we were star athletes back in the day, or are late bloomers who have found our inner athlete, we all feel the temptation to resume our training regimen with enthusiastic gusto. The problem is that--just like at the dessert bar at the local buffet--our eyes are too big for our own good.

Don't let this pic fool you,
I got a stress fracture this day

The danger of training too hard, too quickly is that certain parts of our bodies respond to exercise quickly and are able to adapt and grow, while other parts don't respond nearly as quickly. Muscle, for example, adapts very quickly to working out because it has plenty of blood flow, bringing oxygen and nutrients needed for repair of the small amounts of damage that happen with workouts. Tendon and bone, however, respond much more slowly. Bone has plenty of blood flow, generally speaking, but requires work by two different cell types to repair and rebuild damaged bone. Tendon has very little blood flow, so it takes a long time for nutrients to reach the areas that have been stressed.

These limitations aren't deal-breakers, but they do mean you have to train smarter, not always harder. They require a measure of self control, not merely stamina. Just because your lung capacity can maintain a pace, and your muscles won't give out immediately after starting a run doesn't mean you can train until you feel tired. Your bones and tendons weaken quicker and rebuild slower, so they're the limiting factor in your workout. Compounding the problem is that you often don't feel pain in these body structures until hours or days after they were injured.

The sum total of these factors is that training too hard is very easy to do, tendinitis and stress fractures are common in the spring for exactly these reasons. The best way to avoid this is to train at a rate that these structures can handle while patiently increasing your workload over time. This gives the bones and tendons time to strengthen so you don't run into these setbacks that lead to nagging injuries all running season. Also, I'd recommend making sure you have good running shoes before you start training (if you aren't familiar with the "squish test," go read my earlier post "A Treatise on Heel Pain"). Make sure they're properly broken in before you log significant miles on them.

Last year, I did exactly what I'm telling you not to do

How do we do this? That's a little tricky because it depends on your level of training, your recent history of activity, and your genetic bone/tendon structure. For a new runner, start slow. I hesitate to even give a distance or a pace, because everyone's starting points are so individual. If you've never run more than a hundred yards without stopping before, I'd stay away from a half-mile run--you might start with a few weeks of brisk walking--for example. If you're a seasoned marathoner who is getting over a training injury, you probably have a little more leeway. The important thing is to stop before you feel taxed for the first few weeks. Run at a pace that is very easily sustainable. Usually that means just to the point that you couldn't easily carry on a conversation with a person running next to you.

After going a week or two at this distance and pace, increase one or the other (never both distance and pace at the same time) for another week. Then advance whichever of the two you didn't increase last time. If at any point of your training, you feel pain or weakness, back off. Remember, you can avoid long-term setbacks and maintain your fitness level more effectively if you don't have to stop training to heal.

The key is gradual transition. If you go too fast, you risk injury. If you go too slow, you won't improve, so you do have to increase your workout in order to benefit--just don't do it too quickly. Training injuries happen, even in accomplished professional athletes, but they get paid to be athletes and push their limits. You might not, so be smart and avoid injuries so you can be your best self.