How Fast is Too Fast?

Greg’s Corner


How fast is too fast?

One of the biggest questions I get during training cycles is: “how fast should I be going on my runs?” Most people are surprised by the answer I give them, because it’s usually, “slower than you are currently.” One of the key pieces of a training plan is consistency, not only with running but with your paces. Make easy days easy and hard days hard.

To start this conversation we want to look at why you should slow your easy days down. The simplest answer is that it keeps your legs more fresh for workout days so you can really get after your goal paces and splits. You want to think about how your body is working during your run. What is your body burning and using for energy?

When your body becomes more aerobic during your easy runs, you teach your body how to use more fat efficiently. The majority of the time on your easy (slow) runs are spent in this aerobic (oxidative) phase. You can stay in this phase for long periods of time vs going anaerobic (no oxygen). The more you train in the aerobic phase, the more efficient your body will be at using oxygen to produce energy. In turn you will be able to run longer and feel more comfortable as you begin to build your base miles.

Your body will also learn to integrate the cardiovascular, respiratory, and muscular systems more effectively. This will allow you to run with less effort on your faster days because all systems will be firing together. When your body is comfortable with this, your runs will depend mainly on slow twitch muscle fibers, which are the ones that work aerobically, allowing you to run longer at a more consistent pace.

Slower runs also help to develop bones, tendons, and ligaments vs faster runs which focus mainly on muscles. These slower runs stress these tissues just enough to actually help them get stronger and lubricate the joints.

So how do you know how slow is slow enough? Well that’s the easy part, all you have to do is be able to have a conversation while you’re running without being super winded. If you find yourself gasping for air, slow down. You can get very scientific and figure out resting heart rate and max heart rate and do some math but we can save that for another post. Take it easy out there and keep your mind open and relaxed. Think about this on your next run when you are asking yourself if you are going fast enough. You are probably going too fast!


Greg Laraia

ATC