Since I’ve started running again, I’ve had to re-read my textbooks about the concept of Onset of Blood Lactate Accumulation (OBLA).  Essentially, OBLA is the point at which your body shifts from burning primarily fat to burning primarily carbohydrate.  The significance of this is that when your body has to burn a lot of carbohydrates, it gets overwhelmed and fatigued.  However, if you’re able to keep your body in fat-burning mode, you are able to keep your body from fatigue.  This is because when the body burns fat, it’s a fairly sustainable process.  The body can do it for a long time.  However, whenever the body shifts to burning carbohydrates at a high rate, it eventually builds up a byproduct called lactate.  When your muscles can’t get rid of lactate fast enough, it builds up in the blood and creates fatigue.

OBLA occurs at different levels of exertion for each person.  A sedentary person can typically only get up to about 55% of their maximal exertion before it sets in and starts fatiguing them.  However, a trained athlete can get up to around 85% of their maximal exertion before OBLA sets in.  Obviously, it’s advantageous for any runner to know how to delay their OBLA response in order to maximize their performance.

The cool thing is that the OBLA response can be trained just like anything else in the body.  You train it by overwhelming it, and it responds by becoming more resilient.  Instead of lifting a weight until your muscle becomes fatigued, you run until you become fatigued.  Then, you rest for a little bit and do it again.  This won’t take the place of actual endurance running if you need to run long distances, but it’s a good addition to a running plan.  This is more commonly known as “interval training”.

How to interval train:

1.  Set aside however much time you usually do for your running session
2.  Run quickly so that fatigue sets in sometime between 30 seconds and 5 minutes of running
3.  Rest for however long you ran before you got fatigued
4.  Repeat that cycle until your normal cardio time is over

Notes:  You can do this with any type of aerobic activity (running, cycling, swimming, etc.)  Also, it’s good to change your work and rest periods.  Don’t only run 30 seconds.  Be sure to do other time-periods as well.  The more variation you throw at your body, the better it will respond.  If you’re a long-distance runner, then you’ll probably focus on longer time periods like three to five minutes.  If you’re a short-distance runner, then you should focus on 30 seconds to three minutes.

Good luck!