HEBS (Homework, Exercise, Breakfast, Sleep)

There is a general sense in the software engineering community that a 10x difference exists in programmer productivity (here is a good summary of the research).

You might (erroneously) conclude from this 10x difference that “some people are born fast at software development, and some people are just born slow”, and assume that your own speed of programming is somehow innate and unchangeable.

I emphatically disagree: while I do believe that some people are innately good at programming, I don’t believe that your “native” abilities completely determine your performance in this class.  Instead,  I believe that your performance during any given WOD will be significantly influenced by four factors:

  1. Homework.  Are you prepared for WOD by having done the homework (i.e. practice WODs) successfully?  As this article summarizes,  practice really does make perfect.
  2. Exercise.   Have you exercised before this WOD? If you don’t think that matters, read this summary of research on the positive impact of exercise on cognitive performance.
  3. Breakfast.  Mom always said breakfast is the most important meal of the day.   When your WOD is at 10:30 in the morning, breakfast is clearly relevant. As you might guess, research also suggests a link between breakfast and cognitive performance.
  4. Sleep.  Yes, you need sleep, and if you’re not getting at least 8 hours consistently, you’re probably not going to finish the WOD as quickly. Read this article for a summary of the findings.

OK, so how do you investigate the impact of these factors on your own productivity?   I am going to give you a simple approach to help you gain insight, called the “HEBS Scale”.   Before each WOD, you will give yourself a score for each of the four factors on a scale of zero to two as follows:


  • 2 points: if you did all of the practice WODs and repeated them as necessary until you achieved Av performance;
  • 1 point: if you did at least some of the practice WODs, but did not get all of them to Av.
  • 0 points: if you did not do the practice WODs.


  • 2 points: if you did vigorous exercise (surfing, swimming, jogging, etc.) for at least 30 minutes in the 24 hours prior to this WOD;
  • 1 point: if you did mild exercise (walking) for at least 30 minutes in the 24 hours prior to this WOD;
  • 0 points: if you did not exercise in the 24 hours prior to this WOD.


  • 2 points: If you ate a well balanced breakfast (fruit, protein, fiber) today;
  • 1 point: If you ate an “unbalanced” breakfast today;
  • 0 points: If you skipped breakfast today;


  • 2 points: If you got 8+ hours sleep last night.
  • 1 point: If you got 6-8 hours sleep last night.
  • 0 points: if you got less than 6 hours of sleep last night.

On the index card where you record your WOD results, you will now provide a “HEBS” score to help you understand how each of these factors might impact on your WOD performance.

For example, a HEBS Score of “2100” means: (1) you prepared well and achieved Av on all the practice WODs for this module; (2) you exercised mildly during the past 24 hours; (3) you skipped breakfast, and (4) you got less than six hours sleep before the WOD.  Let’s say you DNF’d on that WOD.

Let’s say that on the next WOD, you recorded a HEBS score of “2102”, and this time you got Av performance.  Since the only score that changed was sleep, you might want to start focusing more on your sleep habits and see if this relationship continues.  As you get more and more HEBS scores, you will hopefully start to get a clearer picture of what affects your personal performance.

Another way to look at HEBS scores is by simply summing them up.  Your HEBS score can range from 0 (0000) to 8 (2222).  Perhaps you do well on your WODs as long as your cumulative HEBS score is always 6 or greater.  Collect the data and find out for yourself.

Your HEBS score is not part of your grade for the class (though your ability to complete the WOD is).  My hope is that over the course of the semester, you will start to notice relationships between how you did on a WOD and one (or more) HEBS factors, and that this knowledge will help you to improve your grade.   I am also hoping that at least some of you try to achieve a HEBS score of 2222 on the day of your WODs, and I certainly hope that this results in Rx performance!

Finally, don’t feel the need to restrict the use of HEBS to just software engineering.  Perhaps you’ll find it useful in other areas of your life where performance matters.