Believe it or not, some of the technologies that NASA develops share common exercise, process, and physiological goals with football teams. But that’s not what I’m going to talk about today. Instead, I’m going to share a simple and easy to implement NASA-developed survey that could help football coaches assess the mental workload that their players experience during practice.

You may be wondering why this would be useful so let me briefly explain. If a person experiences cognitive overload during a physical task, such as during practice, then their performance is likely to degrade, as is their ability to learn…

Most people would agree that a highly engaged athlete off the field will have a greater chance at being a better player on the field. But what does it really mean to be engaged and as a coach, how can you design environments that encourage it?

For the purposes of this post, and in the specific context of athletics, I operationally define engagement as the active state of seeking out a challenge where challenge is operationally defined as cognitive load. Note that engagement does not refer to physical challenges, but instead it relates to one’s mental state.

In other words…

Suppose you and I met up for lunch, and at the last minute you decided to bring a friend along. Unbeknownst to you, I had actually asked you to lunch because I was in a generous mood and wanted to give you $100. I felt bad that your friend might feel left out so I gave her the rest of the money in my wallet which was only $50. After lunch we decided to walk over to a coffee shop. It was turning out to be a great day!

Unfortunately, along the way, you lost one of the 50 dollar…

Sitting in a utilitarian beige room on those uncomfortable chairs that are often found in government offices, a committee of eleven civil servants sat hunched over copies of a large, seemingly never-ending 400-page document. The first topic up for discussion is a proposal for the construction of a 90 billion dollar nuclear power plant.

The chair of the committee has just completed an extremely thorough and lucid argument outlining the pros and cons for the current design, and now it is the job of the committee to deliberate and vote on the proposal. As you may have guessed, a nuclear…

One lovely Saturday afternoon in a San Francisco park, two six-year-olds sat behind a lemonade stand with a sign that read:

Spend a little time, and enjoy C & D’s lemonade

One by one, as people approached to purchase a refreshing glass of lemonade, they were given the option to pay anywhere between one dollar and three dollars for their beverages. The choice was completely theirs. After ten minutes went by, the sign was replaced with another sign that read:

Spend a little money, and enjoy C & D’s lemonade

And again, as people stopped by for a delicious summer…

Doherty’s Threshold

When a computer and its users interact at a pace that ensures that neither has to wait on the other, productivity soars.

Human Factors Perspective

Imagine you finally found the perfect gift for a friend after spending hours scouring Website after Website. It’s a little expensive but you know she will absolutely love it so it’s worth the extra cost. You quickly add the item to your cart and enter your credit card information. All you have to do now is click on the “Confirm Purchase” button. You promptly do so, and that’s when it all begins to fall apart.

You first sit…

Any task will inflate until all of the available time is spent.

Parkinson’s Law

Work expands so as to fill the time available for its completion

In 1955, Cyril Northcote Parkinson, a British naval historian, wrote a pithy article for the Economist where he detailed his observations of the seemingly ever-expanding bureaucratic tendency to hire more people to do the same amount of work. He observed that, if given the chance, people tend to use as much space, time, or budget as they have been allocated, regardless of whether or not those resources were fully required.

Human Factors Perspective

Though originally an observation on how people tend to create needless work for each other, Parkinson’s Law has…

The Law of the Conservation of Complexity

The Law of the Conservation of Complexity (otherwise known as Tesler’s Law) states that every application has an inherent amount of irreducible complexity.

Human Factors Perspective

In the mid 1980s, whilst working at Xerox PARC, a computer scientist named Larry Tesler observed that there is a degree of complexity in every application that cannot be further reduced. In other words every product contains a certain amount of inherent complexity that, if removed, would destroy the value or intended utility of the product.

Tesler proposed that one of the most important questions for designers to answer is “who must deal with the complexity?” Should…


This is the first part of a series on the human factors of teams. I come from a background in psychology, specifically Human Factors (HF) and applied Cognition where we focus on understanding and improving human-technology interaction. In this series, I thought it would be fun and useful to re-purpose many of our laws, principles, and rules for leaders within the domain of human-human interaction.

In my work at Horizon Performance, I focus on designing and assessing high performance products for elite teams such as the Navy SEALs, Army Green Berets, and Division I football teams. …

It’s midway through January and that means in less then half a month 80% of the people who set New Year’s goals will have given up. Sadly, it’s not just a New Year’s phenomenon. Most people find it difficult to achieve the long-term goals they set for themselves regardless of the time of the year. The good news is that there are a few things you can do to ensure a more favorable outcome when it comes to following through with your goals.

In the 1970s a chap by the name of Mihalyi Csikszentmihalyi (pronunciation here) observed several situations where…

David Sharek

I uncomplicate things. Director of UX, PhD in Human Factors and Applied Cognition.

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