Human behavior is anything but simple, and for that exact reason I believe that oversimplifications can be useful in the first step of designing for behavior change. When it comes down to it, there’s a lot of human behavior that we can explain in terms of two simple forces: Friction and Fuel.

There’s a metaphor that Dan Ariely uses that I think is very nice, and that’s of a rocket ship. It would work just as well with a plane or a car, but let’s face it — you can’t beat a rocket on the cool-meter. For a rocket ship to fly through space, it needs to not only bypass atmospheric friction and avoid debris, but also consume fuel to propel itself up and out of the atmosphere. Too much friction, and it won’t fly. Not enough fuel, and it won’t fly either.

Too much friction, and it won’t fly. Not enough fuel, and it won’t fly either.

Ok, you get the metaphor. How do these two forces, friction and fuel, play out in healthcare?

Friction in Healthcare

In healthcare, frictions are anything that get in the way of performing that positive health behavior, from the feeling of exhaustion that always arrives when it’s time to exercise to that application form you have to fill out to opt in to your health savings account. Technology can go a long way to decrease friction, removing steps like filling out forms by hand and mailing them, or bringing the doctor to you through your smartphone instead of having to make an appointment, take off time from work, and get to the clinic.

If we return to the rocketship example, we can think about gravity as an important type of friction. The gravity of our lives — the thing that is always there and keeping us steady and stable — that’s the status quo. We can move against the status quo, but it takes some effort. Just like gravity, the status quo may be an invisible force, but it’s deceivingly powerful. One way to combat the status quo is to add fuel.

Fuel in Healthcare

Fuel is anything that makes a positive health behavior more appealing, from the gamification of un-fun procedures to delivering incentives (rewards, discounts, and so on) contingent on good behavior (like the WellnessWins rewards program from WeightWatchers). Fuel doesn’t have to come in the form of tangible rewards like baseball hats and travel shoe bags, and in fact the joy of playing a game can be even more motivating than winning a prize. For example, one study (Kumar, Wentzell, Mikkelsen, Pentland & Laffel, 2004) used a guessing game to incentivize diabetic children to better manage their condition (“try and predict your next blood glucose measurement!”).

Personally, there’s nothing that gets me moving like a good old-fashioned competition. But if competition is not your thing, try temptation bundling (Milkman, Minson & Volpp, 2013) where you pair “want” activities (like listening to an addictive audiobook) with “should” activities (like exercise). If you only allow yourself to consume The Hunger Games while on the treadmill, you’ll be much more likely to get to the gym.

These are just a few examples of friction and fuel in healthcare, but we’ve added a lot more to the comprehensive Friction and Fuel Framework, which we’ll share with you if you trudge through a bit of friction and share your email address with us (don’t worry, we promise not to do anything evil with it).

Behavioral science is incredibly complex, but the reality is that it’s possible to use these two simple concepts of friction and fuel to make a big difference in behavior change. You can decrease friction and add fuel to make desired behaviors simple, salient, and appealing — and, importantly, more likely to actually happen.

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  1. Kumar, V. S., Wentzell, K. J., Mikkelsen, T., Pentland, A., & Laffel, L. M. (2004). The DAILY (Daily Automated Intensive Log for Youth) trial: a wireless, portable system to improve adherence and glycemic control in youth with diabetes. Diabetes technology & therapeutics, 6(4), 445-453.

  2. Milkman, K. L., Minson, J. A., & Volpp, K. G. (2013). Holding the Hunger Games hostage at the gym: An evaluation of temptation bundling. Management science, 60(2), 283-299.

Written by: Aline Holzwarth