KEY POINTS

  • Pushing shopping carts with horizontal handlebars activates triceps
  • This has been linked to the act of pushing away things we don't like
  • Using carts with handles that are similar to a wheelbarrow's activates biceps
  • This has been associated with pulling things we like closer to us

The type of shopping cart can affect people's spending, and it has a lot to do with the muscles we activate when we push carts, researchers have found.

Earlier research discovered that standard shopping carts with horizontal handlebars "likely" activate the extensor muscles in the upper arms (triceps), the researchers of a study, published in the Journal of Marketing, said.

In psychology research, the activation of the triceps has been associated with rejecting the things we don't like, just like when we push something away, City University London noted in a news release. On the other hand, the activation of the biceps has been associated with the things we like, such as when people pull things closer to them.

"The authors thus deduce that standard shopping carts may be suboptimal for stimulating purchases," the researchers wrote. 

For their study, researchers had a closer look at standard shopping carts with horizontal handles and the newly designed ones that have parallel handles, much like the ones in wheelbarrows or walkers. The researchers surmised that the new shopping carts with parallel handles would actually activate the biceps, thereby possibly increasing purchases.

A photo of the difference between the standard and parallel shopping carts can be seen here.

"An electromyography (EMG) study revealed that both horizontal and vertical handles more strongly activate the extensor muscles of the upper arm (triceps), whereas parallel handles more strongly activate the flexor muscles (biceps)," the researchers wrote.

Sure enough, a field test revealed that using the parallel shopping carts "significantly and substantially increased sales across a broad range of categories," with those who used the shopping carts with parallel handles spending 25% more than those who used the standard carts.

"These results were not attributable to the novelty of the shopping cart itself, participants' mood, or purely ergonomic factors," the researchers clarified.

Simply put, using the parallel carts may lead to more spending for the consumers and greater profits for the stores, while using the standard horizontal handles may help consumers exercise more restraint on their spending.

According to the university, in the interviews with shopping cart manufacturers, they were surprised to find how the type of shopping carts' handles can impact sales.

"It is shocking to find that making a small change to the position of handles can have such a large impact on shoppers' spending. Indeed, the handles literally cause us to flex our shopping muscles," one of the study's authors, Professor Zachary Estes of Bayes Business School, said in the news release.

"Conversely, the results of this study may be very useful for consumers, with Christmas just around the corner," Estes added. "If shoppers want to minimize their shopping trips and buy their gifts in one go, they can flex their biceps to pull things into their cart. If they wish to minimize spending, standard shopping carts may act as a welcome and unexpected restraint to keep unnecessary purchases out of the cart."

Shopping Cart Representative image. Photo: Pixabay