This research demonstrates that the physical properties of shopping carts influence purchasing and spending. Prior research on ergonomics indicates that standard shopping carts, which are pushed via a horizontal handlebar, are likely to activate arm extensor muscles. Prior research on arm muscle activation, in turn, suggests that arm extensor activation may elicit less purchasing than arm flexor activation. The authors thus deduce that standard shopping carts may be suboptimal for stimulating purchases. The authors predicted that shopping carts with parallel handles (i.e., like a wheelbarrow or “walker”) would instead activate the flexor muscles and thus increase purchasing. 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). In a field experiment, parallel-handle shopping carts significantly and substantially increased sales across a broad range of categories, including both vice and virtue products. Finally, in a simulated shopping experiment, parallel handles increased purchasing and spending beyond both horizontal and vertical handles. These results were not attributable to the novelty of the shopping cart itself, participants’ mood, or purely ergonomic factors.

这项研究表明，购物车的物理特性会影响购买和支出。先前对人体工程学的研究表明，通过水平把手推动的标准购物车可能会激活手臂伸肌。反过来，先前对手臂肌肉激活的研究表明，手臂伸肌激活可能比手臂屈肌激活引起更少的购买。作者因此推断标准购物车可能不是刺激购买的最佳选择。作者预测，带有平行把手的购物车（即，像独轮手推车或“助行器”）反而会激活屈肌，从而增加购买量。肌电图 (EMG) 研究表明，水平和垂直手柄都能更强烈地激活上臂（肱三头肌）的伸肌，而平行手柄更强烈地激活屈肌（二头肌）。在现场实验中，平行手柄购物车显着增加了广泛类别的销售额，包括恶习和美德产品。最后，在模拟购物实验中，平行手柄增加了购买和支出，超出了水平和垂直手柄。这些结果不能归因于购物车本身的新颖性、参与者的情绪或纯粹的人体工程学因素。平行处理增加了购买和支出超出水平和垂直处理。这些结果不能归因于购物车本身的新颖性、参与者的情绪或纯粹的人体工程学因素。平行处理增加了购买和支出超出水平和垂直处理。这些结果不能归因于购物车本身的新颖性、参与者的情绪或纯粹的人体工程学因素。