Performing accurate weightlifting forms is often hard for novices who have just started this type of exercise, and even experienced gym-goers have reported acute or chronic injuries due to performing incorrect weightlifting forms. Moreover, achieving the fitness goals are more than precise work-out forms and healthy diet. It's a process of behavior change, only continuous work-out could help the users to reach their fitness goals.  

Wearable devices have been designed to help with instructing users on proper exercise forms and keeping track of daily health conditions. Some specific wearable devices are designed to correct weightlifting forms with sets of plans generated by devices based on users' physical figurations, gender, age, and personal information.  

However, those devices simply focus on users' ultimate goals other than their usage of the devices. Different users might have different demands of using those devices. For example, new gym-goers might have less knowledge about weight-lifting forms or any other exercise knowledge, they mainly use the device to learn exercise knowledge such as new forms and appropriate diet with the combination of correcting function. While experienced gym goers primarily utilize the devices for correcting and monitoring their forms to keep them on a good track. However, most of the devices draw attention on generating work-out plans and helping with a healthy diet, few of them focus on how to help users, especially novices, to learn proper forms and continuously motivated users committing to exercise and eventually reach their goals.  

In this paper, we interviewed 7 experienced gym-goers and 7 novices to learn about their needs and expectations from wearable fitness devices. We introduced them to existing wearable fitness tools and brainstormed with them to identify ideal features and concerns for these types of devices.  

To understand these findings, we re-analyzed our data through the lens of Bandura’s principles of self-efficacy, which include enactive mastery experiences, vicarious experiences, verbal persuasion, and physiological and affective states. While prior work has studied self-efficacy as one component of behavior change, our work focuses explicitly on how these four principles can guide design of wearable devices for holistic fitness across different levels of expertise. 

In this work, we differentiate between the needs and practices of people with different levels of expertise in weightlifting, and the impact their expertise had on their experiences of self-efficacy. These findings may have broader implications for the design and study of technologies for behavior change, especially in settings where users encounter challenges that vary over time.