Per a study published in Psychology of Sport & Exercise:
Even women who prioritize improving their appearance prefer exercise classes where the instructor emphasizes health benefits (“Let’s get fit and healthy”) over appearance benefits (“Let’s get taut and toned!!”).
In the study, instructors who emphasized health benefits wore a loose t-shirt and shorts. Those emphasizing appearance benefits wore traditional snug gym wear.
Surprisingly, while other studies have shown that workout rooms containing mirrors increase exerciser anxiety, mirrors didn’t matter if the instructor’s leadership emphasized health benefits first and foremost.
Bottom-line, if your clients tend to worry about appearance, focus on health instead.