Rethinking Workout Intensity

The challenge

iFIT members struggled to determine which workouts were right for them. Existing research showed that the Intensity Scale was confusing, but it didn't explain why. Previous surveys measured attitudes without exploring how members interpreted the concept itself, leaving open the possibility that users and product teams were operating with entirely different definitions of "intensity."

Approach

I led a series of moderated interviews using card sort activities and concept testing to explore how members defined workout intensity, grouped related concepts, and evaluated a proposed classification system. Participants represented a range of fitness modalities and experience levels, allowing us to compare mental models across different types of users.

Key insights

• Members consistently described workouts along two separate dimensions: the skill or experience required to complete a workout ("Level") and the amount of physical effort it demanded ("Intensity"). A single numeric scale failed to capture that distinction.
• Labels carried emotional weight. A newly proposed "Elite" category was viewed as intimidating and exclusionary, suggesting an unattainable standard rather than a useful way to classify workouts.
• Participants naturally used descriptive language like 'easy, moderate, hard' or 'beginner, intermediate, expert' to explain expectations, revealing that meaningful context was more valuable than abstract numerical ratings.

Impact

The research directly informed the removal of the 1-7 Intensity Score and shaped future workout categorization decisions. More broadly, it demonstrated that effective labeling should reflect how people naturally think about a problem rather than forcing them to adopt an internal framework.