Agreed. It’s really hard to draw meaningful conclusions from the available information.

You should have at least shown how you controlled or measured confounding variables. E.g. same time of day, same music selection and volume, same room temperature and circulation, same food and drink, same amount of sleep, same clothing, similar or identical athlete weight (important), etc, etc.

Hmmm maybe I should post a thread on how I analyze the HR data I get from my ergometer workouts…. sigh