Would that be a correlation study?
I think you have the variables right, and yes I think that would be a correleation study. You are trying to show the level of anxiety as a function of the amount of physical exercise. My own experience is that exhausted people are too tired to be very filled with anxiety. It’s the idlers who become frenetic with fear, neurosis, angst, and mal du spleen, and malaisse. Hearts to God, hands to work is what my local Mennonite neighbors say. I’ve never seen an idle one, or one filled with anxiety. You babycakes are another story. Maybe you should get to the gym more, or swim, or do aerobics, or fencing, or judo. You don’t want to wind up like David Bowie, or Pee Wee Herman, right? I think a better study would be the effect of intense orgasms on anxiety levels. You could get the benefits of low anxiety without a lot of sweaty workouts — maybe with some sweaty smelly messy (if you do it right) sex instead. Correlate that!