Baseline measurements really depend on what’s most important to the client.
Do THEY really need to know VO2max, lactate threshold, HR response/recovery or even body comp – when all they’re really interested in is how they LOOK?
If appearance is what’s most important, use progress photos.
If there are particular performance markers that “make or break” success in the client’s mind, measure those.
As trainers, it’s easy for us to get caught up in all the “fun” measurements. Don’t take it personal, but clients don’t really care if WE are having a good time. They’re paying for THEIR results.