I did some cursory research on this intriguing question, and the answers tended to fall into the: both are important (not so helpful eh?), so you need to consider the various pros and cons of each category OR sleep is more important, when push comes to shove column.
For example, sleep expert/physician Dr. Robert Rosenberg, states:
"Lack of exercise can certainly result in obesity and cardiovascular disease; however, chronic sleep deprivation can lead to problems such as heart disease, cerebrovascular disease, obesity and diabetes. When we get insufficient sleep, our body releases inflammatory mediators such as c-reactive protein, as well as excessive cortisol and adrenaline. We need sleep to clean out the toxins that build up in our brains during the day, such as beta-amyloid and TAU protein, the building blocks of Alzheimer's disease."
Unlucky for me, when it comes to scheduling in exercise, I am usually somewhat tired - especially by Friday after a busy work week - even when I get seven or more hours of sleep. I also have sleep apnea (yes I use the machine) I'm 58 (meaning energy is more limited than when I was 48, 38, etc), deal with some chronic pain (mostly due to arthritis in many joints and post-exercise soreness) and I'm overweight. Also, I have some medical issues that contribute to my fatigue.
Bottom line for me is that I need to find a way to incorporate healthy levels of both into my routine, by honoring my energy needs and the limits of time. As usual! I have already figured out that a routine of playing pickleball, three times a week, for 90-120 minutes each, is the max I can handle right now.
I'm finding with my business demanding so much of me from Monday to Thursdays, the middle of the week play, on Wednesday evenings, is something I have energy to do, however, the other two workouts - on Mondays and Fridays or Saturdays - is like dragging butt.
So I will continue to figure this one out. I like so many find that life is continually changing and I must change with it.
Above all, I'm somewhat open to new ideas but mostly listening to my body. I know I'll get there.
How about you? Are you getting good sleep and good exercise each week?