Evening exercise = huge cortisol increase (3-4X). But it’s...
Andrew D. Huberman, Ph.D.@hubermanlab
52 views
May 05, 2025
~1 min read
Advertisement
1
Evening exercise = huge cortisol increase (3-4X). But it’s transient. It also leads to much lower next morning cortisol. If you exercise in the evening, bright light viewing (to increase am cortisol) the next morning is extra key b/c am cortisol = elevated focus/energy all day.
2
Takeaway: view morning, bright light, ideally from sunlight. Also, it’s fine to exercise later in the day - that big cortisol surge subsides within a few hours after , although you should avoid pre workout caffeine after 2-4 PM if you want to sleep as well as you could.
3
Keep in mind that part of the reason the evening exercise creates such a big increase in cortisol is that it’s relative to baseline and your baseline cortisol (ideally) is low in the evening. When experimenters have placed a moderate intensity exercise session on top of that low baseline, it creates a huge increase relative to baseline. And when it comes to cortisol, it’s not just the absolute value. Circadian timing matters.
