But as it turns out, how hungry you are post workout depends on how intense or how long that workout really was.
A recent study published in Journal of Endocrinology recruited 16 healthy, fit young men (sorry, no women due to controlling for the effects of women’s menstrual cycles). Participants were split into two groups: One group focused on intensity, ranging from an easy jog for 55 minutes (50% of their maximum capacity) to a more vigorous pace for 36 minutes (75% of maximum capacity), until they burned around 600 calories.
The second group focused on length with a run for 45 minutes at a steady pace on one day, followed by a run for 90 minutes at the same pace on another day (70% of maximum capacity). Throughout the experiment, both groups ate standard meals and levels of ghrelin — a hormone thought to influence appetite was measured. Generally speaking, when ghrelin levels rise, so does hunger.