Filmmaker and runner Alexi Pappas's big dream was to compete in the Olympics. Your dream might be worldwide business success or just to run the most beloved little coffee shop in your hometown. But whatever vision you're chasing, a lesson Pappas once learned from her coach can help you get there. 

How hard should you push yourself when chasing big dreams?

Running might seem far removed from entrepreneurship, but actually tons of founders,  executives, and even researchers insist that running can teach essential lessons in overcoming hardship, sticking with big goals, and mental toughness. So when I came across a piece in blog The Cut interviewing three top international female runners about their life advice for the rest of us, I thought it was worth a look. 

The whole conversation turned out to be fascinating, touching on subjects from the extra challenges faced by Black distance runners to learning from failure, but one bit of advice from Pappas stuck out as particularly relevant for entrepreneurs. 

When asked by The Cut's Bindu Bansinath, "What advice would you give to non-runners when they're attempting something that seems impossible?" Pappas replied that something one of her running coaches once told her sticks with her. 

"He pulled me aside and told me about the rule of thirds: Whenever you're chasing a big dream, you're supposed to feel good a third of the time, okay a third of the time, and crappy or not great a third of the time, and if you feel roughly in those ratios, it means you are in fact chasing a dream. If you feel too good all the time, you're not pushing yourself enough, and if you feel too fatigued, you might be burning out or having a mental-health challenge and need to reevaluate," she explains. 

This idea isn't original to Pappas or her coach--I've seen business leaders reference is before -- but it's a simple rule that packs a lot of wisdom into an easy-to-remember package. Maximizing your potential, learning experts tell us, is all about pushing past your comfort zone. If you're not outside your comfort zone, you're probably not learning very much. 

On the other hand, pushing yourself too hard can result in burnout and injuries, both physical and psychological. We all know this. The trouble is finding the right balance. The rule of thirds takes this generic truth and makes it actionable. To maximize your progress towards difficult goals, you should be well outside your comfort zone (aka feeling lousy) a third of the time. Much more than that is risky. Much less is lazy. 

Resilience in rule form

The rule is useful is for looking back over your progress and assessing whether you should push yourself more or less. But it's also useful in reminding yourself in moments of pain that unpleasantness is an essential part of the process. If you feel terrible sometimes (actually a third of the time) that's not a sign you're not good enough or you're doing something wrong or you should give up. It just means you're trying to do something ambitious. When you understand that truth you're less likely to give up when things get uncomfortable. 

So remember this rule next time you're struggling through a particularly rough patch on the way to your big dream (and maybe this rule too). If you're not feeling this way much more or much less than a third of the time, then maybe you should be encouraged rather than discouraged. 

Interested in more wisdom from Pappas? She spoke candidly to The New York Times about her mental health struggles awhile back and her experience was featured in the fascinating short film below. Check it out for more on her path to the Olympics, what happened after she reached her goal, and why so many high achievers in all fields experience mental health crises.