See: 3 Qualities That Make High Performers Different From Workaholics

"I'm a recovering workaholic," admits Jullien Gordon, a nationally recognized speaker and founding partner of New Higher, on his website.

Workaholism, he says in a 2014 LinkedIn post, looks similar to high performance on the outside--but they're actually nothing alike.

Gordon spent years doing research and conducting experiments on himself to understand the difference between workaholism and high performance.

He found that while they both look like hard work, "the big difference is how the individual feels on the inside about who they are in [relation] to their work," he explains.

A high performer works hard in "healthy sustainable ways and feels happy and inspired," he adds. Meanwhile, a workaholic "works hard in unhealthy unsustainable ways and feels unhappy and burned out." 

Here are three more subtle differences between workaholics and high performers:

1. High performers know their value. Workaholics allow others to determine their value.

"A high performer knows their self-worth and can thus work with a sense a freedom," Gordon writes. They do periodic self-evaluations of their performance so that they can constantly improve. And, he says, "they create their own feedback loops rather than waiting on feedback from others."

A workaholic, on the other hand, relies on external validation from those around them: bosses, colleagues, and clients. They wait for external evaluations, such as mid-year or annual reviews, to understand how well they are doing, which causes them to work with a constant sense of fear.

2. High performers give 100% at the right time. Workaholics give 110% all of the time.

Gordon says a high performer knows when to "turn it up." They know when they're expected or required to give everything they have--and they save their energy for those occasions.

"They don't buy into the illusion of 110%," he writes in the LinkedIn post. "They know that 110% is unsustainable. Instead they focus on increasing their capacity so that their 100% is better than the competition's 110%."

A workaholic attempts to go all out, all the time. "They have difficulty prioritizing what's important, therefore, everything is important in their mind."

He tells Business Insider: "The hardest worker doesn't always win, but the winner does work harder."

3. High performers do business. Workaholics are busy.

A high performer's primary goal is to do business. "The only thing that matters to them are results," writes Gordon. "If they can't see a way to create value in the moment, they facilitate or strategize instead. They know that like the economy, business comes in waves, therefore they get ready during the dips so they can capitalize during the upswings."

The No. 1 goal of a workaholic is to be busy at all times--as they believe that the busier they are (or appear), the more important they must be.

"Workaholics fill any space in time with busy work because they feel insecure doing nothing," he explains on LinkedIn. "The insecurity comes from not knowing their value."