Departing Denver Broncos quarterback Peyton Manning’s determination to win Super Bowl 50 against the favored Carolina Panthers was riveting. It reminded me of a quote he gave earlier in his career: “Being there every week for my teammates is really important to me. It’s about accountability.”

That’s discipline, and it’s rooted in little things. Isn’t everything? Little things sow the seeds. The harvest comes when you can discipline yourself to routinely face life’s toughest complications and frustrations. That’s a crystal-clear window on the success of the oldest quarterback in Super Bowl history and the only starting quarterback to win with two different teams.

Denver’s discipline shone in both directions. Wade Phillips, coordinator of the Broncos’ imposing defensive machine, is the son of Bum Phillips — the former head coach of the Houston Oilers and the New Orleans Saints, who always wore a cowboy hat. According to Bum: “The only discipline that lasts is self-discipline.”

Whenever I eyeball the resume of someone applying for a management job, I look for evidence of self-discipline: As candidates have prepared themselves for past jobs, did they identify and master at least three to five key self-disciplines essential to future success?

Did the candidates stick to their routines — even their daily exercise program — after suffering a career setback? Dedicated self-discipliners invariably bounce back the fastest.

Does a prospective manager grasp that the self-disciplines needed by the people around her or him probably differ from the ones that bosses master themselves? Managers shore up their strengths with diverse players, not copycats of the head honcho.

Uncommonly strong self-discipline is a hallmark of success in any era. Elon Musk, who’s worth a comfy $12 billion-plus, tops today’s list for innovative business thinkers. He will turn 45 later this year. After co-founding PayPal, Musk masterminded the product architecture of Tesla Motors, founded SpaceX and provided the initial concept and financial capital for Solar City. Tesla Motors’ battery technology has electrified the industry, if you’ll excuse the figure of speech. SpaceX is redefining space travel with reusable launch components, and may one day colonize Mars.

Management guru Peter Drucker once quipped: “There is nothing so useless as doing efficiently that which should not be done at all.” The relevance? Be careful about those self-disciplines you choose to hammer into habits:

n These days, everyone is hot to develop abs of steel. Fitness training technologies have evolved like every other discipline. It pays to learn them. If you spend valuable time working up a sweat, best practices produce the premier payoff.

Roy Neuberger, who lived to be 107, made several fortunes, and thereby endowed numerous art museums. At 94, he paid a personal trainer $45 three times a week to help him through a 45-minute workout. At a buck a minute, it helped keep Neuberger spry enough to collect his National Medal of the Arts at the White House at age 104.

n You may bust your buttons with pride about how regularly you stay in touch with your network, but are you using the cutting edge of social media to do so? Or are you still sending pals press clippings when everyone else is routing them links?

n I have readers hooked on audiobooks: a great habit to make. If you listen on airplanes, do you also use noise-canceling headphones? A number of physicists and ear doctors point out that these more expensive headsets allow lower-volume playback, and that spares precious hearing.

Be choosy about the number of self-disciplines you adopt. You don’t want to morph into a robot. Focus on doing a few well. And always remember: The only way up is up to you.

Mackay’s Moral: Long-haul winners listen to their built-in drill sergeant all the way to the finish line.

Harvey Mackay is the author of the New York Times best-seller “Swim With the Sharks Without Being Eaten Alive.” He can be reached through his website, www.harveymackay.com, by emailing harvey@mackay.com or by writing him at MackayMitchell Envelope Co., 2100 Elm St. SE, Minneapolis, MN 55414.