When you exercise, your heart speeds up to meet your body's energy needs. If you know your target heart rate, you can make sure you're exercising hard enough to get a good workout, but not too hard to strain your heart.

The great benefit of living with, working for, or being related to people who have experienced more of life than you have is picking their brain for advice.

The most effective people learn from their own mistakes, and make a significant effort to learn from other people’s errors as well.

A recent Quora thread asked users for the best advice they’ve ever gotten.

Some people have a way of making the complex clear.  They know who they are, why they do what they do, and where they want to go. Because they have internalized all this, they are able to sharply crystallize ideas and vision. They speak in simple, relatable terms. And they can get a lot accomplished.

According to a new study published in The Journal of Neuroscience, those who recreationally use pot (i.e., smoke once a week) have "significant brain differences" from those with little or no marijuana use.

Dick Grayson is trading his superhero suit for secret-agent cool.

Batman's former sidekick embarks on a new life as an undercover superspy in the comic book Grayson, an action-adventure series premiering July 2 from DC Comics. It's written by Tim Seeley (Revival) and Tom King, a former CIA counterterrorism operations officer.

After a career of being overshadowed by his cape-and-cowled father figure, this is a chance for Grayson "to take off the mask and step out on his own in a world where he's not simply being another hero like the hero he grew up with," King says.

Have you ever had an epiphany? One of those “a-ha” moments where something just clicks for you? Maybe it’s something you’ve been struggling with for a long time, or maybe it was a piece of advice you learned from a friend. Whatever the source of our insight, it’s these moments that bring us to a deeper understanding of our world. The better understanding we have of life, the more we live in the truth.

Below are 33 of the most powerful lessons in my life. I encourage you to share yours with us by leaving a comment below.

“You cannot be really first-rate at your work if your work is all you are.”

The commencement address is a special kind of modern communication art, and its greatest masterpieces tend to either become a book — take, for instance, David Foster Wallace on the meaning of life, Neil Gaiman on the resilience of the creative spirit, Ann Patchett on storytelling and belonging, and Joseph Brodsky on winning the game of life — or have originated from a book, such as Debbie Millman on courage and the creative life. One of the greatest commencement speeches of all time, however, has an unusual story that flies in the face of both traditional trajectories.

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From New Line Cinema, in association with Village Roadshow Pictures, comes the tornado disaster film "Into the Storm." Steven Quale ("Final Destination 5") directs the film, which is produced by Todd Garner ("Zookeeper," "Knight and Day").

Juan Ponce de León spent his life searching for the fountain of youth. I have spent mine searching for the ideal daily routine. But as years of color-coded paper calendars have given way to cloud-based scheduling apps, routine has continued to elude me; each day is a new day, as unpredictable as a ride on a rodeo bull and over seemingly as quickly.

Naturally, I was fascinated by the recent book, Daily Rituals: How Artists Work. Author Mason Curry examines the schedules of 161 painters, writers, and composers, as well as philosophers, scientists, and other exceptional thinkers.

A couple weeks ago I turned 30. Leading up to my birthday I wrote a post on what I learned in my 20s.

But I did something else. I sent an email out to my subscribers (subscribe here) and asked readers age 37 and older what advice they would give their 30-year-old selves. The idea was that I would crowdsource the life experience from my older readership and create another article based on their collective wisdom.

The result was spectacular. I received over 600 responses, many of which were over a page in length. It took me a solid three days to read through them all and I was floored by the quality of insight people sent.

Ultra-powerful, world-speed-record supercars are earning a lot of attention lately. Hot on the heels of Hennessey's 270.49-mph (435.31 km/h) speed record and Koenigsegg's 1-megawatt One:1, we have an all-new contender from a young American start-up. Trion Supercars' Nemesis is an angry, 2,000-hp beast that has its eyes on the world record territory north of 270 mph (435 km/h).

Billionaire Jack Ma shares what type of people you should and shouldn’t work with.

Jack Ma is a Chinese Internet entrepreneur. He is the Executive Chairman of Alibaba Group, a family of highly successful Internet-based businesses. He is also the first mainland Chinese entrepreneur to appear on the cover of Forbes Magazine and ranks as one of the world’s billionaires.