The key to crushing your fitness goals may come down to something as simple as changing the time you workout.
If you want to run faster and lift heavier, research shows you should hit that snooze button and workout in the afternoon, according to Daniel Pink, author of, “When: The Scientific Secrets of Perfect Timing.”
If you want to lose weight, set your alarm for an early morning workout, according to Pink, who analyzed decades of research for the book.
“There really isn't a perfect time to exercise,” he told "GMA." “It really depends on what you're trying to achieve.”
People who hit the gym for their mental health are better off exercising the morning, noted Pink.
"One of the greatest benefits of morning exercise, at least in my view, is that exercise gives us a mood boost," he said. "We feel better."
Pink added, "That can last a long time and if you exercise in the morning, you get that mood boost and it lasts a big chunk of the day."
On the other hand, if you want to set personal records, working out in the afternoon or early evening can help you reach your peak performance.
"Afternoon exercise seems to be better for performance overall," he said. "Lung performance is higher at that time of day and eye-hand coordination is better that time of day and also speed is better."
Pink attributes that quality to the fact that our bodies are more warmed up by the middle to end of the day.
For that same reason, afternoon and evening exercise is preferred to avoid injury because, according to Pink, "you're literally more warmed up."
If you want to actually enjoy exercise, and not dread it, you can also sleep in and schedule an evening workout instead.
"Late afternoon, early evening exercise, people report enjoying it more at that time of day, particularly, finding it less effortful," Pink said. "I think the reason for that is body temperature."
He continued, "We're more warmed up and so people seem to enjoy it more, and find it less of a strain."
"When" by Pink explains the best time to do anything, from running a marathon to asking for a raise to writing a book.
No matter your goal, Pink found motivation for exercise also comes when you are facing a life milestone, like the end of a decade.
"29-year-olds are twice as likely to run a first marathon as 28-year-olds and 30-year-olds," he said. "Another age at which people are disproportionately likely to run a first marathon is 39 and also 49. It all has to do with endings."
"When we get to the end of something, even something as arbitrary as a life decade, it tends to energize us," Pink explained. "We kick a little bit harder."
Hear more from Daniel Pink on the “10% Happier With Dan Harris” podcast on Apple Podcasts, Spotify, TuneIn, Google Play Music, Stitcher, ABC Radio Podcasts and on the ABC News mobile app under the “Listen” tab.