Is it better to work out in the morning or evening?It’s a question I’ve been asked a dozen times.My go-to reply is generally, “The best time to work out is the time you can work out.” Because really, we’re all pretty busy, and finding any time is a check in the positive column.That said, if you’re shooting for peak performance and don’t have time constraints, p.m. has a slight edge over a.m. Those evening hours may help you hit a personal best, according to a study published in PLoS One.The reason appears to lie in the natural fluctuation of our hormones and metabolism from morning to night.When Brazilian researchers had a group of cyclists perform a series of 1,000-meter time trials at either 8 a.m. or 6 p.m., the riders’ glucose levels were 11 percent lower in the morning. They also had higher levels of the stress hormone cortisol and other chemicals that are counterproductive for performance.The result: The cyclists produced more power in the evening and finished the time trials 6.5 seconds (or 7 percent) faster.Now if you’re shooting for weight loss, go ahead and rise and ride.Unless you’re doing a long and/or hard ride, you don’t even have to eat first. A study published in the British Journal of Nutrition found that folks who did a moderate workout before breakfast not only burned 20 percent more fat, but were also less hungry later in the day than those who ate their morning meal first.So each time of day has its benefits. Just make sure you get out and ride. If you need pointers on how to fit cycling into your busy schedule, check out our tips for making time to ride.