To get or stay in shape, the best time to exercise is whenever you can do it consistently. But there also are ideal times to work out that can help you reach more specific goals, such as feeling more productive at work or getting a better night’s sleep.

If you’ve ever scored a coveted pair of shoes at the sale price or cashed in a stock just before the price took a dive, you know the difference good timing can make in your quality of life. So it goes with physical activity.

Of course, your exercise time can depend on everything from your work schedule to when your kids get up or go to bed. But if you have any flexibility in your routine, use targeted times for fitness. These times may vary depending on what you want to accomplish.