If you still prefer workouts later in the day, they can have their own unique benefits, too. Evening exercise — between 6:30 p.m. and 8:30 p.m. — “greatly” increased upper body muscle strength, power and endurance, and enhanced overall mood for women, according to the study published in Frontiers in Physiology.

For your heart health, ACSM guidelines recommend 150 minutes of moderate-intensity aerobic physical activity each week. In a given week, that works out to 30 minutes of moderate exercise five days per week. Or if you're looking to do more with less time, ramp up the dial.

As a general goal, aim for at least 30 minutes of moderate physical activity every day. If you want to lose weight, keep off lost weight or meet specific fitness goals, you may need to exercise more. Cutting down on sitting time is important, too.

According to their research, funded by the National Institutes of Health, the optimal length of exercise per week is: minimum of 5 to 10 hours of moderate physical activity (42 minutes to an hour and 25 minutes daily) minimum 2 hours and 30 minutes to 5 hours of vigorous physical activity (21-42 minutes daily)