It's sometimes easier to keep a morning routine consistent. Afternoon and evening workouts are more likely to conflict with other responsibilities as the day progresses. Plus, a full day’s work can take a serious toll on willpower, which can overcome any gym-goer’s best intentions.
Morning workouts might also be a good option for stress-free snoozing. Since exercise increases heart rate and body temperature, working out too late in the evening (generally after 8 p.m.) may disrupt sleep, while studies show that working out at 7 a.m. (compared to 1 p.m. or 7 p.m.) may help people sleep more soundly at night.
Finally, one study found that 45 minutes of moderate morning exercise (like walking briskly on the treadmill) helped curb appetite directly after working out. Research also shows that people can burn up to 20% more body fat exercising on an empty stomach—much easier to do first thing in the a.m. than at night!