Hi, I cut and pasted this from a web article and I think it probably applies to you. There's also a link regarding why it is good to work out in the morning but I think it really varies from person to person. One of the points you'll find in the link is that PM exercise can affect your sleep but I remember reading that people who are in good shape don't become over stimulated from evening exercise. Consistency is the most important thing!
"Most personal trainers do recommend working out in the morning, but it's not the best option for everyone. Aside from the time constraints imposed on people who work early in the morning, some people are so sluggish that they won't get the workout they'd get at a different time.
I've found that whatever a person will STICK with is his/her best option, in all aspects of fitness. Studies have shown that morning people are usually more energetic and more driven than non-morning people, so they would naturally be more vigilant about exercise. I don't think it's the morning itself that determines this, but a person's tendency to be a morning person.
There are certainly benefits to exercising early in the day, getting your metabolism revved up before you've had any big meals, but you won't burn twice as many calories or anything, and if you're not a morning person, you probably won't enjoy it and therefore won't keep doing it.
If you do exercise later in the day, try to do it at least three hours before you go to bed, so your body can wind down. Otherwise, you might have trouble sleeping, which is totally counterproductive.
Some trainers even take into account the rise and fall of a person's body temperature throughout the day, but I don't think you need to get technical. Whatever fits into your life in a manner that you can comfortably stick with is your best bet!
http://www.weightlossessentials.com/exercise.html
Bobbi
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