Morning, noon, or night?  When is the best time of day to exercise? Some find that exercising first thing in the morning keeps them energized all day long. These early birds know that getting it out of the way is their best guarantee they'll exercise at all.  Others head to the gym right after work as an extension of their workday. It also provides a nice transition between work and home life.  Still others work out on the night shift; taking advantage of quiet streets and empty gyms. Which group is best off?

Afternoon Athletes

Phyllis Zee, M.D., a neurologist at Northwestern University says late afternoon or early evening is our most productive and beneficial workout time because of circadian rhythms. Circadian rhythms are the body's internal timing mechanism that controls sleep patterns, blood pressure, body temperature, moods and more.  Zee's study says late afternoon provides peak exercise performance because that's when circadian rhythms naturally elevate our body temperature.  Warmer muscles along with smoother pulmonary function, oxygen exchange and blood flow all function better for exercise later in the day. 

Making Time

If you're more concerned with finding any time to exercise than finding your best performance time, many personal trainers say exercise in the morning to make sure you get it done.  Busy days can reroute our best intentions, and skipping the gym may be the only way we can fit in that extra meeting or school event. 

If you can't find one solid chunk of time, break your workouts up.  Several smaller exercise segments may maximize calorie consumption and minimize wear and tear on tender joints and muscles.  Try a 20-minute jog in the morning, a 20-minute walk on your lunch hour, and a set of tennis after dinner.

If your only chance for a workout is nighttime, just go for it.  Some find exercising at night is a perfect stress reliever, while others say the stimulation keeps them awake.  If you have trouble sleeping, try yoga or Pilates, and save the aerobics for earlier in the day.

Personal Best

The best time to exercise depends not only on circadian rhythms but also on your lifestyle, fitness goals, and personal schedule. Pull out that calendar and make the time. Get up early and work out before the kids wake up.  Go biking with the family, or a take a walk with the dogs. If your goal is pumping up your performance, consider that late afternoon time slot.  Weigh the benefits of working with your circadian rhythms against the rhythm of your day.