What is The Best Time of the Day to Run?

The quick and dirty answer to the question is whenever you are more likely to do it.  But the better answer is really depends on what your goal is.  It all starts with your human circadian rhythm.  Basically, your body ebbs and flows with the tides and with that your natural metabolic rate of activity.  Metabolic activity (aka rate of caloric burn) is driven by a lot of things like horomones, diet, fitness, gender, etc but more likely than not you are churning cooler first thing in the morning and peak around 6pm.

 Working out in the Morning

Your body temperature is lower and if you are like most people you’ll probably be low on energy without breakfast.  Your muscles will also require a little extra time to warm up and stretch.  You are more likely to pull something or injure yourself.

 Zen to Fitness (one of my favorite blogs) has an interesting take on working out while fasting

 5 Reasons to Workout fasted

• AM exercise magnifies a positive hormonal response, working out later in the day will enhance cortisol and this is not a good thing before you hit the sack.
• Food releases insulin which blunts fat burning. When you wake Insulin is at its lowest allowing the most fat to be burnt.
• Cardio in the morning wakes you up and gets your body in action for the day, flushing out your lymphatic system and ensuring a flow of energy.
• It will activate your lean and hungry adaptive mechanism which will burn fat and build muscle, especially if you have a fasted weights workout which hits your back and shoulder area (try sprints and pushups).
• Insulin sensitivity is further improved and fasting is prolonged which can have great health benefits, including improved fat loss without disrupting our hormonal balance.

But if working out in the morning is the only time you can actually get it scheduled in because if you are like most people your day gets hectic and it’s easier to find excuses  not to work out…well have a small cup of coffee or tea and don the sneakers.

Working out in the Evening (circa 6pm)

Now this is when you are at the metabolic peak.  You’re running hotter, your circulation is in full swing pumping blood and oxygen to your muscles and more likely than not you’ve got two nutritious meals under your belt to fuel your kick butt workout. 

You’ll burn more calories and you can push yourself harder.  I’ve noticed that some people have no problem working out late at night and falling asleep like a baby.  However working out after 6pm can make falling asleep at night a challenge for most of us.  If you are programmed to eat dinner at 6pm and your stomach is like a European train (always on time), try delaying your hunger signals with a handful of almonds or fruit.