By Dr. Mercola

Modern fitness research offers many potent reminders that physical activity is one of the best "preventive drugs" for many common ailments, from psychiatric disorders to heart disease, diabetes and cancer.1,2 

Many studies have also confirmed that prolonged sitting is an independent risk factor for disease and early death. So it's no major surprise to find that inactivity may be costing the global economy tens of billions of dollars each year in lost productivity and healthcare costs.

As reported by Reuters3 and others,4 a recent study5 looking at data from 1 million individuals worldwide found that lack of physical activity had a global price tag of $67.5 billion in 2013. 

Of this amount, $32.2 billion was paid by the public sector, $12.9 billion by the private sector and $9.7 billion by individual households. According to their findings, one hour of daily exercise could eliminate a majority of these expenses.

According to the researchers, inactivity is also the cause of more than 5 million deaths per year. To put that into perspective in terms of being a risk factor, smoking kills about 6 million annually.

Non-Exercise Movement and Exercise Are Equally Important

The World Health Organization (WHO) recommends getting a minimum of 150 minutes of moderate exercise each week, but even this may not be enough, according to the researchers of this study. 

Ulf Ekelund, Ph.D., a senior fitness scientist and professor at the Norwegian School of Sports Sciences and Cambridge University, told Reuters:

"You don't need to do sport or go to the gym … but you do need to do at least one hour a day," he said, giving walking at 5.6 km [3.5 miles] an hour (km/h) or cycling at 16 km/h [10 mph] as examples of what was needed."

I've often stressed that non-exercise movement, such as standing up at work and walking more, is just as important as a regular fitness routine. On the other hand, this research also points out that having a fitness routine is just as important as staying active and avoiding sitting. As noted by Reuters:

"People who sat for eight hours a day but were otherwise active had a lower risk of premature death than people who spent fewer hours sitting but were also less active, suggesting that exercise is particularly important, no matter how many hours a day are spent sitting. 

The greatest risk of premature death was for people who sat for long periods of time and did not exercise, according to the findings …"

In short, you need both. The more time you spend sitting, the more you need to exercise. On the other hand, while sitting less reduces the amount of exercise you need, it does not entirely eliminate your exercise requirement.

But just how much movement and regimented exercise do you need? Previous research has provided valuable clues that are worthy of attention.

How Much Exercise Do You Need?

One impressively large study looking at the exercise habits and health of 661,000 adults revealed there is in fact a "Goldilock's zone" in which exercise creates the greatest benefit for health and longevity.6

As expected, this study confirmed that those who did not exercise at all had the highest risk of premature death. But some of its other findings were more intriguing:7

• Those who exercised but did not meet current exercise recommendations of 150 minutes of moderate exercise per week lowered their risk of early death by 20 percent

• Those who met the guidelines of 150 minutes per week of moderate exercise lowered their risk of death by 31 percent during the 14 year study period, compared to those who did not exercise

• Tripling the recommended amount of exercise had the greatest benefit. Those who engaged in moderate exercise such as walking for 450 minutes per week (7.5 hours a week or a little over an hour a day), lowered their risk of premature death by 39 percent, compared to non-exercisers

• Those who exercised at 10 times above the recommended level only gained the same mortality risk reduction as those who met the guidelines of 150 minutes per week

A second large-scale study8 that focused on exercise intensity found that upping the intensity from time to time also had a definitive impact on health and longevity. Here, health survey data from more than 200,000 adults was pooled.

Spending up to 30 percent of the weekly exercise time doing higher intensity exercises led to a 9 percent lower risk of premature death compared to exercising the same amount of time at a consistently moderate pace.

The greatest benefit was found among those who spent MORE than 30 percent of their exercise time doing high intensity exercises. This group reduced their risk of premature death by an extra 13 percent, compared to those who did an equal amount of low to moderate exercise.

So, to summarize, the data suggests that for optimal health and longevity, you want to exercise for at least 7.5 hours per week (about one hour per day), spending at least 2.25 hours a week (20 minutes a day) doing higher intensity exercises.

How Much Non-Exercise Do You Need?

The other question is how much general activity or non-exercise movement do you need? This question is a bit more difficult to answer but, in general, it appears safe to say that the more the better. Some studies have offered some general clues though.

For example, a recent study published in the American Journal of Preventive Medicine found that sitting for more than three hours a day is responsible for 3.8 percent of all-cause deaths in the 54 countries surveyed.9

Reducing your sitting time to less than three hours a day could increase your life expectancy by 0.2 years, the researchers concluded.

Reducing sitting time by 50 percent (mean sitting time being 4.7 hours a day) would result in a 2.3 percent decline in all-cause mortality. This may not sound like much, but the real value is not necessarily living longer but rather being healthier while still alive. 

Non-Exercise Movement Improves General Health

As explained by Dr. James Levine, who has dedicated a large part of his career to investigating the health effects of sitting, the simple act of standing upright is responsible for activating a number of molecular functions.

Within 90 seconds of standing up, the muscular and cellular systems that process blood sugar, triglycerides and cholesterol — which are mediated by insulin — are activated. 

These molecular effects are activated simply by carrying your bodyweight upon your legs. These cellular mechanisms are also responsible for pushing fuels into your cells. When done regularly, this may radically decrease your risk of diabetes and obesity. Levine's research reveals that, at the molecular level, your body was designed to be vertical and on the move all day long. 

According to Levine, when you stop moving for extended periods of time, such as when you're sitting at your desk working on a computer all day, you're essentially telling your body it's time to shut down; no need to maintain life-supporting functions any longer because your inactivity signals the organism (you) is preparing for death. 

So while you certainly need to sit down and rest now and then, rest is supposed to break up activity, not the other way around. The posture assumed when sitting on a chair or couch also has an adverse metabolic impact. 

Not only is it bad for your back and neck, but it also switches off "the fundamental fueling systems that integrate what's going on in the bloodstream with what goes on in the muscles and in the tissues,"Levine says. For example, sitting causes a rise in your blood sugar levels, blood pressure, cholesterol and toxic buildup, all of which have adverse health consequences over time.

Poor Fitness Is Second Only to Smoking as Risk Factor for Premature Death

In related news, another recent study found that poor aerobic fitness (measured as VO2 max) is second only to smoking as a risk factor for premature death. For this study, more than 790 middle-aged and older men were analyzed, and "each measurable increase in fitness level translated into a 21 percent lower risk of death over 45 years of follow-up," reports.10

Smoking was the most significant risk factor for premature death, but aerobic capacity was actually more potent a factor than high cholesterol and high blood pressure. Dr. William Zoghbi, chief of cardiology at Houston Methodist Hospital in Texas told "The surprising part of the finding is that [physical fitness] is prognostically important so many years down the line. A message we've heard before is that physical fitness is really a major determinant of longevity. This study supports it."

Balanced Variety Is the Key to Optimal Health and Longevity

Even if you're eating the best diet in the world, you still need to stay active and exercise on a regular basis if you seek to optimize your health and longevity. I've often equated exercise to a drug from the perspective that they both need to be taken at optimal dosage to reap the desired effect.

One way of looking at the impact and benefits of non-exercise movement versus exercise is that the former will help optimize your health and quality of life, while the latter may help you live healthy significantly longer. Both are important. 

As for the optimal weekly time investment, remember that the greatest effect on longevity was found among those who engaged in 150 to 450 minutes of exercise per week, the bulk of which was moderate intensity activities such as walking. Including bouts of vigorous activity can give you an additional boost in longevity. As for non-exercise movement, a general recommendation would be to limit your sitting to three hours a day. 

In the final analysis, one of the keys to optimal health is to remain as active as you can, all day long. Whenever you have a chance to move and stretch your body in the course of going about your day, do so.

And, while not highlighted in any of the studies discussed here, your best bet is to incorporate a wide variety of activities, including core-strengthening exercises, strength training, stretching and high-intensity activities. High-intensity interval training (HIIT) boosts human growth hormone (HGH) production, which is essential for optimal health, strength, vigor and yes — longevity.

Originally Posted: Dr. Mercola