By Dr. Mercola
There are a multitude of reasons to exercise. Just 15 minutes each day can lengthen your life by three years.1 Exercise helps reduce blood pressure, maintain your weight, stabilize your blood sugar and helps fight depression.
The list of benefits to exercise in your life continues to grow each year as researchers make more discoveries about how the human body works, and the integral part exercise plays in your overall health and wellness. Exercise has been a big part of my life for over 45 years, but how I’ve done it has changed.
Unfortunately, while some enjoy sweating, others find the mere thought of exercise to be painful. Researchers recently found a genetically programmed reason you may not enjoy the rewards others do when you exercise.
The good news is you don’t have to exercise for long periods to benefit from the experience and there are strategies you can use to reprogram your brain to enjoy exercise, and reap the short-term and long-term rewards.
Some Get a Mental Boost From Exercise
According to the U.S. Centers for Disease Control and Prevention (CDC), 80 percent of Americans do not get enough exercise each week.2
Survey data from over 450,000 adults found that less than 21 percent of all people meet the recommended amount of exercise — 2.5 hours of moderate-intensity or 1.25 hours of intense exercise per week.
A recent study, led by Rodney Dishman, Ph.D., professor of kinesiology at the University of Georgia, found your genetics may control your drive, pleasure and reward from exercise.3 Specifically, they are the genes that modulate dopamine in your brain.
Dopamine is the reward neurotransmitter in your brain.4 It is released when you experience something that you interpret as being enjoyable.
More of it is released when the experience is not expected, but you’ll still experience a boost in mood or positive feelings even when the event is expected, such as exercising or sharing a special bottle of wine.
Many people experience an increase in the secretion of dopamine with exercise, triggering the reward and pleasure centers in the brain. But, according to Dishman’s research, some people don’t have this experience. Dishman said:5
“Variation in genes for dopamine receptors, as well as some other neural signaling genes, help explain why about 25 percent of the participants drop out of exercise or don’t exercise at the recommended amount.
Combined with personality measures, we think these genes may help explain why some people have a natural urge to be active, while others never do.”
Research Demonstrated Results in Lab Animals and Humans
Researchers initially evaluated lab rats that were selectively bred to be fit and active animals or unfit and inactive. They found differences in dopamine activity between these two cohorts.
This short video describes how dopamine works in your brain. Once researchers discovered the dopamine link, they recruited 3,000 human participants for a clinical trial.
The portion of the study with human participants also accounted for personality and behavior traits that would impact exercise, such as self-regulation, social influences, access to fitness activities, goal-setting and current fitness and skill level. Dishman commented:6
“Our current field trial with humans suggests that variations in genes that encode for dopamine and other neurotransmitters linked with physical activity account for low or high physical activity directly.
These genes also act indirectly, by their associations with people’s acquired motivation to be active and also with select personality traits.”
Dr. Keri Peterson, internist with Lenox Hill Hospital in New York added:
“Dopamine is a chemical in our brains that plays a role in feeling pleasure and regulating drive. The inherited activity of these genes may cause us to seek physical activity or to choose a more sedentary lifestyle.
This preliminary report suggests that the motivation and desire to exercise is hard-wired. You may actually have your parents to blame for being a couch potato.”
It’s Not All Written in Stone
However, while this research finds a genetic link to dopamine activity in the brain with exercise, other research has established that exercise has the ability to change DNA expression and potentially improve your satisfaction and enjoyment with exercise.
In a comparison between the phenotype expression — the physical characteristics expressed by human DNA — of modern man and hunter gatherer societies,7 researchers believe that physical activity is one example of how an environmental factor can impact characteristics expressed by DNA.
The researchers found that years of exercise deficiency could result in an increase in many chronic health conditions in the entire population and not just one individual. Exercise deficiency leads to an increased number of people who suffer from obesity, type 2 diabetes, Alzheimer’s disease, hypertension and osteoporosis.8
Dori Arad, a registered dietitian and certified exercise physiologist at Mount Sinai St. Luke’s Hospital in New York City believes that although some people may be genetically less inclined to enjoy the experience, they can overcome this obstacle. Arad said:9
“Genetics is very, very important, but nothing is written in stone. You can decide to be active and move and do exercise, and in essence you can rewrite your brain so that exercise becomes pleasurable and rewarding.”
Who’s Not Exercising?
In discovering this difference in dopamine activity, scientists have found there may be factors beyond discipline and motivation that drive people to become physically active and enjoy the process. The dopamine connection is one factor, but how you interpret your body reactions to exercise is yet another.
Researchers at Iowa State University have found that your capacity for exercise may be lower than you think. According to Professor Panteleimon Ekkekakis, Ph.D., 50 percent of people who start a new exercise program will stop within the first six months. Although there are many factors that may be responsible, Ekkekakis believes many new to exercise are unable to accurately monitor and regulate the intensity of their program.10
Without experience, overestimating intensity may reduce efficiency of the program and lead to negative affective responses and/or injuries. Both of these factors may increase the dropout rate of people new to exercising. Research from Ekkekakis found the ability to self-regulate during exercise deteriorates as the exercise intensifies to a point that exceeds your body’s ability to exchange gasses.
This ventilatory threshold is also the point at which optimal fitness benefits are developed in people who have practiced a sedentary lifestyle. Without the ability to recognize and regulate exercise intensity, you may push past your limits without realizing it. Essentially, you have a physical capacity beyond which your body is unable to function. This limitation is based on lung capacity, oxygen transport and how quickly oxygen is absorbed and used in muscle tissue.
However, if you try to exercise too quickly or intensely you’ll likely begin to hate the activity and stop. For some people who have been sedentary much of their life, just a short walk after dinner, cooking dinner or doing the dishes may stress your body to your ventilator threshold. The good news is this threshold is not static, but may change with the right exercise.
Rewire Your Brain to Enjoy Exercise
Ekkekakis suggests that for the average person, this ventilator threshold is approximately 50 percent of their maximum ventilation capacity.11 Individuals who are elite athletes may enjoy a threshold as high as 80 percent of their maximum capacity, while those who have lived a sedentary lifestyle may experience a threshold at 35 percent.
There are steps you can take if you’re the type of person who doesn’t enjoy an intense game of tennis, a jog around the park or rowing in the early morning hours, but you understand the impressive health benefits to moving your body each day.
There are two strategies you can use starting today to build a habit that will last a lifetime. The first is to find an activity you really enjoy and then team up with others who provide you with both social interaction during your workout, and reward and motivation to continue the process. Dishman comments:12
“If you haven’t found something which is pleasurable, either the activity or the people you’re doing it with, then you don’t have much reason to continue it. When people start viewing exercise as a duty or obligation, then that’s not a formula for sustained activity. That just puts people in a constant state of dissatisfaction.”
Consider High-Intensity Exercises
I used to be a former sub three-hour marathon runner. Back then, I, along with many people, believed that completing a marathon is the epitome of health. What I didn't know was I was committing a major exercise mistake — one that could have severely damaged my health.
Developing an exercise program to meet your needs means pushing yourself to your current aerobic capacity for short periods of time, and resting between bursts of exercise. This is high-intensity interval training (HIIT), which can be done on an exercise ball, rowing, jogging or other aerobic exercise that meets your current abilities.
You can read more about the benefits in my previous article, “New Research Reveals Why High-Intensity Training Is So Beneficial for Health — It May Even Help Prevent Cancer.” One of the reasons that HIIT works so well for so many people is that you start at your current ability and move forward. If walking increases your heart rate and breathing to your aerobic capacity, you start there. This is not a competition against anyone else except yourself.
Variety Is the Spice of Life
When developing your exercise plan, variety is the name of the game. There are five types of exercises that will turn your fitness routine into a truly comprehensive exercise plan:
• Interval (Anaerobic) Training: This really is aerobic and anaerobic, but the research shows that the anaerobic phase is far more important. The BEST way to condition your heart and burn fat is NOT to jog or walk steadily for an hour. Instead, it’s to alternate short bursts of high-intensity exercise with gentle recovery periods. This type of exercise, known as HIIT, can dramatically improve your cardiovascular fitness and fat-burning capabilities.
Another major benefit of this approach is that it radically decreases the amount of time you spend exercising, while giving you even more benefits. For example, intermittent sprinting produces high levels of chemical compounds called catecholamines, which allow more fat to be burned from under your skin within the exercising muscles.
The resulting increase in fat oxidation increases weight loss. So, short bursts of activity done at a very high intensity can help you reach your optimal weight and level of fitness, in a shorter amount of time. It also promotes the production of human growth hormone (HGH), known as “the fitness hormone,” which can help you add youthful vigor to your years, in addition to promoting weight loss and improved muscle building.
• Aerobic: Jogging, using an elliptical machine and walking fast are all examples of aerobic exercise, which will increase the amount of oxygen in your blood and increase endorphins, which act as natural painkillers. Aerobic exercise also activates your immune system, helps your heart pump blood more efficiently and increases your stamina over time.
Just don’t make the mistake of using aerobics as your primary or only form of exercise, as you’ll miss out on many of the most potent health benefits exercise has to offer.
• Strength Training: Rounding out your exercise program with a one-set strength training routine will ensure that you're really optimizing the possible health benefits of a regular exercise program. You need enough repetitions to exhaust your muscles.
The weight should be heavy enough that this can be done in fewer than 12 repetitions, yet light enough to do a minimum of four repetitions. Avoid exercising the same muscle groups every day. They need at least two days of rest to recover, repair and rebuild.
• Core Exercises: Your body has 29 core muscles located mostly in your back, abdomen and pelvis. This group of muscles provides the foundation for movement throughout your entire body, and strengthening them can help protect and support your back, make your spine and body less prone to injury and help you gain greater balance and stability.
Pilates and yoga are great for strengthening your core muscles, as are specific exercises you can learn from a personal trainer. Even if you aren’t using a personal trainer right now, please watch these sample videos for examples of healthy exercise routines you can do with very little equipment and in virtually any location. Focusing on your breath and mindfulness along with increasing your flexibility is an important element of total fitness.
• Stretching: This is another important piece of the puzzle, and yet overlooked by many in their exercise programs. The right stretches may help heal lower back pain, prevent injuries and improve your ability to move throughout your day. You can read more about stretching and see a sample video in my previous article, “When and How Should You Warm Up, Stretch, Exercise and Cool Down?”