By Dr. Joseph Mercola | mercola.com
STORY AT-A-GLANCE
- In the most comprehensive study to date of the molecular changes that occur in your body due to exercise, “an orchestrated choreography of biological processes” are demonstrated to occur
- One exercise session lasting eight to 12 minutes leads to changes in remarkable 9,815 molecules in your blood
- Changes are documented related to energy metabolism, oxidative stress, inflammation, tissue repair, and growth factor response
- In the first two minutes after exercise, molecular markers of inflammation, tissue healing and oxidative stress, which is a byproduct of metabolism, rose sharply
- A strong correlation was found among a set of molecules and an individual’s aerobic fitness level, leading the researchers to suggest it may be possible to use a blood test to monitor fitness level
Exercise does far more for your body than simply raising your heart rate and causing you to break a sweat. Physical activity leads to a system-wide molecular response in your body, including changes in inflammatory markers and metabolic pathways.
This gives a glimpse into why the very straightforward act of getting moving is associated with so many benefits to your physical and mental health, from boosting your immune system to protecting cognitive function.
In short, your body is made for exercise and it thrives on it. If there were still any doubt as to its importance, researchers with Stanford University revealed that one exercise session leads to changes in remarkable 9,815 molecules in your blood.1
‘Omics' Reveals Impressive Molecular Choreography of Exercise
The term “omics” is used in the field of biological sciences to describe the study of large sets of biological molecules.2 Proteomics, for instance, refers to the study of proteins within a cell, while metabolomics refers to molecules in the blood that influence metabolism and genomics delves into molecules related to gene expression.3
While previous omics studies have looked into how exercise affects specific areas, such as metabolomics, the featured study, published in Cell, took it a step further.
“We performed longitudinal multi-omic profiling of plasma and peripheral blood mononuclear cells including metabolome, lipidome, immunome, proteome and transcriptome from 36 well-characterized volunteers, before and after a controlled bout of symptom-limited exercise,” the researchers stated.4
In other words, in what is the most comprehensive study to date of the molecular changes that occur in your body due to exercise, providing an unprecedented glimpse into the details of the body's physiological response, it's demonstrated that “an orchestrated choreography of biological processes” occur, including those relating to:5
- Energy metabolism
- Oxidative stress
- Inflammation
- Tissue repair
- Growth factor response
The study involved 36 subjects between the ages of 40 and 75, with a mix of fitness levels and health, including some who were insulin resistant. The volunteers completed a treadmill endurance test lasting about eight to 12 minutes, with blood draws occurring before and two minutes after the session, along with 15, 30 and 60 minutes later.6
Blood draws also took place before and after a period of rest, which acted as the control. “Everybody knows exercise is good for you, but we really don't know what drives that at a molecular level,” Michael Snyder, Ph.D., professor, and chair of genetics at Stanford University, said in a news release. “Our goal at the outset was to conduct a highly comprehensive analysis of what's happening in the body just after exercising.”7
In all, 17,662 molecules were measured, 9,815 of which changed in response to exercise, with some going up and others going down. Certain molecules also spiked immediately after exercise then quickly dropped, while others remained heightened for an hour. “It was like a symphony,” Snyder told The New York Times. “First you have the brass section coming in, then the strings, then all the sections joining in.”8
Molecular Changes Varied by Timing, Health Status
One intriguing finding was how different the metabolic changes were in individuals depending on their health status, particularly relating to insulin resistance, which plays a role in virtually all chronic diseases. In those with insulin resistance, a reduced inflammatory response was noted, and there was a dampened immune response after exercise.
Significant differences were also noted depending on when the blood was drawn, with the researchers describing an “intense flurry of molecular activity” in the body in the first two minutes post-exercise. In those first minutes, molecular markers of inflammation, tissue healing, and oxidative stress, which is a byproduct of metabolism, rose sharply.
Further, in the first couple of minutes, molecular markers suggested the body tended to metabolize amino acids for energy, but then switched to the sugar glucose at about 15 minutes after the workout. “The body breaks down glycogen [a form of stored glucose] as part of its exercise recovery response, so that's why we see that spike a little later,” Snyder said.9
Could a Blood Test Reveal Your Level of Fitness?
A strong correlation was found among a set of molecules and an individual's aerobic fitness level, leading the researchers to suggest it may be possible to use a blood test to monitor fitness level.
Among those who performed better on the treadmill endurance test, which measured peak V02, a measure of your body's ability to transport and use oxygen, which serves as a proxy for aerobic fitness, thousands of molecules were correlated with aerobic fitness level.
This includes molecules serving as markers of immunity, metabolism, and muscle activity. “At this point, we don't fully understand the connection between some of these markers and how they are related to better fitness,” Snyder said, and such molecular profiling would be too expensive and extensive for doctors to use in clinics at this point in time.
However, with further research, it may be possible to detect which biomarkers are most useful for determining fitness level based on those that are most highly correlated with peak VO2 results.10
“It gave us the idea that we could develop a test to predict someone's level of fitness,” study author Kévin Contrepois, Ph.D., director of metabolomics and lipidomics in Stanford's Department of Genetics, said. “Aerobic fitness is one of the best measures of longevity, so a simple blood test that can provide that information would be valuable to personal health monitoring.”11
While other fitness tests exist — grip strength, for instance, may be associated with your risk of heart attack and stroke — a blood test for fitness would allow you to monitor how changes in your fitness routine are working, and adjust accordingly.
Extend Your Lifespan in Just Minutes a Day
The featured study's findings are impressive, in part because of the magnitude of changes prompted by just one brief session of exercise. “I had thought, it's only about nine minutes of exercise, how much is going to change?” Snyder said. “A lot, as it turns out.”12
In terms of “bang for your buck” when it comes to your health, exercise is one of the most effective uses of time. The biochemical changes induced by exercise are well established and may affect the following pathways, influencing cancer risk and more:13
Insulin-like growth factor | Epigenetic effects on gene expression and DNA repair | HIF 1-alpha |
Oxidative stress and antioxidant pathways | Heat shock proteins | Testosterone |
Negative regulator of myostatin | Immunity | Chronic inflammation and prostaglandins |
Energy metabolism | Insulin resistance |
Research has also shown that exercising for 15 minutes a day, or an average of 92 minutes per week, lowers all-cause mortality by 14% and extends life expectancy by three years compared to being inactive.14 This was true even among people with risk factors for cardiovascular disease, and every additional 15 minutes of daily exercise reduced all-cause mortality by another 4%.
On the other hand, people who were inactive had a 17% increased risk of mortality even compared with those who exercised for just 15 minutes a day. This means that you don't have to log two hours on the treadmill or at the gym to get meaningful results — beneficial changes happen in far less time. Researchers are still pinning down the extent of these changes, but when they encompass 9,815 molecules, suffice to say they're significant.
Lack of time is one of the most common excuses used for not exercising, but the changes in the featured study occurred in about 10 minutes. Other studies have found exercise benefits after just seven minutes of moderate-intensity activity, including improvements in muscle strength, endurance and aerobic fitness.15
A sample circuit-style workout, developed by Brett Klika, a performance coach for the Human Performance Institute in Orlando, Florida, and Chris Jordan, the director of exercise physiology at the Human Performance Institute, is as follows.16
Each exercise is performed for about 30 seconds with 10 seconds allowed for transitions. This adds up to an approximately seven-minute workout, which may be repeated in its entirety two or three times. The exercises should be done in the order given, as they're selected to allow opposing muscle groups to alternate between resting and working, but give an example of how you can fit in exercise even if you're at home and/or very short on time.
- Jumping jacks (total body)
- Wall sit (lower body)
- Pushup (upper body)
- Abdominal crunch (core)
- Step-up onto a chair (total body)
- Squat (lower body)
- Triceps dip on a chair (upper body)
- Plank (core)
- High knees/running in place (total body)
- Lunge (lower body)
- Pushup and rotation (upper body)
- Side plank (core)
A New Era of Exercise Science
As researchers delve deeper into how molecular biology intersects with exercise physiology, there will be exciting advancements in understanding how exercise is crucial to human health. Exercise science has entered a new era,17 and using metabolomics and other omics technologies, researchers will likely be able to advance to more personalized exercise interventions, rather than generic recommendations like “get at least 150 minutes of exercise per week.”
Already, more specialized techniques like blood flow restriction (BFR) training are being adopted by the NFL and other major professional sports organizations for recovery and rehabilitation. BFR training improves strength and builds muscle using very light weights, while, metabolically, it decreases your risk for sarcopenia and most other age-related diseases, making it particularly useful for the elderly.
Other types of exercise, like yoga, with its unique combination of physical movement, breathwork, and meditation, may be particularly beneficial for brain function,18 while other more targeted exercises, like deadlifts, also have their place.
The Stanford University researchers are following up on their study with plans to establish whether molecular data could be used to determine which types of exercise, such as resistance or endurance training, are best for individuals, as certain people may have higher aerobic endurance, for instance, while others have a molecular profile that may favor a different type of training.19
For now, since such individualized targeting isn't available, the important take-home message to remember is just how immense the effect of exercise is on your body at an individual level. It's important to take advantage of its massive health-boosting potential by getting active and making physical fitness a regular part of your life.