In the most comprehensive study to date of the molecular changes that occur in your body due to exercise, researchers have seen “an orchestrated choreography of biological processes.”
Researchers at Stanford University found that one exercise session leads to changes in a remarkable 9,815 molecules in your blood.[1]
The findings reveal exercise does far more than simply raise your heart rate and cause 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.
‘Omics’ Reveals Molecular Choreography
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, researchers look at molecular changes across a large swath of the body’s vast biochemical systems before and after 36 people exercised.
- Energy metabolism
- Oxidative stress
- Inflammation
- Tissue repair
- Growth factor response
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, professor and chair of genetics at Stanford University, said in a statement. “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.
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.
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.Thousands of molecules were correlated with aerobic fitness level, researchers found, after looking at those who performed better on a treadmill endurance test. The test measured peak VO2 as a proxy for aerobic fitness. This test measures your body’s ability to transport and use oxygen.
Molecules linked to fitness also serve 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. There is also limited application of that insight, should it develop, given that such molecular profiling would currently be too expensive and extensive for doctors to use in clinics.
However, with further research, it may be possible to detect which biomarkers are most useful for determining fitness levels 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, 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]
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]- Insulin-like growth factor
- Epigenetic effects on gene expression and DNA repair
- HIF 1-alpha
- Oxidative stress and antioxidant pathways
- Testosterone
- Negative regulator of myostatin
- Immunity
- Chronic inflammation and prostaglandins
- Energy metabolism
On the other hand, people who were inactive had a 17 percent 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.
The Workout
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]- Jumping jacks (total body)
- Wall sit (lower body)
- Pushup (upper body)
- Abdominal crunch (core)
- Step-up onto chair (total body)
- Squat (lower body)
- Triceps dip on 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.”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.
- 1, 4, 5 Cell. 2020 May 28;181(5):1112-1130.e16. doi: 10.1016/j.cell.2020.04.043.
- 2 Occup Environ Med. 2010 Feb; 67(2): 136–143.
- 3, 6, 8, 12, 19 The New York Times June 10, 2020
- 7, 9, 10, 11 Stanford University May 28, 2020
- 13 Br J Sports Med. 2017 Apr; 51(8): 640–644.
- 14 The Lancet August 16, 2011
- 15, 16 ACSM'S Health & Fitness Journal May/June 2013 - Volume 17 - Issue 3 - p 8–13
- 17 Clin Chem. 2020;96:55-84. doi: 10.1016/bs.acc.2019.11.003. Epub 2019 Dec 18.
- 18 Brain Plasticity 2019; 5(1): 105-122