Mike Joyner: Exercise, VO2 Max, and Longevity

Dr. Michael Joyner on Exercise and Longevity

• Lifelong interest in exercise and exercise physiology
• Exercise is a major factor in longevity, along with sleep, nutrition, emotional health, and exogenous molecules
• Exercise has the most impact on lifespan and health span

Why Exercise Helps You Live Longer

• Risk factors that contribute to cardiovascular disease and all-​​cause mortality are influenced by exercise and physical activity 
  • Blood pressure
  • Diabetes
  • Lipids and cholesterol
  • Stress management
  • Endothelial function (lining of blood vessels)
  • Autonomic nervous system (vagal tone, heart rate variability)
• Exercise has a synergistic effect on these risk factors, providing a greater benefit than the sum of the individual improvements
• Epidemiological studies consistently show a 50% reduction in cardiovascular and all-​​cause mortality among physically active individuals 
  • Examples: London bus driver/​​bus conductor study, longshoremen studies, Harvard alumni studies, Vasa Lopet cross-​​country ski race finishers

Natural Experiments in Epidemiology

• Comparing two groups of people exposed to different factors
• Consistent findings of a 50% reduction in cardiovascular and all-​​cause mortality among physically active individuals
• Exercise and physical activity lead to increased life expectancy
  Exercise and Aging
• Consistent small risk reductions in mortality for vegetarians 
  • Likely due to health-​​conscious choices in other areas of life
• Exercise has a more profound impact on health and longevity 
  • Hazard ratio of 0.5 (50% reduction in all-​​cause mortality)
  • Translates to a 3–5 year increase in life expectancy
  • 6–8 years of improved healthspan (disability-​​free years)

Natural Experiments in Exercise

• Bus conductor vs. bus driver study 
  • Conductors had more physical activity, less likely to make poor health choices
• Exercise can offset declines in physical ability more than sleep, nutrition, or medication

Centenarian Decathlon

• Model for measuring healthspan 
  • Focuses on athletic events and activities of daily living in the last decade of life
  • Examples: walking 3 miles in 1 hour, climbing 60 stairs in 1 minute, carrying 20 pounds of groceries, getting up off the floor with one hand of support

Decline in Performance with Age

• Decline can start at age 30 without training, pushed back to age 40 with training
• Steeper decline in the mid-​​70s, shifting from cardiopulmonary limitation to skeletal muscle strength and frailty 
  • 70% of 70-​​year-​​olds can’t get off the floor
• Importance of strength, circuit, and agility training in the 40s and 50s

Maintaining Activity and Strength in Aging

• At age 75, there is a steep decline in physical activity, muscle mass, and strength 
  • Loss of strength likely contributes to loss of activity, creating a feedback loop
• Importance of exercising relatively hard a few days a week to slow decline
• Avoiding inactivity is crucial for maintaining physiological function

Dangers of Falls in Later Life

• High mortality rate for 65+ year-​​olds who suffer a fall resulting in hip or femur fracture 
  • 25–60% mortality rate at one year, depending on the study
  • Exercise can help prevent falls and maintain bone mineral density
    Impact of Exercise on Health and Autonomic Nervous System
• Major health events, like a broken hip, can significantly impact the survival and quality of life of older individuals 
• Epidemiologist Lester Breslow identified factors in people who lived to 90:
• Non-​​smokers
• Not obese
• Physically active
• Ate modestly
• Stayed engaged in life
• Exercise can help maintain a healthy weight and counteract a bad diet
• However, it is difficult to outrun a bad diet in a modern, high-​​calorie, low-​​physical activity world

Autonomic Nervous System

• Controls the internal environment (homeostasis)
• Two branches: sympathetic nerves and parasympathetic nerves
• Sympathetic nerves: increase heart rate, constrict blood vessels, help muscles contract harder, make you sweat
• Parasympathetic nerves (e.g., vagus nerve): slow heart rate, lower blood pressure, critical for digestion
• Exercise helps tune up the autonomic nervous system, improving its ability to regulate the internal environment

Exercise and Recovery

• During exercise, blood pressure and heart rate increase to meet the demands of the skeletal muscles
• This is a normal response to generate a large cardiac output
• After exercise, heart rate and blood pressure fall, often to better levels than in untrained individuals

Heart Rate Recovery (HRR) and Heart Rate Variability (HRV)

• HRR: how quickly heart rate returns to baseline after exercise
• Faster HRR indicates better vagal nerve function, which is protective against arrhythmias and sudden cardiac events
• HRV: variation in time between heartbeats
• Indirect marker of vagal tone or activity
• Can be quite genetic and less modifiable than other factors
  Training and Mortality Risk
• Training and physical fitness can be measured in met hours per week 
  • Met: metabolic expenditure of sitting at rest (3.5 oxygen ventilation)
  • Example: Running 6 miles in an hour = 10 met hours
• Epidemiology suggests a J‑curve relationship between training and mortality risk 
  • Sedentary individuals have the highest risk
  • Moderate exercise reduces risk
  • Extremely high levels of exercise (e.g., 100 met hours per week) may increase risk

Vo2 Max Test and Mortality

• Vo2 max test measures oxygen consumption during exercise 
  • Higher Vo2 max = greater physical fitness
  • Strongly linked to all-​​cause mortality
• Fitter individuals have lower mortality risk 
  • Hazard ratio of 5.4 between fittest 2.5% and least fit 25%
  • Fitness is a more significant risk factor than smoking or end-​​stage renal disease
• Exercise is not a complete vaccine against health issues 
  • Can still have plaque buildup in coronary arteries
  • Blood vessels can be larger and healthier with exercise
  • Protective effect on lipids and blood vessel linings

Met Hours and Exercise Intensity

• Walking 3 miles in an hour: 3–4 met hours
• Running 6 miles in an hour: 10 met hours
• Example: Running 6 miles in an hour, 4 times a week = 40 met hours per week
• Extremely high levels of exercise (e.g., 100 met hours per week) may increase mortality risk according to some literature 
  • However, this is still debated and not universally agreed upon
    J Curve in Exercise and Mortality
• Mortality decreases with increased exercise up to a certain point, then increases again 
  • Some studies show a J curve, others do not
  • Large NCI study with 650,000 subjects did not show a J curve
  • Cross country ski paper from Scandinavia supports high levels of exercise without increased mortality

Atrial Fibrillation and Exercise

• Heavy exercisers may have a slightly increased risk of atrial fibrillation 
  • No increased risk of fatal arrhythmias
  • Ventricular arrhythmias, which can be fatal, are not seen more in heavy exercisers
  • Atrial fibrillation risk still lower than sedentary, hypertensive, obese, diabetic individuals
  • Good treatments available for atrial fibrillation

Myocardial Fibrosis and Exercise

• No compelling evidence to suggest myocardial fibrosis in heavy exercisers 
  • Flexible, compliant heart muscles seen in fit young people and master athletes
  • Training helps maintain ventricular compliance and flexibility

VO2 Max and Exercise

• VO2 max declines about 10% per decade starting in the 30s 
  • Decline driven by age-​​related decline in heart rate and reduced heart pumping capacity
  • Training can reduce the rate of decline by about half up to the 70s
  • Maintaining high VO2 max in youth can help offset the decline in later years

Training for High VO2 Max

• High-​​intensity training necessary to achieve high VO2 max 
  • Longer intervals three or four times a week can provide significant benefits
  • Maintaining high VO2 max can extend life and improve quality of life in later years
    VO2 Max and Aging
• VO2 Max: measure of maximum oxygen consumption during exercise 
• Important for maintaining independence and physical abilities as we age

VO2 Max in Older Adults

• A VO2 Max in the 20s or lower 30s is considered good for someone in their 80s
• Scandinavian elite skiers in their 80s had VO2 Max values in the high 30s or low 40s 
  • Likely due to genetic gifts and lifelong physical activity
• Aiming for a VO2 Max of 30 is a reasonable goal for older adults

Strength and Stability Training

• Important to train strength and stability alongside cardiovascular fitness
• Being able to perform daily activities and maintain independence is key 
  • Examples: playing with grandchildren, navigating stairs or escalators

Factors Affecting VO2 Max

1. Gas exchange in the lung
2. Pump efficiency (heart rate, stroke volume, contractility, etc.)
3. Gas exchange in the muscle bed 
4. Majority of reduction in VO2 Max as we age comes from reduced cardiac output 
   • Mainly due to reduction in peak heart rate
   • Can be buffered to some extent with a compliant ventricle

Training for VO2 Max

• Elite athletes often have lower peak heart rates due to high stroke volume
• Training can help maintain or improve VO2 Max as we age
• Important to find a balance between cardiovascular, strength, and stability training
  High Output Endurance Athletes
• Low-​​end aerobic efficiency is important for peak performance 
  • Example: Tadej Pogačar’s ability to maintain 4 watts per kilo for 4 hours
• Wider base of aerobic efficiency allows for a higher peak

Training Intensity Levels

• Elite athletes typically follow a 60–70–20–30–10 model 
  • 60–70% of time spent in medium-​​fast intensity (Zone 2/​​3)
  • 20% of time spent in slightly higher intensity (Zone 3)
  • 10% of time spent in high intensity (Zone 4/​​5)
• Training has converged on this model over the past 20 years

Benefits of Different Training Zones

• Zone 1 (recovery pace) has health benefits and is used for recovery between intervals 
  • Examples: slow walking, walking the dog, parking farther away in a parking lot
• Zone 2/​​3 (medium-​​fast intensity) is where most elite athletes spend their time 
  • Builds mitochondrial efficiency
• Zone 4/​​5 (high intensity) is used for pushing limits and improving peak performance

Training Volume for Elite Athletes

• Example: Eliud Kipchoge runs 14–18 hours per week 
  • 60–70% of time spent in medium-​​fast intensity (Zone 2/​​3)
  • 20% of time spent in slightly higher intensity (Zone 3)
  • 10% of time spent in high intensity (Zone 4/​​5)
• Training volume has not changed much for elite athletes over the past 50–60 years 
  • Improvements in performance mostly due to better equipment, races, sports medicine, and longer careers
    Health Benefits of Light Exercise
• Substantial health benefits from light physical activity 
• Biggest benefit comes from the first 10–15 minutes a day 
  • Improves insulin sensitivity, fights against diabetes
  • Provides a buffer against weight gain
  • Improves blood vessel lining and autonomic function

Using Metrics to Track Exercise Progress

• Heart rate recovery and heart rate variability can be useful metrics
• Rating of perceived exertion (RPE) can also be helpful 
  • Helps individuals learn to read their own body
• Focus on big picture aspects of exercise 
  • Total minutes of activity per day
  • Balance of high-​​intensity and moderate-​​intensity exercise
  • Incorporating other forms of activity (e.g., taking stairs)

Example Exercise Regimen

• Hard day: Circuit training, stationary bike intervals, drop sets for major muscle groups
• Easy day: 30–40 minutes of light cycling or rowing, active rest
• Alternating hard and easy days for optimal recovery and progress

Boosting VO2 Max

• 4x4 or 4‑on‑4 protocol: 4 minutes of high-​​intensity exercise followed by 4 minutes of rest 
  • Can be done on a bike, on an incline, or with other forms of exercise
  • Focus on maintaining steady power output and heart rate
  • Aim to push through dips in performance during the third minute
    Interval Training and VO2 Max
• Interval training can help boost VO2 max 
• For beginners, start with 80% of their time at a conversational but not enjoyable pace
• After building a reserve, introduce four hard intervals once a week (four minutes on, four minutes off)
• Eventually, increase to two hard sessions per week
• More than five or six hard sessions every two weeks can lead to load management issues

Training to Train

• Some individuals need to train before they can train hard
• Pretraining for 3–6 months may be necessary for older individuals or those new to exercise

Elite Athletes and Exceptional Performances

• Elite athletes used to have a finite number of exceptional performances
• Sports medicine advancements and professionalization have extended athletes’ careers
• Age of Olympians has increased, allowing for longer careers and more exceptional performances
  Performance Enhancing Drugs in Sports
• Athletes can monetize their careers, leading to longer participation in sports 
• Tom Brady’s career would have been over in 2009 without advancements in orthopedic surgery
• NBA, NFL, and MLB salary scales motivate athletes to play longer for millions of dollars

Doping in Sports

• Industrial strength doping era is over 
  • Testing has improved in frequency and chemistry
  • Micro-​​dosing still possible
• Novel compounds, small peptides, and difficult-​​to-​​detect substances still a concern
• Industrial strength doping has been replaced by low-​​dose doping and manipulation

Growth Hormone in Sports

• Growth hormone may still be used in sports
• Athletes may use low-​​dose, short-​​acting androgens and EPO-​​related compounds

Exercise Mimetics

• Pharmaceutical companies are researching exercise mimetics
• Current efforts focus on increasing mitochondrial biosynthesis
• Exercise mimetics may have limited benefits compared to actual exercise
• Polypill (low-​​dose statins, blood pressure meds, etc.) may provide some benefits similar to exercise
  Polypill for Lifestyle Diseases
• Polypill: a combination of medications that address multiple health issues 
  • Example: statin for cholesterol, metformin for glucose tolerance, beta blockers for heart rate
• Polypill could be a potential public health strategy for lifestyle diseases 
  • Encourages exercise and healthy habits
  • Understudied area

Sex Differences in Blood Pressure Regulation

• Research with Sarah Baker on sex differences in blood pressure regulation
• Interest in human performance

Hemoglobin Dissociation Curve

• Right shift: hemoglobin releases oxygen to tissues, harder to get oxygen from lungs 
  • Good for hypoxic situations
• Left shift: hemoglobin picks up oxygen from lungs at high altitude 
  • Found in animals adapted to high altitude (llamas, bar-​​headed goose)
  • Some humans have rare left-​​shifted hemoglobins

Convalescent Plasma Program

• Antibody-​​rich plasma from recovered COVID patients given to those with the disease 
  • Evidence of effectiveness when given early in the course of the disease
  • Helpful for immune-​​suppressed individuals
• Over 100,000 patients treated
• Plasma donors typically available 2–3 weeks after recovery, up to 6 months 
  • “Super donors” have both infection and vaccination, providing broader spectrum antibodies

Future of Physical Activity in America

• Need for increased physical activity and access to resources 
  • Disparity in access to coaching, facilities, and programs
  • Decline in unstructured play and opportunities for physical activity
• Importance of addressing societal issues to improve overall health and physical activity levels
  Open Gym and Physical Activity
• Open gym in Tucson provided a safe space for high-​​energy kids 
  • Police knew where they were, making their job easier
  • Beneficial for athletes and community
• Lack of open gym in Rochester, Minnesota 
  • Rich community, but limited access to facilities
• Suggestion for a national open gym movement 
  • Winter and summer, making use of existing facilities

Mandatory Physical Activity

• Idea of mandatory 1‑hour activity for everyone 
  • Could be exercise, gym, or just walking
• Example of secretaries walking during lunch break 
  • Social event, problem-​​solving, and increased productivity

Future Plans and Connections

• Attia plans to continue reading Mike’s work
• Hopes to meet in person and work out together
• Mention of Eddie Coyle at the University of Texas 
  • Potential future podcast guest