BITESIZE | What Hunter-Gatherers Can Teach Us About Movement, Exercise and Ageing Well | Professor Daniel Lieberman #624
Professor Daniel Lieberman discusses the evolutionary paradox of exercise, explaining that humans didn't evolve to "exercise" but to be physically active out of necessity or reward. He challenges common beliefs, highlighting that inactivity is harmful and offers practical ways to build sustainable movement habits by integrating purpose into daily life.
Deep Dive Analysis
9 Topic Outline
The Paradox of Exercise: Why We Struggle to Move
The Evolutionary Origin of 'Exercise'
The Instinct to Conserve Energy
Medicalizing Exercise vs. Natural Movement
Human Evolution: Activity and Longevity
Inactivity as an Evolutionary Mismatch
Rethinking the 10,000 Steps Guideline
Understanding Exercise Benefits and Vulnerability
Finding Purpose in Physical Activity
5 Key Concepts
Exercise (modern definition)
Voluntary, discretionary physical activity planned specifically for the sake of health and fitness, which is a completely modern idea alien to our ancestors.
Evolutionary Mismatch
A disease or condition that is more common or severe because our bodies are inadequately or imperfectly adapted for a novel environment, such as the modern lack of physical activity.
Selective Shadow
A term describing the period after an organism stops reproducing, during which natural selection no longer actively works to keep it alive, as it primarily cares about offspring production.
Healthspan
The number of years an individual lives without entering a period of chronic disability or disease, which is distinct from their overall lifespan.
Grandparent Hypothesis
The theory that humans evolved to live long lives after reproduction because grandparents play a crucial role in supporting their children and grandchildren through physical activity and knowledge transfer.
7 Questions Answered
We didn't evolve to do 'exercise' (voluntary, discretionary physical activity for health); our ancestors conserved energy and only moved when necessary or rewarding.
No, the idea of voluntary, planned physical activity solely for health and fitness is a completely modern concept, alien to most pre-industrial societies.
Humans evolved to live long lives after reproduction because grandparents play a vital role in foraging and supporting their children and grandchildren, a concept known as the grandparent hypothesis.
No, physical activity reduces vulnerability and risk for many diseases like heart disease and diabetes, but it does not prevent them entirely.
The 10,000 steps target originated from a Japanese accelerometer created before the 1964 Olympics, where 10,000 was considered an auspicious number in Japanese culture, not from a precise medical prescription.
While more steps are generally better for heart disease risk without a clear upper limit, benefits for all-cause mortality tend to plateau around 7,000 steps per day, though this varies greatly by individual.
Physical activity triggers repair and maintenance mechanisms in our bodies that help increase our healthspan and lifespan, a benefit that was selected for in human evolution because we evolved to be highly active.
13 Actionable Insights
1. Prioritize Daily Movement
Understand that while humans didn’t evolve for formal “exercise,” consistent daily movement is crucial for living well and overall health.
2. View Inactivity as Harmful
Reframe your perception of physical activity by considering inactivity as detrimental, akin to “poison” or “not having air,” rather than solely focusing on exercise as a “good” thing.
3. Avoid Self-Blame for Inactivity
Recognize that struggling with regular physical activity is normal and not a personal failing, as humans evolved to avoid unnecessary energy expenditure; avoid self-blame and guilt.
4. Find Purposeful, Enjoyable Movement
Reframe physical activity by finding ways to make it purposeful and enjoyable, such as playing sports or walking with friends, rather than viewing it as a chore done solely for “exercise.”
5. Integrate Rewarding Movement
Incorporate physical activity that is either necessary or genuinely rewarding (like play, purposeful work, or a race) into your life to overcome the natural instinct to avoid unnecessary movement.
6. De-medicalize Physical Activity
Shift your mindset away from viewing exercise as a “medicine” or a “pill” to be taken, as this approach often makes it feel like an unpleasant chore and reduces adherence.
7. Embrace Any Level of Movement
Dispense with the belief that only extreme exercise is beneficial; understand that “some exercise is better than none,” and even small increases in activity provide benefits.
8. Increase Incidental Movement
Incorporate small, consistent increases in daily movement, such as taking the stairs or parking further away, as “anything is better than nothing” for improving health.
9. Aim for 7,000+ Steps Daily
Target at least 7,000 steps daily for most benefits regarding all-cause mortality, understanding that more steps (e.g., 15,000-20,000) may offer further advantages for specific conditions like heart disease.
10. Use 10,000 Steps as a Guide
If motivating, use the 10,000 steps per day goal as a general guideline to increase your daily movement, acknowledging its arbitrary origin but practical utility.
11. Reduce Vulnerability Through Activity
Understand that physical activity doesn’t prevent all diseases but significantly reduces your vulnerability to chronic conditions like heart disease and diabetes.
12. Stay Active in Older Age
Challenge the modern notion of sedentary retirement; remain physically active as you age, as this aligns with human evolution and helps maintain health and longevity.
13. Read “Exercised” Book
Read Professor Daniel Lieberman’s book “Exercised” to understand why physical activity is healthy and rewarding, despite humans not evolving to “exercise” in the modern sense.
5 Key Quotes
Why would anybody run if they didn't have to?
Daniel Lieberman (quoting a Taramara elder)
We evolved to avoid physical activity, except for two reasons, for when it's necessary, or when it's rewarding.
Daniel Lieberman
Instead of thinking of exercise as medicine, I would think of inactivity as being like poison or like not having air.
Daniel Lieberman
Nothing makes sense in biology, except in the light of evolution. You could actually say nothing makes sense except in the light of evolution.
Daniel Lieberman
When you play a game of football or something, right, you're, you now have a purpose that's, and most people don't think of going for a walk with a friend or playing a game of sport. They don't always think of it as exercise, right? They think of it as, as you're playing a game of football or you're going for a walk with your friends and, and that gives it purpose.
Daniel Lieberman