Physical Activity, Physical Fitness and Mental Health
13 de setembro de 2025 17:38
Lesson 1 - Physical activity and sedentary behaviour
PAFFMH_S
ession 1
Watch Mike Evans lecture: 23 and 1/2 hours: What is the single best thing we can do for our health?
Health is a state of complete physical, mental and social well-being and not merely the absence of disease or
infirmity
The leading causes of mortality include physical inactivity, accounting for 6% of premature deaths. Our humanitarian
evolution lead us to spending more time sedentary, involving a combination of low energy expenditure and low
physical activity
• A Jeremy Morris study (1958) found that people who go up and down the stairs in the bus decreased 50% of CV
caused deaths.
• Public health gains will be greatest when we help the least active become more active NOT by just making the
active even more active and by emphasising behaviours for many people (small changes across large populations)
Physical health is related to:
• Prevention and management of chronic conditions: cardiovascular disease, diabetes, musculoskeletal problems,
some cancers
• Improving and maintaining physical function: ADL, functional status, risk of falling, bone mineral density
Mental health and QoL is related to:
• Prevention and management of chronic conditions: Anxiety, depression, cognitive function
Social health is related to:
• Loneliness and social connectiveness
Concepts of health
Exercise: Planned, structured, repetitive and purposeful, resulting in improvement and maintenance of one of more
components of physical fitness.
• Inserted in the domain of leisure PA or occupation if athlete.
• Exercise is the medicine/cure for illness, in some case more effective than drugs.
Physical Fitness: The ability to perform muscular work satisfactorily due to a set of attributes that are either health or
skill related.
• Physical fitness has an effect on physiology and needs the right stimulus of the organ system
Sport: Competitive activity undertaken in the context of rules defined by an international regulatory agency
Physical activity: Bodily movement that is produced by the contraction of skeletal muscles that substantially increases
energy expenditure.
• Associated with better health
• Health outcome
• Involves different domains like occupational PA, household, transport, exercise, sport which have an effect on
mental health.
• PA is the prevention of illness and maintenance of health.
Courses and notes Page 1
, • PA is the prevention of illness and maintenance of health.
• Physical activity is an activity so it requires behavioral change intervention.
• Assessing, describing and evaluating PA is challenging because you need to take into account all the FIIT
parameters and the patient needs to have an accurate recall.
There are complex relations between PA, Health related fitness and Health that are affected by external factors and
genetics
We choose the interventions based on the assessment of the cause of disease/inactivity - PA or PF. Both PA and PF
have an impact in physical and mental health.
Sedentary behaviour: Any waking activity characterized by an energy expenditure ≤ 1.5 metabolic equivalents and a
sitting or reclining posture. It is different than simply a lack of moderate-to-vigorous PA (Increasing PA ≠ reducing
SB), so we should asses both physical activity habits and sedentary behaviour habits.
Energy expenditure and how to estimate it
10% - Diet induced energy expenditure: Absorption, digestion, transport, storage
25% - Physical activity or muscular activity
65% - RMR: resting metabolic rate - cardiac muscle, brain, kidney, pancreas, other organs
How to estimate energy expenditure?
MET = Metabolic Equivalent: The ratio of the work metabolic rate to the resting metabolic rate
• One MET is defined as 1 kcal/kg/hour and is roughly equivalent to the energy cost of sitting quietly
• A MET also is defined as oxygen uptake in ml/kg/min: 1MET equal to the oxygen cost of sitting quietly,
equivalent to 3.5 ml/kg/min
This measure is used in epidemiological studies and the MET values often used to estimate PA volume or energy
expenditure in studies using surveys to measure PA.
Courses and notes Page 2
,PAL = total daily EE (energy expenditure - add all the METs x duration) / RMR (resting metabolic rate - 24h x 1 MET).
• Average daily EE expressed as a multiple of 1MET
• Simple way to report PA level in one number and examine associations between PA and range of health outcome
• Typically ranges from 1.1 to 2.4
Physical activity and sedentary behaviour guidelines
Why guidelines?
• Public health messaging
• To monitor and promote population PA levels
The development of guidelines is a rigorous process, based on extensive review of available scientific epidemiological
literature and involvement of stakeholders. There are many guidelines (in different countries, for different age groups
and health status) but the main message is similar, with some nuances.
WHO guidelines
• Physical activity has significant health benefits for hearts, bodies and minds
• Physical activity contributes to preventing and managing noncommunicable diseases such as cardiovascular
diseases, cancer and diabetes
• Physical activity reduces symptoms of depression and anxiety
• Physical activity enhances thinking, learning, and judgment skills
• Physical activity ensures healthy growth and development in young people
• Physical activity improves overall well-being
• Globally, 1 in 4 adults do not meet the global recommended levels of physical activity
• People who are insufficiently active have a 20% to 30% increased risk of death compared to people who are
sufficiently active
• More than 80% of the world's adolescent population is insufficiently physically active
It is recommended that:
• All adults undertake regular physical activity
• Adults should do at least 150-300 min of moderate-intensity aerobic PA; or at least 75-150min of vigorous-
intensity aerobic PA; or an equivalent of moderate and vigorous intensity activity throughout the week, for
substantial health benefits
• Adults should also do muscle strengthning activities at moderate or greater intensity that involve all major
muscle groups on 2 or more days a week, as these provide additional health benefits
• Adults may increase moderate-intensity aerobic PA to more than 300 min; or do more than 150 min of vigorous
intensity aerobic PA
Courses and notes Page 3
, intensity aerobic PA
• Doing some physical activity is better than doing none
• If adults are not meeting these recommendations, doing some PA will benefit their health
• Adults should start by doing small amounts of PA, and gradually increase the frequency, intensity and duration
overtime
• Adults should limit the amount of time spent being sedentary. Replacing sedentary time with physical activity of
any intensity (including light intensity) provides health benefits
• To help reduce the detrimental effects of high levels of sedentary behaviour on health, adults should aim to do
more than the recommended levels of moderate- to vigorous-intensity PA
In this graph we see how physical activity can be incorporated in culture. Iceland is the only european country where
women are more physically active than men.
Be aware of the patterns of each individual (ex: elite athlete vs. childcare worker): Is it better to be sedentary for
many hours with peaks of moderate and vigorous activity vs sedentary for few hours and many peaks of light activity?
• For someone with low back pain we would prioritise having the least amount of time as sedentary.
• For someone with obesity and mental health issues it is usually recommended to have lighter consistent activity
levels in an enjoyable way even if we know that to lose weight it is more effective to do vigorous activity
Being active can be difficult because of the many factors involved in it!
Courses and notes Page 4
13 de setembro de 2025 17:38
Lesson 1 - Physical activity and sedentary behaviour
PAFFMH_S
ession 1
Watch Mike Evans lecture: 23 and 1/2 hours: What is the single best thing we can do for our health?
Health is a state of complete physical, mental and social well-being and not merely the absence of disease or
infirmity
The leading causes of mortality include physical inactivity, accounting for 6% of premature deaths. Our humanitarian
evolution lead us to spending more time sedentary, involving a combination of low energy expenditure and low
physical activity
• A Jeremy Morris study (1958) found that people who go up and down the stairs in the bus decreased 50% of CV
caused deaths.
• Public health gains will be greatest when we help the least active become more active NOT by just making the
active even more active and by emphasising behaviours for many people (small changes across large populations)
Physical health is related to:
• Prevention and management of chronic conditions: cardiovascular disease, diabetes, musculoskeletal problems,
some cancers
• Improving and maintaining physical function: ADL, functional status, risk of falling, bone mineral density
Mental health and QoL is related to:
• Prevention and management of chronic conditions: Anxiety, depression, cognitive function
Social health is related to:
• Loneliness and social connectiveness
Concepts of health
Exercise: Planned, structured, repetitive and purposeful, resulting in improvement and maintenance of one of more
components of physical fitness.
• Inserted in the domain of leisure PA or occupation if athlete.
• Exercise is the medicine/cure for illness, in some case more effective than drugs.
Physical Fitness: The ability to perform muscular work satisfactorily due to a set of attributes that are either health or
skill related.
• Physical fitness has an effect on physiology and needs the right stimulus of the organ system
Sport: Competitive activity undertaken in the context of rules defined by an international regulatory agency
Physical activity: Bodily movement that is produced by the contraction of skeletal muscles that substantially increases
energy expenditure.
• Associated with better health
• Health outcome
• Involves different domains like occupational PA, household, transport, exercise, sport which have an effect on
mental health.
• PA is the prevention of illness and maintenance of health.
Courses and notes Page 1
, • PA is the prevention of illness and maintenance of health.
• Physical activity is an activity so it requires behavioral change intervention.
• Assessing, describing and evaluating PA is challenging because you need to take into account all the FIIT
parameters and the patient needs to have an accurate recall.
There are complex relations between PA, Health related fitness and Health that are affected by external factors and
genetics
We choose the interventions based on the assessment of the cause of disease/inactivity - PA or PF. Both PA and PF
have an impact in physical and mental health.
Sedentary behaviour: Any waking activity characterized by an energy expenditure ≤ 1.5 metabolic equivalents and a
sitting or reclining posture. It is different than simply a lack of moderate-to-vigorous PA (Increasing PA ≠ reducing
SB), so we should asses both physical activity habits and sedentary behaviour habits.
Energy expenditure and how to estimate it
10% - Diet induced energy expenditure: Absorption, digestion, transport, storage
25% - Physical activity or muscular activity
65% - RMR: resting metabolic rate - cardiac muscle, brain, kidney, pancreas, other organs
How to estimate energy expenditure?
MET = Metabolic Equivalent: The ratio of the work metabolic rate to the resting metabolic rate
• One MET is defined as 1 kcal/kg/hour and is roughly equivalent to the energy cost of sitting quietly
• A MET also is defined as oxygen uptake in ml/kg/min: 1MET equal to the oxygen cost of sitting quietly,
equivalent to 3.5 ml/kg/min
This measure is used in epidemiological studies and the MET values often used to estimate PA volume or energy
expenditure in studies using surveys to measure PA.
Courses and notes Page 2
,PAL = total daily EE (energy expenditure - add all the METs x duration) / RMR (resting metabolic rate - 24h x 1 MET).
• Average daily EE expressed as a multiple of 1MET
• Simple way to report PA level in one number and examine associations between PA and range of health outcome
• Typically ranges from 1.1 to 2.4
Physical activity and sedentary behaviour guidelines
Why guidelines?
• Public health messaging
• To monitor and promote population PA levels
The development of guidelines is a rigorous process, based on extensive review of available scientific epidemiological
literature and involvement of stakeholders. There are many guidelines (in different countries, for different age groups
and health status) but the main message is similar, with some nuances.
WHO guidelines
• Physical activity has significant health benefits for hearts, bodies and minds
• Physical activity contributes to preventing and managing noncommunicable diseases such as cardiovascular
diseases, cancer and diabetes
• Physical activity reduces symptoms of depression and anxiety
• Physical activity enhances thinking, learning, and judgment skills
• Physical activity ensures healthy growth and development in young people
• Physical activity improves overall well-being
• Globally, 1 in 4 adults do not meet the global recommended levels of physical activity
• People who are insufficiently active have a 20% to 30% increased risk of death compared to people who are
sufficiently active
• More than 80% of the world's adolescent population is insufficiently physically active
It is recommended that:
• All adults undertake regular physical activity
• Adults should do at least 150-300 min of moderate-intensity aerobic PA; or at least 75-150min of vigorous-
intensity aerobic PA; or an equivalent of moderate and vigorous intensity activity throughout the week, for
substantial health benefits
• Adults should also do muscle strengthning activities at moderate or greater intensity that involve all major
muscle groups on 2 or more days a week, as these provide additional health benefits
• Adults may increase moderate-intensity aerobic PA to more than 300 min; or do more than 150 min of vigorous
intensity aerobic PA
Courses and notes Page 3
, intensity aerobic PA
• Doing some physical activity is better than doing none
• If adults are not meeting these recommendations, doing some PA will benefit their health
• Adults should start by doing small amounts of PA, and gradually increase the frequency, intensity and duration
overtime
• Adults should limit the amount of time spent being sedentary. Replacing sedentary time with physical activity of
any intensity (including light intensity) provides health benefits
• To help reduce the detrimental effects of high levels of sedentary behaviour on health, adults should aim to do
more than the recommended levels of moderate- to vigorous-intensity PA
In this graph we see how physical activity can be incorporated in culture. Iceland is the only european country where
women are more physically active than men.
Be aware of the patterns of each individual (ex: elite athlete vs. childcare worker): Is it better to be sedentary for
many hours with peaks of moderate and vigorous activity vs sedentary for few hours and many peaks of light activity?
• For someone with low back pain we would prioritise having the least amount of time as sedentary.
• For someone with obesity and mental health issues it is usually recommended to have lighter consistent activity
levels in an enjoyable way even if we know that to lose weight it is more effective to do vigorous activity
Being active can be difficult because of the many factors involved in it!
Courses and notes Page 4
