Cardiorespiratory fitness and health
• CRF and all-cause mortality, CVD, cancer, obesity, diabetes mellitus, mental health
• Fat-but-fit Paradigm
• Health outcomes: biological mechanisms
Sedentary Behavior
• Definition
• Patterns of sedentary behavior
• Sedentary behavior in numbers
• USA
• Europe (Eurobarometer)
• Portugal
• Canadian 24-hour movement guidelines
• Early ages (0-4 years)
• Children and youth (5-17 years)
• Adults (18-64 years)
• Older Adults (≥ 65 years)
Sedentary Behavior and Health
• ST, breaks of ST, and all-cause mortality
• ST, breaks of ST, and comorbilities
Blair, S. N. et al (1989). Physical Fitness and All-Cause Mortality. JAMA, 262(17), 2395-2401
MEN
WOMEN
Blair, S. N. et al (1989). Physical Fitness and All-Cause Mortality. JAMA, 262(17), 2395-2401
Myers et al. (2002). Exercise Capacity and Mortality among Men Referred for Exercise Testing. NEJM, 346, 793-801.
Exercise capacity is a
more powerful
predictor of mortality
among men than other
established risk factors
for cardiovascular
disease
Myers et al. (2002). Exercise Capacity and Mortality among Men Referred for Exercise Testing. NEJM, 346, 793-801.
The risk of death from
any cause in subjects
whose exercise
capacity was less than
5 MET was roughly
double that of subjects
whose exercise
capacity was more than
8 MET
Myers et al. (2002). Exercise Capacity and Mortality among Men Referred for Exercise Testing. NEJM, 346, 793-801.
Imboden et al. (2018). Cardiorespiratory Fitness and Mortality in Healthy Men and Women. J Am Coll Cardiol, 72(19), 2283-2292.
Imboden et al. (2018). Cardiorespiratory Fitness and Mortality in Healthy Men and Women. J Am Coll Cardiol, 72(19), 2283-2292.
•
Obtaining a moderate fitness level for one’s age and sex is associated
with lower risk of early mortality from all-causes, CVD, and cancer
compared with those with low-fitness
•
Greater magnitude of the association observed when obtaining high
fitness
•
1-MET increment in cardiorespiratory fitness was associated with a
considerably lower all-cause (12%), CVD (16%), and cancer mortality
(14%) independent of traditional risk factors
This has important public health relevance as participation in regular exercise
meeting current recommendations has been shown to be capable of increasing CRF
by 1 to 2 METs, especially for those with low fitness
Imboden et al. (2018). Cardiorespiratory Fitness and Mortality in Healthy Men and Women. J Am Coll Cardiol, 72(19), 2283-2292.
Imboden et al. (2018). Cardiorespiratory Fitness and Mortality in Healthy Men and Women. J Am Coll Cardiol, 72(19), 2283-2292.
Both cardiorespiratory and muscular fitness have shown to be associated with
traditional and emerging CVD risk factors. Also both seem to have a combined
and accumulative effect on cardiovascular profile in young people.
Ortega et al. (2008). Physical fitness in childhood and adolescence: a powerful marker of health. Int J Obesity, 32, 1-11.
Each 1-MET increment in cardiorespiratory fitness was associated
with a 5% relative reduction in T2DM risk
Zaccardi et al. (2015). Cardiorespiratory fitness and risk of type 2 diabetes mellitus: A 23-year cohort study and a meta-analysis of prospective studies. Atherosclerosis, 243(1), 131-137.
Kurl et al. (2018). Cardiorespiratory fitness and risk of dementia: a prospective population-based cohort study. Age and Ageing, 47(1), 611-614.
Ross et al. (2016). Circulation;134:e653–e699. DOI: 10.1161/CIR.0000000000000461
Conclusions and Recommendations: CRF as a Predictor of Health Outcomes
• CRF is as strong a predictor of mortality as established risk factors such as cigarette
smoking, hypertension, high cholesterol, and T2DM.
• A CRF level <5 METs in adults is associated with high risk for mortality; CRF levels >8 to
10 METs are associated with increased survival.
• More than half the reduction in all-cause mortality occurs between the least fit (eg,
CRF <5 METs) group and the next least fit group (e.g. CRF 5–7 METs).
• Small increases in CRF (eg, 1–2 METs) are associated with considerably (10% to 30%)
lower adverse cardiovascular event rates.
• Efforts to improve CRF should become a standard part of clinical encounters (eg, an
accepted “vital sign”).
Ross et al. (2016). Circulation;134:e653–e699. DOI: 10.1161/CIR.0000000000000461
Ortega FB, et al. Br J Sports Med January 2018 Vol 52 No 3
Lifestyle intervention programs for obesity with special focus on exercise and a
healthy diet are important public health goals. However, focus should not be
placed exclusively on losing weight/fat, but also on increasing cardiorespiratory
fitness, since a medium–high cardiorespiratory fitness level may attenuate the
adverse consequences of obesity on health.
Ortega FB, et al. Br J Sports Med January 2018 Vol 52 No 3
• Men who maintained or
improved adequate physical
fitness were less likely to die
from all causes and from
CVD than persistently unfit
men
• Physicians should encourage
unfit men to improve their
fitness by starting a physical
activity program
Blair et al. (1995). Changes in Physical Fitness and All-Cause Mortality. JAMA, 273(14), 1093.
CRF is directly influenced by the hemodynamic
determinants of the Fick equation:
VO2 = Qc * a-vO2 difference
(oxygen uptake = cardiac output times the
arteriovenous difference for oxygen)
Cardiac output is determined by the product of HR
and stroke volume
Exercise Contribute to the Increase in CRF
• Habitual endurance-type exercise produces a variety of biological adaptations that lead to an
increase in peak/maximal CRF, primarily because of an increase in stroke volume and a decrease
in venous oxygen content resulting from an increase in O2 extraction in the trained muscle.
•
CRF can be increased in most people by regularly performing rhythmic contractions of large
muscle groups continuously for an extended period of time at a moderate or vigorous intensity
or with recovery breaks at lower intensity if the exercise approaches maximal effort.
Ross et al. (2016). Circulation;134:e653–e699. DOI: 10.1161/CIR.0000000000000461
Ross et al. (2016). Circulation;134:e653–e699. DOI: 10.1161/CIR.0000000000000461
Gronek et al. (2020). A Review of Exercise as Medicine in Cardiovascular Disease: Pathology and Mechanism. Aging and Disease, 11(2), 327-340.
Cardiorespiratory fitness and health
• CRF and all-cause mortality, CVD, cancer, obesity, diabetes mellitus, mental health
• Fat-but-fit Paradigm
• Health outcomes: biological mechanisms
Sedentary Behavior
• Definition
• Patterns of sedentary behavior
• Sedentary behavior in numbers
• USA
• Europe (Eurobarometer)
• Portugal
• Canadian 24-hour movement guidelines
• Early ages (0-4 years)
• Children and youth (5-17 years)
• Adults (18-64 years)
• Older Adults (≥ 65 years)
Sedentary Behavior and Health
• ST, breaks of ST, and all-cause mortality
• ST, breaks of ST, and comorbilities
Sedentary behavior is any waking behavior characterized by
an energy expenditure ≤ 1.5 METs, while in a sitting, reclining
or lying position
Tremblay et al. (2017). Sedentary behavior research network (SBRN) – Terminology Consensus Project process and outcome. Int J Behav Nutr Phys Activ, 14(1), 75
Tremblay et al. (2017). Sedentary behavior research network (SBRN) – Terminology Consensus Project process and outcome. Int J Behav Nutr Phys Activ, 14(1), 75
Sedentary jobs increased 83% since 1960 and physically active jobs
decreased 50%since 1960.
Church et al., PLoSONE, 6, e19657, 2011
If Physical Activity Is so Beneficial, Why Is Sedentary Behavior so
Alluring?
• Corner cutting is so common that it must be
hardwired into our biology.
• Walking across the corner, instead of staying
on the paved section, reduces the path of
travel by at most 1m.
• The time saving is about 1 s!!
Speakman et al., BioEssays 2019, 1900156
Putting things in perspective, what if?
• Imagine I am a hunter-gatherer walking 13–
21 000 steps per day
• There may be 200 or more occasions for
corner cutting
• So now I am walking 200m less and saving
200s every day.
• Over a whole year, that means I have saved
walking 73 km and about 20h and 15 min of
walking time
• The fact we still cut corners suggests that
there was a strong selective pressure for this
type of behavior to evolve
Speakman et al., BioEssays 2019, 1900156
What advantages may arise from sedentary behavior?
•
Over the hypothetical year of corner cutting, the
energy saving would amount to 1580 kcal.
•
Saving of 1500 kcal by cutting corners over the
course of a year is actually only 0.1–0.2% of the
total annual energy budget.
•
The risk of predation with at least 3 million years of
high predation risk before the invention of
weapons.
•
Twenty hours less activity per year from cutting
corners is about 1% less total activity, but this
would translate directly to a 1% reduction in
mortality risk when foraging, much more
important in terms of selection than a 0.1–0.2%
energy saving
•
Increased risk of injury.
Speakman et al., BioEssays 2019, 1900156
What implications does the fitness push to inactivity have for
modern humans?
•
Reducing activity levels whenever possible has probably
been under strong selection during our evolutionary
history.
Speakman et al., BioEssays 2019, 1900156
Sedentary behavior
Physical inactivity
Sedentary behavior is part of the same energy expenditure spectrum of
physical activity, whereas physical inactivity refers to non-compliance with
physical activity guidelines
Person A
Person B
Works in an office,
seated most of the
day
Spends the entire day
standing/walking at
work
But…
But…
Performs 1 hour per
day of physical
activity (i.e. > 150
min/wk of physical
activity)
Does not accomplish
the physical activity
guidelines
Physically active but also sedentary
Physically inactive but non-sedentary
27.5%
worldwide
physical
inactivity
Reducing the population levels of inactivity by 10% would save around half a million
lives annually
Methods: Evaluate the direct health costs, productivity losses and years of life with
disabilities (DALYs) associated with physical inactivity.
Results: Health care costs - 53.8 $ billion. Productivity losses related to mortality 13.7 billion. DALYs - 13.4 million worldwide.
Matthews et al. (2011). Accelerometer-measured dose-response for physical activity sedentary time, and mortality in US adults. Am J Clin Nutr, 104, 1424-1432.
Boys: 57.7%
Adults: 60.2%
Older adults: 65.2%
Girls: 61.1%
Adults: 56.5%%
Older adults: 63.8%
Santos et al. (2018). Patterns of accelerometer-derived sedentary time across the lifespan. J Sports Sci, 32, 1-9.
Troiano RP, et al. Br J Sports Med 2020;54:1468–1473. doi:10.1136/bjsports-2020-102621
Information provided by the Eurobarometer gathered through questionnaires
When asked about the amount of
time they spend sitting on a usual
day:
• 12% say they sit for more than 8
hours and 30 minutes
• 29% spend between 5 hours 31
minutes and 8 hours 30 minutes
sitting
• 40% sit for between 2 hours 31
minutes and 5 hours 30 minutes
• 16% only sit for 2 hours 30
minutes or less
Special Eurobarometer 472 – Report – Sport and Physical activity (2017-2018)
Information provided by the Eurobarometer gathered through questionnaires
When asked about the amount of time they spend sitting on a usual day:
•
•
•
•
10% say they sit for more than 8 hours and 30 minutes
24% spend between 5 hours 31 minutes and 8 hours 30 minutes sitting
39% sit for between 2 hours 31 minutes and 5 hours 30 minutes
23% only sit for 2 hours 30 minutes or less
Special Eurobarometer 472 – Report – Sport and Physical activity (2017-2018)
Early ages (0-4 years)
https://csepguidelines.ca/wp-content/themes/csep2017/pdf/PAR7972_24Hour_Guidelines_EY_En-4.pdf
Early ages (0-4 years)
https://csepguidelines.ca/wp-content/themes/csep2017/pdf/PAR7972_24Hour_Guidelines_EY_En-4.pdf
Children and youth (5-17 years)
https://csepguidelines.ca/wp-content/themes/csep2017/pdf/Canadian24HourMovementGuidelines2016_2.pdf
Adults (18-64 years)
https://csepguidelines.ca/wp-content/uploads/2020/10/24HMovementGuidelines-Adults18-64-2020-ENG.pdf
Older adults (≥ 65 years)
https://csepguidelines.ca/wp-content/uploads/2020/10/24HMovementGuidelines-Adults-65-2020-ENG.pdf
Older adults (≥ 65 years)
https://csepguidelines.ca/wp-content/uploads/2020/10/24HMovementGuidelines-Adults-65-2020-ENG.pdf
WHO, WHO guidelines on physical activity and sedentary behaviour. In: organization WH, ed. Geneva: World Health organization, 2020.
WHO, WHO guidelines on physical activity and sedentary behaviour. In: organization WH, ed. Geneva: World Health organization, 2020.
WHO, WHO guidelines on physical activity and sedentary behaviour. In: organization WH, ed. Geneva: World Health organization, 2020.
3)
Sardinha, L. B. and J. P. Magalhães (2012). "Comportamento Sedentário – Epidemiologia e relevância." Fatores de Risco 27: 54-64.
2h/d TV → RR = 1.13
Grøntved et al. (2018). Television Viewing and Risk of Type 2 Diabetes, Cardiovascular Disease, and All-Cause Mortality A Meta-analysis. JAMA, 305(23), 2448-2455.
Matthews e col. Amount of Time Spent in Sedentary Behaviors and Cause-specific Mortality in US Adults. The American Journal of Clinical Nutrition,95, 437-445, 2012.
Ekelund U, et al. Br J Sports Med 2020;54:1499–1507. doi:10.1136/bjsports-2020-103270
Ekelund U, et al. Br J Sports Med 2020;54:1499–1507. doi:10.1136/bjsports-2020-103270
Hetherington-Rauth et al. 2021
Key Points
•
Moderate-to-vigorous
physical
activity
(MVPA)
has
a
moderating effect on the relationship between sedentary time
(ST) and an older adult’s physical independence, such that
performing >36 min/d of MVPA was able to eliminate the
detrimental effects of ST.
•
Performing >108 min/d of MVPA promoted a positive effect of
ST on physical independence, indicating that for highly active
older adults, ST may in fact be beneficial for one’s ability to
maintain physical independence.
Hetherington-Rauth et al. 2021
2h/d TV → RR = 1.20
Grøntved et al. (2018). Television Viewing and Risk of Type 2 Diabetes, Cardiovascular Disease, and All-Cause Mortality A Meta-analysis. JAMA, 305(23), 2448-2455.
Less sedentary time is associated with better glucose control in T2DM. Reducing
sedentary time could be a simple adjunct therapy to improve glycemic control.
Paing et al. (2018). The associations of sedentary time and breaks in sedentary time with 24-hour glycaemic control in type 2 diabetes. Prev Med Rep, 12, 94-100.
2h/d TV → RR = 1.15
Grøntved et al. (2018). Television Viewing and Risk of Type 2 Diabetes, Cardiovascular Disease, and All-Cause Mortality A Meta-analysis. JAMA, 305(23), 2448-2455.
Every 1-h/day increase in TV viewing was associated with an increased
hazard for total (HR = 1.06), non-fatal CVD (HR = 1.06), and coronary heart
disease (HR = 1.08), independent of gender, age, education, smoking,
alcohol, medication, diabetes status, CVD family history, sleep duration and
PA energy expenditure
Sohn et al. (2008). Sedentary behavior and blood pressure control among osteoarthritis initiative participants. Osteoarthritis Cartilage, 22(9), 1234-1240.
•
The most sedentary quartile had
4.26 mmHg higher SBP than the
least sedentary quartile, adjusting
for age, MVPA, and other
demographic/health factors
•
The probability of having elevated
BP significantly increased in
higher sedentary quartiles
•
Reducing daily ST may improve
BP and reduction in CV risk
Sohn et al. (2008). Sedentary behavior and blood pressure control among osteoarthritis initiative participants. Osteoarthritis Cartilage, 22(9), 1234-1240.
Gilchrist et al. (2020). Association of Sedentary Behavior With Cancer Mortality in Middle-aged and Older US Adults. JAMA Oncology.
When expressed in tertiles, greater time spent in sedentary behavior and longer
mean sedentary bout duration were each associated with an increased risk of
cancer mortality
Gilchrist et al. (2020). Association of Sedentary Behavior With Cancer Mortality in Middle-aged and Older US Adults. JAMA Oncology.
Sedentary behavior was associated with increased colorectal (78%), endometrial
(34%), ovarian (66%), and prostate (39%) cancer risk
Lynch (2010). Sedentary Behavior and Cancer: A Systematic Review of the Literature and Proposed Biological Mechanisms. Cancer Epidemiol Biomarkers Prev, 19(11), 2691-2709.
WHO, WHO guidelines on physical activity and sedentary behaviour. In: organization WH, ed. Geneva: World Health organization, 2020.
Sedentary behavior pattern is the manner in which
sedentary behavior is accumulated throughout the day while
awake
Prolonger
Breaker
Someone who accumulates
sedentary time in extended
continuous bouts
Someone who accumulates
sedentary time with frequent
interruptions and short bouts
Tremblay et al. (2017). Sedentary behavior research network (SBRN) – Terminology Consensus Project process and outcome. Int J Behav Nutr Phys Activ, 14(1), 75
Breaker
Prolonger
Tremblay et al. (2017). Sedentary behavior research network (SBRN) – Terminology Consensus Project process and outcome. Int J Behav Nutr Phys Activ, 14(1), 75
•
Independent of total ST and MVPA time, increased breaks in ST were
beneficially associated with WC and BMI
•
Compared to those in the lowest quartile of breaks in ST, those in the highest
quartile had ± 5.95 cm lower WC
Healy et al. (2008). Breaks in Sedentary Time - Beneficial associations with metabolic risk. Diabetes Care, 31(4), 661-666.
Independent of total ST and MVPA time, increased breaks in ST were beneficially
associated with 2-h plasma glucose and TG.
Healy et al. (2008). Breaks in Sedentary Time - Beneficial associations with metabolic risk. Diabetes Care, 31(4), 661-666.
More frequent interruption in sedentary behavior are associated with better
glucose control in type 2 diabetes
Paing et al. (2018). The associations of sedentary time and breaks in sedentary time with 24-hour glycaemic control in type 2 diabetes. Prev Med Rep, 12, 94-100.
•
Older women who interrupt their ST more frequently are less likely to present
abdominal obesity
•
The odds for abdominal obesity decreased 7 % for each additional hourly
break in ST in women
Júdice et al. (2015). Associations of breaks in sedentary time with abdominal obesity in Portuguese older adults. Age (Dordr), 37(2), 23.
•
Physical function at older ages may be enhanced by breaking-up SB more
often, in addition to engaging in MVPA
•
The amount of daily BST was positively associated with physical function,
independently of total SB, MVPA, and other covariates
Sardinha et al (2015). Breaking-up Sedentary Time Is Associated With Physical Function in Older Adults. J Gerontol A Biol Sci Med Sci, 79(1), 119-124.
• The total volume of ST as well as how one accrues ST are both associated with allcause mortality
• PA guidelines should target reducing and interrupting ST to reduce mortality risk
Diaz et al. (2017). Patterns of sedentary behavior and mortality in U.S. middle-aged and older adults: A national cohort study. Ann Intern Med, 167(7), 465-475.
Sardinha, L. B. and J. P. Magalhães (2017). "Porque é necessário reduzir o tempo sentado? Mecanismos fisiológicos." Fatores de Risco 43: 32-40
Sardinha, L. B. and J. P. Magalhães (2017). "Porque é necessário reduzir o tempo sentado? Mecanismos fisiológicos." Fatores de Risco 43: 32-40
Hamilton e col., Diabetes, 56, 2655-2667, 2007
Judice e col., Eur J Appl Physiol, 116, 263–273, (2016)
• Continuous standing raised
MEC 5-8% above normal sitting
• The MEC from sit/stand
transitions is 27% higher than
continuous standing
• Neither sex nor FFM influenced
the results (p>0.05)
Judice e col., Eur J Appl Physiol, 116, 263–273, (2016)
Eight trained men, aged 20 to 30, performed 30 minutes of cycling at 75% of VO2peak,
followed by 90 minutes of high-intensity interval training (2-minute intervals at 50% and
90% of VO2peak until to exhaustion). Biopsies of the vast external were made immediately
after exercise and at different periods over time.
Magkos e col., Progress in Lipid Research, 48, 171–190, 2009
•
The study lasted between 14 - 20 days. The LPL protein mass was analyzed in 3 places, in
the control group and in the runner group (rectus femoris, solear and the masseter).
•
A difference of 179% in the mass of LPL protein was observed in the rectus femoris of the
runners compared to the sedentary control group
Hamilton e col., American Journal of Physiology and Endocrinology Metabolism, 275, E1016-E1022, 1998
The figures show the changes induced by the voluntary race in the LPL protein mass, in the LPL mRNA and LPL enzyme
activity, in the different types of muscles. Muscles composed mostly of white fibers recruited during the race
increased the LPL protein mass, LPL mRNA and LPL enzyme activity. The fact that the jaw muscle mRNA has not
changed during running shows that increased expression of LPL is specific to the contraction site.
Hamilton e col., American Journal of Physiology and Endocrinology Metabolism, 275, E1016-E1022, 1998
Hamilton e col., Diabetes, 56, 2655-2667, 2007
Dunstan et al. (2012). Breaking Up Prolonged Sitting Reduces Postprandial Glucose and Insulin Responses. Diabetes Care, 35, 976-983.
- 20%
Dunstan et al. (2012). Breaking Up Prolonged Sitting Reduces Postprandial Glucose and Insulin Responses. Diabetes Care, 35, 976-983.
Ritcher et al. (2013). Exercise, glut4, and skeletal muscle glucose uptake. Physiol Rev, 93, 993-1017.
Correia IR et al. (2021). Data not Published and under review.
Correia IR et al. (2021). Data not Published and under review.
•
Discussion: Frequent interruptions in
SB had no effect on PPG, prior or after a
2-week detraining. Conversely, older
adults experiencing a short-term
detraining period can use strategies,
such as breaking-up SB, in order to
potentially improve glycemic control.
•
Conclusions: Active older adults that
experience a short-term detraining
period may benefit from breaking-up
SB, to maintain their glycemic control.
Correia IR et al. (2021). Data not Published and under review.
Latouche et al. (2012). Effects of breaking up prolonged sitting on skeletal muscle gene expression. J Appl Physiol, 114, 453-460.
• Breaking up sedentary time
reversed the effects of chronic
inactivity on expression of 10
specific genes involved in
carbohydrate metabolism,
regulating the translocation of
the GLUT-4 glucose transporter
• Activity breaks (2 min of
activity for every 20 min of
sitting) increased the
expression of enzymes which
modulates anti-inflammatory
and anti-oxidative pathways
and triglyceride metabolism
Latouche et al. (2012). Effects of breaking up prolonged sitting on skeletal muscle gene expression. J Appl Physiol, 114, 453-460.
WHO, WHO guidelines on physical activity and sedentary behaviour. In: organization WH, ed. Geneva: World Health organization, 2020.