KNES 355 MIDTERM 1

what does somatic mean?

affecting the body, of the body

why do we study growth, maturation, and development?

to learn about normal pattern of biological variation at individual and population levels in human

what term does this describe:

how a childs growth varies over time

within subject variation

what is between subject and between group variation?

how do variables of growth, maturation, and development differ between children and by sex

what is between population variation

how do variables of growth, maturation, and development differ between population

what can be modified during growth and development?

physical, nutritional, training, and social environment (all contribute to human variation)

what is the purpose of modifications for growth and development?

to optimize a childs growth, health, and performance potential

what is human biological variability?

range of possible values for any measurable characteristics (physical) of humans at the level of individual, group, population

what is human biological variability influenced by?

genetics, prenatal environment, nutritional status, education, environment (cultural, social, familial), abuse/neglect

what is meant by somatic growth?

growth of the body

what can somatic refer to outside of “of the body”?

body cell of an organism (usually with diploid number of chromosomes in nucleus, growth of cell), tissues/organs or biological systems comprised of cells, gross morphological features (height, weight, BMI)

how do we see variability within an individual? What do we think about?

which factors explain somatic changes, magnitude and nature of differences may vary by age and sex

what are some practical applications of understanding human variability?

assess normalcy of G, M & D status (compare to reference charts, individual and group), assess normalcy of rates of change or progress, predict future outcomes (tracking), interpret effect of physical activity or exercise on biological outcomes

what are the stages of lifetime development?

pediatric (pre-natal, childhood), adulthood (young, middle, older)

what are the pediatric stages of lifetime development and what are their characteristics?

pre-natal (1st, 2nd, 3rd trimester), childhood (early, middle, late adolescence -puberty)

what are the adulthood stages of lifetime development and what are the age ranges?

young (19-40 years), middle (40-60 years), see menopause and andropause here, older (60+ years)

what are the stages of pediatric developmental periods?

<19 years, pre-natal, infancy, early childhood, mid-childhood, late childhood, adolescence (see puberty in late childhood and adolescence)

what is part of the pre-natal stage in pediatric development periods?

egg (twinning, fertilization occurs), embryo (sex and organ development, egg implants in uterine wall), fetus (growth)

what is part of the infancy stage in pediatric development periods?

birth to 1 years, peri-natal (1st week of living), neo-natal (1st month of life), post-natal (2 -12 months of living)

what is part of the early childhood stage in pediatric development periods?

1-5 years

what is part of the mid-childhood stage in pediatric development periods?

6-8 female, 6-10 male

what is part of the late-childhood stage in pediatric development periods?

9-10 female, 11-12 male

what is part of the adolescence stage in pediatric development periods?

11-19 female, 13-22 male

what is growth?

increase in size of the body as a whole and of its parts

what is maturation?

progress towards a biologically mature state, timing and tempo varies between individuals, organs and tissues, relates biological time to calendar time

what is development?

behaviour competence, learning appropriate behaviours expected by society (cognitive, emotional, social, moral and motor)

what does growth reflect?

quantitative change in size (ex:length, width, mass, volume, density)

what are the characteristics of growth?

overtime, within an individual, at any point in time between individuals, increase or decrease (not limited to childhood/adolescence), may also be associated with maturity (depending on age and physiological system)

what is growth status?

size attained at any point in time (based on age or maturity), compared with norms/references

why is growth status important?

one of the best indicators of overall health and nutrition, reflects genetics and environmental influences

what 3 underlying processes describe the process of growth and change in size or shape?

hyperplasia, hypertrophy, accretion (result in change in physical size and shape)

what is hyperplasia?

increase in cell number (more cells)

what is hypertrophy?

increase in cell size (larger cells, change in length, width, mass, volume and density)

what is accretion?

increase in interstitial material, more stuff within cells

what is growth in skeletal muscle tissue?

increase in muscle cell thickness and length doesnt equal increase in cell number, obvious change in tissue is due to cell growth (hypertrophy)

what is size?

a difference in physical magnitude, multi-dimensional at cell/tissue/body levels (ex: length, width, mass, volume and density)

how do we measure vs express size?

measure size quantitatively (absolute units), often express it relatively (larger or smaller)

what influences size in childhood?

mostly growth, tempo and rate of growth so also influenced by maturation

what influences size in adulthood?

primarily due to residual growth potential and usually ceases by mid-20s

what are some exceptions in how maturation or growth influence changes in size?

fat, muscle, and bone (changes can be positive or negative)- mass, volume, thickness, density

what is variation in size due to?

different factors at different stages of the lifespan

what is an example of size influences in sport?

study of NFL draftees and month of birth (greater than expected % born early in the year), due to relative age effect

when talking about the study of NFL draftees and month of birth and how this influenced size what is not true?

not due to maturing early but same effect

when talking about the study of NFL draftees and month of birth and how this influenced size why does the relative age effect occur? Why is it called the relative age effect?

born earlier means physically bigger during childhood because more time to grow so more coaching attention and more trained

what is the relative age effect as seen in sports?

over-representation of children born earlier in the year on elite junior teams, youth sport typically organized by chronological age, often creates an advantage for oldest children in the group, coaches may mistake greater physical growth for greater ability

how does the RAE create advantage for the oldest children in the group?

12 month difference between children born at the start vs end of the year

what are the implications of the relative age effect on older athletes?

more likely to be selected for elite teams, receive better coaching/training, experience more success, more likely to be viewed as gifted (self fulling prophecy)

what are the implications of the relative age effect on young athletes?

less likely to be selected for elite teams, more likely to fall behind or drop out, negative impact on self-perception (self-fulling prophecy)

what are some examples of size in relation to health and medical concerns? (psychological, physiological and medical concerns)

difficulty regulating temp, failure of somatic growth potential, behavioural difficulties, self-esteem, orthopaedic issues, risk of CV and metabolic disease

how does size relate to relative measures in health? What are some relative size measures/

body mass (BMI), fat mass (%fat), bone density

why is size important in health?

surrogate measure for underlying pathology

what is shape?

distribution of mass within an object, change in geometric proportionalities

does geometric shape and changes in shape of the body impact us?

has functional impacts

does body shape change with growth?

evident external age-related changes

what are the consequences of changes in body shape as we grow? What is one example?

young kids are more round which means more surface area so they overheat, female is wider and shallower than male

are there consequences to growth related changes in shape?

some changes result in altered biomechanical, thermoregulatory, physiological, and reproductive functions (change may be beneficial, neutral, or detrimental)

what does maturation refer to?

tempo and timing of physical changes, progress towards a mature state (maturation - process, maturity - status), distance travelled on the way to adulthood

what are references for adulthood in maturation?

adult status for height and other biological functions (ex: reproductive maturity, ability to care for and keep offspring alive)

when do most biochemical and physiological systems mature by?

early adulthood (~18 years)

what are the characteristics of maturation?

specific changes in tissues, organs, and systems, change may occur at different times and varies with biological system, usually measured by quantitative and qualitative changes

what is meant by specific changes in tissue, organs and systems in maturation?

secondary sex and skeletal characteristics

what is meant by changes can occur at different times in maturation?

secondary sex characteristics only at puberty, skeletal changes are continuous from before birth to adulthood

what is an example of qualitative vs quantitative measurements in maturation?

quantitative (number or size), qualitative (shape of bones or breasts)

how do growth vs maturation proceed?

growth (can proceed without changes in maturation), maturation (typically involves increased growth of some somatic feature)

what is development?

behavioural and biological contexts, learning appropriate behaviours expected by society (cognitive, emotional, social, moral, motor)

what is development in the biological sense?

continuous, age-related, sequential (orderly, irreversible stages)

what does growth refer to in comparison to development?

primarily refers to size, chiefly structural, easily measured (height, weight)

what does development refer to in comparison to growth?

primarily refers to complexity and progress, chiefly functional, more difficult to measure (neuromotor control, skill level, social behaviour)

even though change is constant during childhood what is key?

occurs at different times (between people), on different fronts (different parts of the body/tissue), at different rates with fairly predictable consequences

what are the characteristics of growth in non-primate mammals?

growth and development is smooth and continuous from birth to adulthood

what are the characteristics of growth in primate mammals? How does it differ from non-primate?

sexual development occurs long after infancy, neurological development (size of brain) is ~90% complete before a human can reproduce

what does scammons curve of systemic growth show you? What do you expect to see at adulthood?

as % of total gain between birth and 20 years (~1930s, differential tissue growth), expect to see 100% at adulthood

what is the general growth curve in scammons curve of systemic growth? What is the general shape and what do we usually see changes in?

sigmoidal shape, body mass, skeletal tissue, cardiorespiratory system

is there growth in height represented in the general scammons curve of systemic growth?

shape of general curve matches but values don’t, usually 50% of your adult height by age 2

how does maturation influence the general growth curve?

timing of change (early puberty/maturity-left shift, late puberty/maturity-right shift), rate of change (early puberty is faster), doesnt influence final adult outcome

why is human growth different than animal growth?

duration of childhood growth and rate of adolescent growth spurt (faster) is far greater than other primates

what are the features of human growth?

longest growing primates, delayed somatic growth not brain growth, long period of infant dependency, extended childhood growth period, resurgence of rapid growth at adolescence, followed by sexual and physical activity

what are the advantages of human growth traits?

extended period of brain development, time for: acquisition of survival skills, socialization, play, developing sociocultural skills

what do all children possess in terms of growth?

genetic potential for pattern of growth that is characteristically human

is everything the same throughout human growth in childhood?

tempo and timing at which child passes through stages varies, range in variability of normal growth between children is large

what does growth focus on?

size and shape

what does maturation focus on?

rate of change, progress, and timing

what does development focus on?

quality, refinement, specialization and integration

what are growth, maturation and development influenced by?

genetics (sets limits/potential), environment (sets likelihood of attaining potential), maturity (rarely influences final growth outcomes but determines when you arrive)

why do we want to learn about normal patterns of biological variation at different levels in humans?

once you understand normal patterns you can determine origins, causes and biological significance of variation

how do we see variability between individuals? What do we think about?

which factors explain somatic differences

what is andropause?

drop in testosterone in men

where does growth, maturation and development have their greatest influence in terms of developmental stages?

pediatric

why do ages differ between females and males for later pediatric developmental periods?

initiation of puberty typically ~1 year earlier in females, girls hit peak growth earlier than males

how can you describe growth with the road trip analogy?

total distance (km)

how can you describe maturation with the road trip analogy?

speed or rate (km/hr), timing (when you started driving)

how can you describe development with the road trip analogy?

driving rules

what are some common measures of growth? (growth status)

height and weight for age, BMI for age (weight in kg/height squared in m)

true or false:

skeletal muscle growth during childhood is primarily due to hyperplasia

false

what is growth in skeletal muscle tissue due to during prenatal stages?

hyperplasia primarily

what is growth in skeletal muscle tissue due to during infancy stages?

hyperplasia and hypertrophy

what is growth in skeletal muscle tissue due to during childhood stages?

hypertrophy primarily

what are the general changes in absolute and relative change in mass distribution and segment length throughout growth?

born with larger heads and as you reach adulthood legs grow in length, absolute mass and relative proportions change

does size matter? does body size affect your health or participation in sport or PA?

yes in life and sport

do we always see a relative age effect that favours those born earlier in the year?

no, can see younger athletes favoured (ex:gymnastics and figure skating)