1. Chapter 15 Adolescent Growth, Puberty, and Reproductive Maturity
© Gallahue, D.L., & Ozmun, J.C.. Understanding Motor Development.
McGraw-Hill

2. Key Concept
The Transition From Childhood to Adolescence Is Marked by a Number of Significant Physical and Cultural Events That, in Combination, Contribute Markedly to Growth and Motor Development

3. Adolescence Defined Biologic considerations (earlier start)
Cultural considerations (later finish)

4. Adolescent Growth
Genotype & Phenotype (genetic & environmental growth potential)
Genotype (biology determines: final body measures, skeletal & sexual maturation, & body type)
Phenotype (growth potential: body weight, skin folds, circumferences)

5. Height Adolescent growth spurt
- Males (average start; Age 11, peak; 13, taper; 15, finish; 18)
- Females (average start; Age 9, peak; 11, taper; 13, finish; 16)
- Peak velocity (average 1 yr. gain 6-8 in (15-20cm)
- Genotype drives height gain (figure 15.1)

6. Height (Cont.) Peak height velocity
- Males (coincides with secondary sex characteristics)
- Females (coincides with secondary characteristics but precedes menarche)
Predicting adult height (table 15.1)
Steroids and stature

7. Weight Peak weight velocity (due to >muscle mass, fat mass & ht.)
- Males (close match with peak ht., Age 10 = 55% of final adult wt.)
- Females (> increase in fat mass, by age 10 = 60% final adult wt.)
- Phenotype drives weight gain (i.e. diet, exercise, lifestyle)

8. Heart and Lungs Heart (size >by ½) - Female resting rate = 62-63bpm
Lungs (size >by ½)
- Respiration rate decreases
- Vital capacity increases, but is much greater for males

9. Pubescence
Puberty: Onset of sexual maturation. (begins with growth spurt & secondary sex characteristics,culminates with reproductive maturity)
- Females (average onset: age 9, early <8, late >13, secular changes)
- Males (average onset: age 11, early <9, late >14, secular changes?)
Culminating event (females = menarche, males = ejaculation)

10. Sexual Maturity
Female menarche (USA average age; 12.5, Blacks; 12.1, Whites; 12.9, Asians; 12.3)
- Early menarche (why? i.e. what is the mechanism)
- Late menarche (why? i.e. what is the mechanism?)
Sequence of puberty (table 15.2)

11. Female Sequence of Puberty
Breast development (table 15.3)
Pubic hair formation (table 15.3)
Rapid height gains
Axillary hair formation
Menarche
Acne

12. Male Sequence of Puberty
Testicular growth (table 15.4)
Pubic hair formation (table 15.4)
Rapid height gains
Axillary hair formation
Facial hair formation
Deepening of voice
Acne

13. Pace of Puberty Pace (earlier onset, but same duration)
What triggers gonadotropic hormones?
- Genotype
- Stress
- Diet & nutrition
- Exercise & percent body fat
- Chronic illness & disease
- Environmental toxins

14. Maturity Assessment Using Tanner stages
- Advantages (valid, reliable, objective)
- Disadvantages (embarrassment, social-cultural mores)
Using subjective clues (height, facial & axillary hair, voice)

15. Concluding Concept
Adolescent, Growth, Maturity, and Sexual Maturation Are Complex Processes Requiring Sensitive, Understanding and Nurturing Adult Support