11: development of strength and flexibility

Strength

the ability to exert force

Strength training enhanced performance of and

sport skills and activities of daily living

Strength can act as a _ constraint

structural

Weight of muscle mass follows a _ growth pattern

sigmoid

Changes in muscle mass are due to an increase in

fiber diameter

Sex differences in muscle mass and strength are minimal until

puberty

Isotonic strength

exertion of force against constant resistance through the range of motion at a joint

Isokinetic strength

exertion of force against constant limb velocity through the range of motion at a joint

Isometric strength

exertion of force without a change in muscle length

Comparison between individuals requires report of

muscle group, movement type, speed

Strength increases _ as children growth

steadily

____ children are stronger

mature

Why mature children are stronger

improve motor unit activation

Males are generally stronger in the

arms and shoulders

Females produce _% of the force of males

60-80

Cultural norms affect

motivation, habitual physical activity levels

After growth ceases, increase in muscle mass is associated with

resistance training

Strength generally declines gradually after age

40

Decline is strength is generally greater than

loss of muscle mass

Prepubescent children can increase ____ with training without increasing ____

strength, muscle size

Larger relative increase in strength due to training occurs in age

prepubescent

Muscle hypertrophy from strength training doesn’t occur until after

puberty

Change in adult strength with training can be seen in __ weeks

4

Muscle mass can increase by training at _% of max strength

60-85

Strength is stable at age

20

Loss of strength become dramatic at age

50

Flexibility

the ability to move joints through a full range of motion

Optimal flexibility

flexibility which benefits maximal performance at any age, exists within a healthy range

Limited flexibility

flexibility that is the result of sports injuries and restricted mobility, can be due to overlooking for flexibility during training

Why infants and toddlers are very flexible

least solidified skeleton

Flexibility starts to decline during

childhood

Why flexibility declines through development

joints become more stable

Girls tend to participate in activities stressing

flexibility

Sit and reach

assessed flexibility

Changes in female flexibility

yearly, incremental improvements until late adolescence

Changes in mal flexibility

regression during early adolescence followed by rapid improvement

Range of motion probably reflects more than

activity and training, age

Greater declines in flexibility are seen in _ individuals

sedentary

Flexibility training can restore