Girls and boys gain strength during childhood and adolescence. Part of this increase is caused by growth-bigger muscles and longer levers (limbs) generate more force, which translates to greater strength. As children grow, they become more ef¬ficient in the production of movements; this re¬sults in greater strength, as we learned in chapter 3. The nervous system recruits muscles more effi¬ciently, which also increases strength. So, strength increases because of growth, maturation, and practice. At puberty, testosterone levels increase in boys, and as a result, muscle mass increases. So, at around 13, girls gain fat and reach maturity whereas boys gain muscle and continue to grow and mature (Thomas and French 1985). Conse¬quently, muscle strength increases for boys and can be observed in tasks that require strength. Girls and boys are (and should be) similar in strength during childhood, although some tasks have large gender differences. Grip strength, sit-ups, and the vertical jump have small effect sizes until puberty (figure 6.3). Tasks that require up¬per-body strength, such as chin-ups and pull-ups, however, show large gender differences: Girls can do 0 to 1 chin-up and boys can do 1 to 10 chin-ups, on average, during elementary school, as you can see from figure 6.4. Practice is the most likely reason for the differences in these tasks; if girls were expected, encouraged, and practiced, their perfor¬mance would be similar to that of boys. Consider young female gymnasts, who demonstrate upper-body strength; clearly, it is possible for girls to do chin-ups!
Weight training for children is a controversial topic. The two most important issues are cost benefit trade-off and potential for injuries. Weight training takes a lot of time, and for prepubescent children, the gains are small (Faigenbaum, Westott, Loud, and Long 1999). Therefore, the time might be better spent doing something else, such as practicing skill (COPEC 1998). As children are growing, there is risk of injury; training regimens that are low intensity (low weight), however, can be safe (LePostellec 2002). Specific guidelines for prepubescent weight training are available (Kraemer and Fleck 1992). One critical component of weight training for children is involving a teacher or coach who is certified to coach young children (Kraemer and Fleck 1992). Generally, weight training is not a good use of physical edu¬cation time during elementary school.
Most children do well on the sit-up tests, al¬though practice and training are important. Scores often decrease from spring to fall, however, which suggests that practice during physical education improves performance. Girls are more flexible than boys in a comparison of test scores for the sit and reach. Again, practice is the most likely cause of these differences. Flexibility is the easiest compo¬nent of fitness to train and the first to deteriorate when we are inactive. Most of us have experienced a time when movement was restricted and flex¬ibility was significantly reduced.
Muscle strength, muscle endurance, and flexibil¬ity improve with training. While gender differences are observed in these components of fitness, no biological reason for the differences is evident before puberty. Therefore, teachers and parents should encourage and expect boys and girls to practice a variety of activities that will maintain or enhance skill performance, such as sit-ups, sit and reach, and pull-ups
Weight training for children is a controversial topic. The two most important issues are cost benefit trade-off and potential for injuries. Weight training takes a lot of time, and for prepubescent children, the gains are small (Faigenbaum, Westott, Loud, and Long 1999). Therefore, the time might be better spent doing something else, such as practicing skill (COPEC 1998). As children are growing, there is risk of injury; training regimens that are low intensity (low weight), however, can be safe (LePostellec 2002). Specific guidelines for prepubescent weight training are available (Kraemer and Fleck 1992). One critical component of weight training for children is involving a teacher or coach who is certified to coach young children (Kraemer and Fleck 1992). Generally, weight training is not a good use of physical edu¬cation time during elementary school.
Most children do well on the sit-up tests, al¬though practice and training are important. Scores often decrease from spring to fall, however, which suggests that practice during physical education improves performance. Girls are more flexible than boys in a comparison of test scores for the sit and reach. Again, practice is the most likely cause of these differences. Flexibility is the easiest compo¬nent of fitness to train and the first to deteriorate when we are inactive. Most of us have experienced a time when movement was restricted and flex¬ibility was significantly reduced.
Muscle strength, muscle endurance, and flexibil¬ity improve with training. While gender differences are observed in these components of fitness, no biological reason for the differences is evident before puberty. Therefore, teachers and parents should encourage and expect boys and girls to practice a variety of activities that will maintain or enhance skill performance, such as sit-ups, sit and reach, and pull-ups
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