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At puberty, girls gain both fat and lean muscle mass due to theinfluence of female hormones; boys lose body fat and add muscle massdue to the influence of male hormones (Holschen, 2004). Women inadulthood have about ten percent more body fat than do their malecounterparts (Greydanus, D. and Patel, D., 2002, cited in Holschen,2004). The basal metabolic rate is approximately ten percent lower inwomen than in men. The presence of female hormones mandates that womenrely more on fat metabolism at any given exercise level when comparedto men. In addition, glycogen uptake, storage, and use are increased.(Holschen, 2004, citing Bonekat, H. W. et al., 1987; Dombovy, M. L. etal., 1987; Frankovich, R. J. and Lebrun, C. M., 2000; Nicklas, B. J. etal., 1989; Tarnopolsky, L. J., 1990) Cureton and associates (1988,cited in Holschen, 2004) attribute the differences in muscle strengthbetween men and woman to skeletal and cardiac muscular hypertrophy andmuscle mass percentage; they contend that muscle mass in men is fortypercent compared to twenty-three percent in women.

Changes in body composition and circulatory capacity beginning atpuberty result in approximately twenty percent highercardio-respiratory capacity in men. Men also have comparatively higheroxygen-carrying capacity, larger heart and lung mass, a higher strokevolume, and higher maximal cardiac output which result in greatereffectiveness in aerobic and anaerobic activities, although trainingcan overcome the inherent differences (Williford, H. N. et al., 1993,cited in Holschen, 2004).

The results of the current research point to fundamental anatomicaldifferences between men and woman, differences that largely begin toappear during puberty and which have some bearing on runningcapability.

The term running can be defined as [moving] swiftly on foot sothat both feet leave the ground during each stride' (American HeritageDictionary of the English Language, 2000). The research by Bramble andLieberman (2004, cited in Nature, 2004), which was presented earlier,seems to indicate that running has been part of human existence sinceits beginnings and, in fact, contributed significantly to developmentof human life today. Humans no longer require running for survival, atleast in their normal affairs; that is, typically, humans do not haveto run from danger or run in pursuit of animals to kill for food. Inmodern times, running has taken on a new form—competition foot racing.This competition racing can be against oneself to achieve one’s ownpersonal best' or with others. Racing against others can take manyforms ranging from informal competitions between two young friendsracing against one another on a playground to very formal competitionssuch as those in the quadrennial Olympics. The more formal runningcompetitions are typically classified by the length of the run: 100,200, 400, 800, 1500, 5000, and 10000 meters as well as marathons(Dollman, 2003).

There are many terms that refer to specific forms of foot racing: run,dash, sprint, relay, meet, competitive trial of speed, footrace, andmarathon (Webster’s New World Thesaurus, 1997). Of these, the termsdash and sprint are typically used interchangeably to describe ashort, fast r本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。