Conditions of Bones and Muscles at the Period of Puberty
At this time there is also rapid growth and development of the bones which lengthen rapidly, and are still soft and cartilaginous in places. It is all-important at this period, therefore, that the muscles on the two sides of the body receive roughly the same amount of use, otherwise there is grave danger of some deformity, such as lateral curvature of the spine, developing.
While the bones are in this condition of rapid development, all muscle-straining attitudes, such as sitting upright at a desk, practicing at the piano, writing, painting, etc., should be kept within such limits as never to entail real fatigue. Young girls at this period, even more than boys, require all their strength and vitality to support them in their rapid growth. This does not mean, however, that all muscular exercises must be forbidden during the period of puberty, which may be reckoned as from twelve to sixteen in girls, and from thirteen to sixteen in boys. The point is that violent, really fatiguing exercise, such as hockey, hunting, cycling tours, mountain climbing, etc., as well as all occupations which entail the holding of the muscles tense and fixed in one position for a long period, should be indulged in very sparingly, if at all. The young girl can obtain all the exercise necessary for health in less strenuous outdoor pursuits such as golf, croquet, a little not too strenuous tennis, walking, etc.