If a child is not properly cared for in the beginning of life, so that he doth not develop a sound body and his constitution doth not flourish as it ought, his body will remain feeble, and whatever is done afterward will take little effect. This matter of protecting the health of the child is essential, for sound health leadeth to insights and sense perceptions, and then the child, as he learneth sciences, arts, skills, and the civilities of life, will duly develop his powers…

‘Abdu’l-Bahá, Lights of Guidance, p. 293

Athletics refresh the body, tranquilize and enlighten the mind, and develop moral character. As a concrete example let us take a student in his college activities. The student who does exercise is always fresh and vigorous, he seldom gets sick and tired. His jovial character, his good disposition and his interest in life are his chief characteristics.

Moreover in exercising, the student gets animated, his blood is purified and consequently his mind becomes more apt to receive the ideas and thoughts found in his lessons. The health which he acquires will help him to work harder and he becomes more successful.

A weak person seldom can endure the hardship of school-life, the trouble of memorizing and persevering in his daily lessons. Lastly when a student is busy with athletics during recess time his ideas do not deviate any more to the path of impurity, to think of such trivial things and the health and strength which he acquires will help him in overcoming such temptations. Generally a healthy person is endowed with a will stronger than that of a weak person.

We see therefore that athletics ameliorate the condition of a person during all his college course.

Sports, in general, have had an important and estimable function in life and will inevitably in future be regarded as the indispensable factor for intellectual and moral growth.

Shoghi Effendi, The Students' Union Gazette, pages 28-30 American University of Beirut, 1914-15

Playing games is not in the least forbidden. It should in fact be encouraged if they are of an athletic nature

Shoghi Effendi, Lights of Guidance, p. 294

You should not neglect your health, but consider it the means which enables you to serve. It -- the body -- is like a horse which carries the personality and spirit, and as such should be well cared for so it can do its work!

Shoghi Effendi, Lights of Guidance, p. 297

One of the signs of a decadent society, a sign which is very evident in the world today, is an almost frenetic devotion to pleasure and diversion, an insatiable thirst for amusement, a fanatical devotion to games and sport, a reluctance to treat any matter seriously, and a scornful, derisory attitude towards virtue and solid worth.

The Universal House of Justice, 1997 Jan 12, The Humourist, p. 2-3

He also kept, as far as possible, His daily habit of a walk out of doors.

H.M. Balyuzi, ‘Abdu’l-Bahá -- The Centre of the Covenant, p. 391