Enquire within upon everything

1745. Three Principal Points. Three principal points in the manner of taking exercise should be attended to: i. The kind of exercise. ii. The proper time for exercise, iii. The duration of it. With respect to the kinds of exercise, the various species of it may be divided into active and passive. Among the first, which admit of being considerably diversified, may be enumerated walking, running, leaping, swimming, riding, fencing, different sorts of athletic games, &c. Among the latter, or passive kinds of exercise may be comprised riding in a carriage, sailing, friction, swinging &c. 1746. Active Exercises. Active exercises are more beneficial to youth, to the middle-aged, to the robust in general, and particularly to the corpulent and the plethoric. 1747. Passive Exercises. Passive kinds of exercise, on the contrary, are better calculated for children; old, thin, and emaciated persons of a delicate and debilitated constitution; and particularly for the asthmatic and consumptive. 1748. Time. The time at which exercise is most proper depends on such a variety of concurrent circumstances, that it does not admit of being regulated by any general rules, and must therefore be collected from the observations made on the effects of air, food, drink, &c. 1749. Duration. With respect to the duration of exercise, there are other particulars, relative to a greater or less degree of fatigue attending the different species, and utility of it in certain states of the mind and body, which must determine this consideration as well as the preceding. 1750. Accustomed Exercise.