Muscular strength exercises is of such
constant event in daily life, and its more obvious benefits arc so familiar to
everybody, that the complexness of the processes underlying it is apt to be
overlooked. Yet knowledge of the changes taking place in the body during
exercise, and of the adjustments involved in carrying it out efficiently, is of
more than mere academic interest. It is essential, for instance, that the
clinician, who is called upon almost daily to decide whether, and to what
extent, the patients should take muscular strength exercise, should be
acquainted with the effects which muscular activity produces upon the various
organs of the body, and especially with the significance of the circulatory and
respiratory changes associated with it.
Further, the elaborate investigations of
industrial fatigue which have been carried out during the last few years leave
no doubt that not only the efficiency of the worker as a member of the community,
but also his health, and even his entire outlook upon life, are closely bound
up with the conditions under which his manual labor is carried out. A fuller realization
and a more direct practical application, by employers and administrators, of the
physiological principles, which underlie the capacity of the body to perform
muscular work, would undoubtedly greatly improve the health of employee through
muscular strength exercises.
Muscular strength exercises is the highest expression of the activities of the body considered
merely as a machine, and almost all the resources of die body are mobilized in
order to bring about the greatest efficiency of the neuro-muscular system. To a
spectator its most conspicuous features are the wonderful co-ordination of the
muscular movements and the immense power of the body to develop energy,
particularly when these are displayed to perfection, as, for example, in the
gracefulness of an expert dancer or figure-skater, or in the power of a trained
crew rowing in a boat-race. These are rendered possible by the concentration
for the time being of the entire energies of higher nervous centers upon the
actual muscular movement, and the individual, who is engaged in such muscular
strength exercise, is usually conscious of little but the effort he is making,
his whole attention being focused upon the actual physical exertion.
The important part played by the central nervous
system is also seen in the large accession of working power which occurs, when
exercise is performed under the stimulating influence of emotional excitement,
or, conversely, in the lessened efficiency of a man who is not interested in
the work which he Is carrying out. Since muscular strength exercises is as much
a nervous as a muscular process, its beneficial effects are evident in the
psychical as well as the physical life of the individual; and, as the sports
therapist has said: “Even if the day ever dawns in which it will not be needed
for lighting the old heavy battles against nature, muscular
vigour will still always be needed to famish the background of sanity,
serenity, and cheerfulness to life, to give moral elasticity to our
disposition, to round off the wiry edge of our fretfulness, and make us good-humored
and easy of approach through the muscular strength exercises ”. Consequently,
induced movements—useful though they may be—fall far short of voluntary
exercise as a means of maintaining health and vigour.
