Introduction to Sports Biomechanics: Analysing Human Movement ...

INTRODUCTION TO SPORTS BIOMECHANICS
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SUMMARY
protocol or period of testing, it has been suggested that 30–50 repetitions or a total
duration of 30–60 s should be used. The fatigue index can then be expressed as the ratio
of the maximum torques recorded in the initial and final periods of the test.
In this chapter, we focused on the anatomical principles that relate to movement in
sport and exercise. This included consideration of the planes and axes of movement and
the principal movements in those planes. The functions of the skeleton, the types of
bone, the process of bone fracture and typical surface features of bone were covered. We
then looked at the tissue structures involved in the joints of the body, joint stability and
mobility and the identification of the features and classes of synovial joints. The features
and structure of skeletal muscles were considered along with the ways in which muscles
are structurally and functionally classified, the types and mechanics of muscular
contraction, how tension is produced in muscle and how the total force exerted by
a muscle can be resolved into components depending on the angle of pull. The use of
electromyography in the study of muscle activity in sports biomechanics was considered,
including the equipment and methods used, and the processing of EMG data.
Consideration was given to why the EMG is important in sports biomechanics and why
the recorded EMG differs from the physiological EMG. We saw that electromyography
shows us when a muscle is active but not, in complex multi-joint sports movements,
what the muscle does. We covered the relevant recommendations of SENIAM and the
equipment used in recording the EMG along with the main characteristics of an EMG
amplifier. The processing of the raw EMG signal was considered in terms of its time
domain descriptors and the EMG power spectrum and the measures used to define it.
We concluded by examining how isokinetic dynamometry can be used to record the net
muscle torque at a joint.
STUDY TASKS
Many of the following tasks can be attempted simply after reading the chapter. For
some of the following study tasks, a skeleton, or a good picture of one, is helpful,
while ones involving movements will require you to observe yourself or a partner.
These observations will be easier if your experimental partner is dressed only in
swimwear. If you are observing yourself, a mirror will be required.
1 With your experimental partner, perform the following activities for each of these
synovial joints – the shoulder, the elbow, the radioulnar joints of the forearm,
the wrist, the thumb carpometacarpal joint, the metacarpophalangeal and interphalangeal
joints of the thumb and fingers, the hip, the knee, the ankle, the subtalar
joint (rear foot), and the metatarsophalangeal and interphalangeal joints of the toes.