Aims of the chapter 30

Introduction 30

Key applications of science to exercise and sport 31

Scientific principles of liquids 31

Pressure in stationary liquids 32

Buoyancy force and Archimedes’ principle 34

Pascal’s principle 36

Pressure in flowing liquids 37

Bernoulli’s principle 40

Solutes, solutions and concentration 40

Hydrogen ions 42

Application of science to exercise and sport 43

Blood pressure 44

Cardiovascular health 47

Self-test 47

Conclusion 48

Key points 48

Bibliography 49

Further reading 50



This chapter is designed to provide an understanding of the scientific principles of liquids which are relevant to the theory which underpins exercise and sport. After reading this chapter, you should be able to:


The term ‘fluid’ can be defined as ‘a substance that flows’, which by definition could include gases as well as liquids. There are many examples of exercise and sport activities taking place in a fluid environment, such as swimming, water aerobics, sailing and trampolining. This chapter will, however, refer to fluids only in the context of liquids (see Chapter 2 for discussion of gases), although there will be times when the laws/principles apply equally to gases. To appreciate the laws and principles as applied to gases it is advisable to read this chapter in conjunction with Chapter 2. In instances whereby laws/principles apply not only to a liquid but also a gas, the text will refer to the dual application.