Nutrition for Sport, Exercise and Performance

A practical guide for students, sports enthusiasts and professionals

Regina Belski, Regina Belski, Adrienne Forsyth, Evangeline Mantzioris

• Publisher: Routledge
• Year: 2020
• ISBN:
  9781000246674
• Edition: 1
• Topic: Medicina
• Subtopic: Salud general

Nutrition before, during and after training or a sporting event can improve the comfort, energy and performance of athletes of all levels, from elite to recreational, as well as providing long-term health benefits. Nutrition for Sport, Exercise and Performance offers a clear, practical and accessible guide to the fundamentals of sport and exercise nutrition. The expert authors begin by explaining key principles, including understanding energy systems, exercise physiology and metabolism. They cover the basics of digestion, absorption and nutrition; examine the key macronutrients and micronutrients essential for performance; and discuss the process of dietary assessment. Part 2 goes on to explore in detail nutrition for pre- and post-training, hydration, the use of supplements and body composition, and provides guidance on developing plans for both individual athletes and teams. The final component examines specific nutrition issues and special needs, including working with elite athletes, strength-and-power athletes, young, older and disabled athletes, endurance sports, GI disturbances and rehabilitation issues. Cultural issues are also explored, including diets for vegan and vegetarian athletes, and religious perspectives and requirements. Featuring contributions from a range of sport and exercise nutrition professionals and including practical diet plans, diagrams and the latest research and evidence throughout, this is a core reference for undergraduates, nutritionists and trainers.

PART 1
THE SCIENCE OF NUTRITION AND SPORT

Chapter 1

Introduction to sport and exercise

Kane Middleton, Andrew Govus, Anthea Clarke and Adrienne Forsyth

You may be reading this book because you are an athlete, you work with athletes, or you would like to work with athletes in the future. To provide appropriate nutrition advice to athletes, it is important that you understand the practical and physiological impacts of physical activity, exercise and sport. This chapter will provide you with an overview of key concepts related to sport, exercise and performance, and outline the body’s responses and adaptations to exercise.

LEARNING OUTCOMES

Upon completion of this chapter you will be able to:

• compare and contrast physical activity, exercise and sport
• describe different types of sport and exercise, and relate these to differing physiological processes and adaptations
• measure exercise performance and intensity
• describe the principles of exercise prescription
• describe muscle types and actions
• explain the body’s physiological response and chronic adaptations to exercise
• outline how the body recovers from exercise.

PHYSICAL ACTIVITY, EXERCISE AND SPORT

Although often used interchangeably, there is a distinct conceptual difference between physical activity, exercise and sport. Physical activity is any movement that we perform that expends energy. The simplest categorisation of physical activity is based on proportioning activities in daily life—namely, sleep, work and leisure. The energy expenditure during sleep is obviously very small, whereas the energy expenditure during work would depend on the type of employment. A nurse who spends a lot of time walking around a hospital ward would expend much more energy than an office worker who spends the majority of the work day sitting down. In regard to leisure time physical activity, humans typically perform this incidentally (such as walking to the shops), in the household (such as gardening), or during exercise and sport.

Physical activity

Any bodily movement produced by skeletal muscles that results in energy expenditure.

Exercise

Physical activity that is planned, structured, repetitive and purposeful with the aim to improve or maintain one or more components of physical fitness.

Exercise is a subcategory of physical activity. Although it still includes body movements that result in energy expenditure, it is different to physical activity in that it is planned, structured and repetitive. The purpose of exercise is to improve or maintain components of physical fitness, including:

• aerobic and anaerobic capacity (described later in this chapter)
• muscular endurance, strength and power
• body composition (see Chapter 13)
• flexibility
• balance.

Aerobic capacity

The ability of the body to take in and distribute oxygen to the working muscles during exercise.

Accredited Exercise Scientist

A specialist in the assessment, design and delivery of exercise and physical activity programs (Exercise and Sports Science Australia 2018).

Examples of structured exercise include a running program to promote fat loss and/or increase aerobic capacity, a conditioning program to increase muscular strength or a stretching program to increase joint flexibility. If we take the example of a conditioning program, for it to be most effective it would be planned before beginning, ideally by an Accredited Exercise Scientist. The plan would incorporate purposeful exercise and progress the exerciser through mental stages of readiness to change (see Chapter 8 for the transtheoretical model of change). The program would be delivered in a structured, repetitive manner, taking into account the concepts of periodisation and progressive overload (this is discussed in more detail later in this chapter under Chronic Adaptations to Exercise).

It has been difficult to develop a universally approved definition of sport. Currently, the most accepted definition is that of the Global Association of International Sports Federations, which states that the following criteria must be met in order for a sport to become a member of the Association (Global Association of International Sports Federations 2012):

• The sport proposed should include an element of competition.
• The sport should not rely on any element of ‘luck’ specifically integrated into the sport.
• The sport should not be judged to pose an undue risk to the health and safety of its athletes or participants.
• The sport proposed should in no way be harmful to any living creature.
• The sport should not rely on equipment that is provided by a single supplier.

Sport

‘A human activity capable of achieving a result requiring physical exertion and/or physical skill which, by its nature and organisation, is competitive and is generally accepted as being a sport’ (Australian Sports Commission 2018).

In Australia, the Australian Sports Commission currently (at time of print) recognises 95 national sporting organisations. Their definition of sport focuses more on physical effort and skill that includes a competitive element.

TYPES OF SPORT

Due to the large variety of sports in existence, the Global Association of International Sports Federations has also developed categories of sports. These categories are based on the primary (not exclusive) type of activities that make up the sport. The list of categories and examples of sports in those categories can be found in Table 1.1. Note that many sports may belong to multiple categories.

Table 1.1. Categories of sport

Category	Examples of sports
Physical	Football, Basketball, Athletics
Mind	Chess, Draughts, eSports
Motori sed	Formula One, Motorcycling
Coordination	Lawn Bowls, Billiards, Shooting
Animal-supported	Horse Racing, Equestrian, Polo

Primarily physical sports are by far the most common and best known, and it could be strongly argued that nutrition is more important in these types of sports. Whether a sport is individual or team-based, the physical requirements of that sport will lie somewhere on an endurance–power continuum (Figure 1.1). Sports such as marathon running and tria...