Option B5: Fitness and training

What is fitness? Fitness is the ability to undertake specific

activities without excessive fatigue.

What are the properties of slow-twitch fibres and fast-

twitch fibres? Fast-twitch muscle fibres

generate high force for a short time.

Fast-twitch fibres rely on the glycolysis/lactate energy system (anaerobic energy source)

Slow-twitch muscle fibres achieve less force but sustain it for a longer time

Slow-twitch muscle fibres have an aerobic energy source.

Fast-twitch fibres Quality Slow-twitch fibres

contract quickly speed of contraction contract slowly

glycolysis/lactate pathway. anaerobic

energy source aerobic respiration pathway sited in the many mitochondria

little dependence on oxygen for fast

contraction – little myoglobin present (light

in color)

dependence on oxygen supply

highly dependent – well endowed with myoglobin oxygen store (so red in color)

can contract with great force, but power quickly

exhausted

power and duration of contraction

can contract repeatedly but with limited power

sprint runners typically have 80% of these fibres

in some skeletal muscles

occurrence marathon runners typically have 80% of these fibres in some skeletal muscles

Speed and Stamina Stamina is the ability to endure

prolonged physical or mental strain.

Speed is another important factor of fitness for an athlete. Speed is the rate that someone moves over a given distance.

Training programmes devised to achieve fitness must relate to the particular sporting activity and the muscle-fibre type and the dominant energy transfer system.

Ethics of performance-enhancing substances

Performance enhancement refers to: The use of certain substances which may have the effect of improving artificially an athlete’s performance: these might act directly on muscles, nerves, blood circulation or breathing, or indirectly, via their effects on mental state.

The naturally occurring sex hormones testosterone and oestrogen are chemicals known as steroids, and are manufactured in our bodies from cholesterol

Anabolism is the building of large molecules, such as proteins, including muscle protein.

For Against• allows for exceptional

development of skeletal muscles, it can help a genetically-disadvantaged athlete

• not fair competition; the user is cheating / being immoral. the process is also unnatural

• enable competitors to train harder because it allows injured athletes to recover faster

• serious negative side-effects + risking life (e.g. high doses of anabolic steroids can cause liver disease)

• increase aggression and competitiveness

• dangerous role model for young fans

• readily obtained, and if use is monitored, health risks can be avoided

• drug development should focus on disease prevention and cure

• suppress fears of not ‘making it’, given the high expectations of peers, press, etc.

• gives technologically and economically developed countries an unfair advantage

• provide employment and economic benefit by opening up a new market

• as currently illegal, criminal organizations are profiting