Core 2: Factors affecting performance
How does training affect performance?

When athletes train they are trying to improve the way their bodies function and perform. There are many similarities in the way training programs are designed and the principles that guide their design. To understand how training affects performance it is important to have a knowledge and understanding of the energy systems, types of training  and training methods, principles of training and physiological adaptations in response to training.

Energy systems
The human body requires a continuous supply of energy both to meet the metabolic needs and to power muscular contraction for movement. There are three energy systems which provide the working muscles with energy for movement. These include:

    * the two energy systems which operate without the presence of oxygen - the alactacid (ATP/PC) system and the lactic acid system
    * the energy system that operates with oxygen - the aerobic system.

The predominance of any system or systems during activity is dependent on the duration and intensity of the activity.

Types of training and training methods
The type of training carried out by an athlete should target the specific needs of the activity being trained for. Training programs can focus on different aspects of fitness and can include aerobic, anaerobic, strength and flexibility training. Aerobic training aims to improve the ability of the body to use oxygen. Anaerobic training focuses on developing the ability of the body to recover from brief intense activity. Strength training focuses on the ability of the muscle to produce force. Flexibility training works to improve the range of movement at a joint. All types of training play an important role in improving performance.

Principles of training
Training programs need to challenge athletes physically if the aim is to improve performance. The principles of training guide the athletes about what will work to produce a training effect. These include progressive overload, specificity, reversibility, variety, training thresholds and warm-up and cool-down. It is also important to understand how these principles relate to each type of training.

Physiological adaptations in response to training
While training will cause immediate physiological responses in the body, athletes are looking for adaptations and long term responses to improve performance. These adaptations allow the athlete to achieve higher levels of work. They include changes to resting heart rate, stroke volume and cardiac and cardiac output, oxygen uptake and lung capacity, haemoglobin level, muscle hypertrophy, and effects on fast/slow twitch muscle fibres.