Humans are capable of performing amazing feats. Sprinters run down the track with astonishing speed and power; power lifters make hundreds of kilograms look like a sack of potatoes; swimmers traverse an entire lake or channel against the elements; hurdlers gracefully clear all obstacles in their way; and some basketball players even seem to defy the laws of gravity. Before muscles can produce movement by pulling on their attachments to bones, they must first obtain a source of energy to sustain such a movement. A complex series of metabolic pathways are present in human muscle that break down substrates from nutritional sources to produce energy for different types of muscular activity. However, depending on the activity in which an individual is engaged, the body will make use of different energy systems that have been adapted for the particular activity (see Figure 1) (1). More specifically, utilization of bioenergetic substrates depends on the type, intensity, and duration of the exercise (2). The aerobic oxidative system is used for longer duration activities of low to moderate intensity, the anaerobic glycolytic system is used for short to moderate duration activities of higher intensity, and the high energy phosphagen system is used for short duration activities of high intensity. The efficiency and effectiveness of these pathways can be enhanced through physical activity and training. It is these bioenergetic pathways that are the focus of this lecture.

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What do athletes competing in the following sports have in common? Swimming, rowing, synchronized swimming, shot putting, tennis, karate, archery, discus, weight lifting, paddling, shooting and many others.

The simple answer is that, like all of us, they must breathe. However, in the case of these, and other athletes, the process of breathing is often intricately inter-twined in the activity, and in fact, the ability to breathe properly and/or to control the activity of breathing in a prescribed manner may well play a major role in their success. The following describes the functioning and limitations of the respiratory system as it pertains to exercise, and suggests a means of training the respiratory system outside of regular training.
This lecture presents the adaptations within the respiratory system to various types of training. Specific respiratory muscle training and endurance training are presented in this lecture.

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Text and pictures are from Wells and Norris 2009. Pediatric Respiratory Reviews. Assessment of Physiological Capacities of Elite Athletes & Respiratory Limitations to Exercise Performance. Copyright 2009.

Physiological assessment of athletes is an important process for the characterization of the athlete, monitoring progress and the trained state or ‘level of preparedness’ of an athlete, as well as aiding the process of training program design. Interestingly, the majority of physiological assessments performed on athletes can also be performed on children with disease, and therefore clinicians can learn a great deal about physiology and assessment of patient populations through the examination of the physiological responses of elite athletes. This lecture demonstrated a typical physiological responses of an elite athlete to a tests of aerobic metabolism.

Physiological Assessment of Aerobic Oxidative Capacity

The overall capability of the aerobic oxidative system is generally evaluated by measuring the maximal volume of oxygen

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