1.3 Anaerobic and aerobic exercise GapFill

When we exercise, we produce energy either aerobically (using oxygen) or  effectivelyanaerobicallyeasilysystematically (without oxygen). The predominant energy system used by the body depends on whether the exercise can be satisfied by oxygen delivery to the working muscle. If the exercise demand is greater than that which can be satisfied by oxygen delivery, the body will work  with EPOCanaerobicallyefficientlywith an oxygen debt. When oxygen can satisfy the demands for energy at the muscles, the body works aerobically.

Aerobic exercise can, therefore, be summarised as:

Activities such as long-distance running are predominantly supported by the aerobic system. This is because long-distance running is  an extremea higha difficulta low-intensity exercise carried out over a long period of time.

In contrast, anaerobic exercise is exercise that is completed without the presence of  oxygenwaterheliummethane and can be summarised simply as:

Note that lactic acid is often a by-product of anaerobic exercise and is associated with the uncomfortable feelings we get during   highopenlowcasual-intensity exercise over a short period of time. Examples of events that predominantly use the anaerobic system are the 100 m sprint and   yogaweightliftingmarathonundemanding competitions. 

Some sports, such as rugby and boxing, use both   aerobichydrophobicEPOCcarbon dioxide debt and anaerobic systems more equally. Boxers require the   aerobiccarbon dioxideEPOCanaerobic system to provide powerful muscle contractions, but also require the   carbon dioxidehydrophobicEPOCaerobic system to last the full 12 rounds without excessive fatigue. Rugby players require the   aerobiccarbon dioxideEPOChydrophobic energy system for jogging into position and lasting the full 80 minutes, but will utilise the   EPOCaerobiccarbon dioxideanaerobic energy system for short bursts in attack and for rucking/mauling.