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LTPD Pathway
Functional Screening
Anatomical Adaptation
Game Demands
Conditioning for Rugby
Periodisation in Rugby

The demands of the game

The energy systems

Before describing and discussing the physical demands of the game of Rugby, it is important to appreciate, at a basic level, the energy systems used in the game. There are three energy systems that the body uses to derive energy for work:

  1. The primary (ATP-CP) system
  2. The secondary (anaerobic) system
  3. The tertiary (aerobic) system

In reality, all three systems play a part in supplying the energy to the player to meet the demands of the game. To simplify our understanding of the energy systems we will use general athletic examples. The marathon runner, for instance, relies heavily on the aerobic system to supply energy, as the race is a continuous unbroken event lasting more than 2 hours. The 400m runner relies heavily on the anaerobic system during an all-out run that typically lasts for between 45 seconds and 60 seconds. The 100m sprinter will rely heavily on the ATP-CP system because this system provides energy at a very high rate, even though its supply is very limited.

As noted, the game of Rugby challenges all three systems. However, as the game involves repeated high intensity efforts, we can conclude that the primary and secondary systems will be relied on heavily by players when contact and intense activities take place. Also, the aerobic system plays an important role in recovery from these high intensity bouts.

It is possible to estimate the contribution of the three energy systems to match play. For example, Docherty and colleagues (1988) noted during video analysis of amateur club and international fixtures that typically a duration of between 5% and 10% of a match was spent performing high intensity work. The authors noted that the Primary energy system would be the dominant contributor to high intensity work. Even though the relative percentage of match play spent in high intensity efforts may seem low, these are the important and significant bouts of play in the game. Further, today’s game is more demanding in terms of high intensity work and so there will be a greater challenge to the Primary and indeed the Secondary energy systems (Bloomfield, 2007, Deutsch et al, 2006).