• Eccentric contraction : when a muscle generates tension whilst lengthening (eg: on the descending phase of a bench-press the load is slowed down by an eccentric contraction of the triceps). This type of contraction can provoke stiffness in people who are not used to this exercise.
  
  
• Energy fields/systems : the three systems which supply the energy used in very short exercises with a high level of intensity/power generated; in medium-length exercises with an average level of intensity/power generated (anaerobic lactic system); in long exercises with a low level of intensity/power generated (aerobic system).
  
  
• Exercise programme : the set of exercises used during one or more sessions. In order to ensure a continuous progression and avoid a stagnation effect caused by the body's familiarisation with the exercises used, the exercise programme should be modified every 6 to 8 sessions.