Pre-stretching:
stretching of the muscle generating an accumulation of elastic energy that can be used in the following contraction.

Bosco’s tests:
battery of tests, carried out with specific measurement tools, providing important information of the neuro-muscular capabilities of the subject.

Negative and positive or eccentric and concentric muscular work:
a muscular contraction is defined as negative or eccentric when the generated strength is insufficient to win the load and therefore the muscle is stretched. On the other side a contraction is defined as positive or concentric when the muscle is shortened.

Elastic energy:
is the elastic energy stored in a muscle when it is stretched. This energy can be use during the following contraction.

Volume of training:
is the quantitative aspect of physical training defined as time, duration, covered distance, weights lifted or number of repetitions of an exercise. The notion of volume concerns the total quantity of activity carried out in a training (whether it a single session or many)

Intensity of training:
the intensity of training is the qualitative aspect of training carried out in a specific period of time. The level of intensity has to be carefully monitored according to the type of exercise. If in case of long duration exercise heart rate measurement can be sufficient to measure the level of intensity, in exercise with more muscular involvement there is a need for more sophisticated systems then the number of repetitions or the weight used. In particular these measures don’t provide information on the speed of movement, fundamental aspect to determine power, that in reality is the best indication of intensity in most of the exercises with muscular involvement.

Relationship between volume and intensity:
When an athlete performs physical activity generally both quantitative and qualitative aspects are involved making difficult to differentiate among the two. When an athlete swims, the duration of the exercise is the volume and velocity (represented by the time or by the heart rate) represents the intensity. More or less emphasis on one aspect generates different long and short term effects on the body. Generally there is an inverse relationship between intensity and volume. The longer the exercise the lower the intensity. For this reason objective measurement tools are essential for the planning of a correct physical activity.

Density of training:
is the frequency with which the subject is exposed to the stimulation. This factor is fundamental because it represents the correct relationship between training and recovery. In fact the recovery between two training session depends on the intensity and the volume.

Workload:
the stimulation to which the body is exposed and that guides its adaptation. The workload should be carefully evaluated because aspects such as mental stress can increase the load perceived by the body even when the exercise remains the same.

Periodisation of training: micro-meso and macro-cycles:
planning of training in time that allows to subdivide the work in shorter periods of time, easier to analyse and monitor. Periodisation allows also to break down the objectives in smaller units, easier to reach. Micro-cycle refers to the shortest unit considered for planning. In most cases this is a week. Meso-cycle can be of variable duration, generally around three months and allows the achievement of intermediate objectives. Macro-cycle is also of variable duration but in general a year is taken into account. In special cases, as in Olympic sports, Olympic cycles of four years can be used, bridging the period between one game and the other.