When we do a ''classic'' preparation, we will first develop the strength, then we will raise the power according to this new strength. This is the most common way (and it works). At the same time, in order to save time in busy seasons and to bring lucidity and always different stimuli (hence the interest of modern physical preparation), we will mix the two, i.e. the development of strength with that of speed/power. This is called "Complex Training". This is also known as contrast training, although it encompasses a bit more. The goal of complex training is to elevate the neuromuscular and psychomotor system on the first exercise and then use it on the second, lighter exercise. A bit like a pre-activation. The particularity of this type of specific training is that we will try to link exercises that use the same muscle chains and the same motor patterns. This book is intended for all those interested in sports training and physical preparation.