Serious training is planned in phases rather than repeated week after week. The reason is that the body adapts to a stimulus and then stops responding to it.
Adaptation is a response to change
Training works by disturbing the body enough that it rebuilds slightly stronger. Once a given workload stops being disruptive, the rebuilding stops with it.
Simply adding more of the same eventually produces fatigue faster than adaptation, because recovery capacity is finite while workload is not.
Periodisation manages this by changing what is being asked of the body at intervals, so that each phase presents a genuinely new demand.
Blocks are ordered by what they build on
General preparation comes first and develops the capacities that everything else rests on: aerobic base, tendon and connective tissue tolerance, and basic strength.
Specific preparation follows, converting that base into the qualities the sport actually requires, such as repeated sprints, change of direction or throwing power.
The order matters because power built on an insufficient base is fragile, and the tissue that fails under high-speed load takes far longer to develop than the muscle around it.
Volume and intensity trade against each other
Early phases carry high volume at moderate intensity, which accumulates work without demanding maximal output.
As competition approaches, volume falls and intensity rises, so sessions become shorter and sharper while total weekly load declines.
Attempting both at once is the most common error in self-directed training, and it produces the pattern of rapid early progress followed by stagnation and injury.
Tapering reveals what was built
Fitness gained through training is masked by the fatigue that produced it, so an athlete at the end of a heavy block performs below his actual capacity.
Reducing load before competition allows fatigue to dissipate faster than fitness declines, which is why performance rises during a period of easier training.
The taper does not create anything. It uncovers work already done, which is why it cannot rescue a poorly planned year.
Why team sports complicate the model
The classical structure assumes a single competition to peak for, which suits an athletics season or a championship attempt.
A team playing weekly for months has no such target, so training is organised around the match calendar with load distributed between fixtures instead.
Anyone building a personal plan around a specific event should work with a qualified coach, since load tolerance varies widely between individuals and history matters more than any template.