Each phase has different objectives and each successive phase builds on the previous one. This is called periodization.
How Periodized Programs Work
Unlike football or baseball, you can pretty much play tennis all year round—indoor or outdoor.
This is how a weight training program might look if your tennis playing season is followed by a closed or ‘off’ season and you need to build up and then take some time off.
Early Pre-Season
During the early pre-season time, players are preparing for the season and starting to build up after taking a break. Here, the emphasis is on building functional strength and some muscle bulk (hypertrophy).
Late Pre-Season
In late pre-season, players are working up to the start of the season. At this time, the emphasis is on building maximum power.
In Season
Break Season
Now it’s time to relax for a while. However, you need to keep active if you want to maintain some level of fitness for the next season. Instead, the emphasis is on rest and recovery with maintenance of light activity, such as cross training and light gym work.