To warm up when doing a session with the ball machine, very often I do a first set of around 120 balls in "basic line" mode.
The machine sends:

1. A ball on my forehand
2. A ball in the center
3. A bullet on my back
4. A ball in the center

At an average frequency. I calmly hit the balls and move my legs. No specific objective for this exercise, just to warm up: Warm up.

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