3. Train with Free Weights
I still see programs out there that include leg extensions and leg curls. Machines limit your range of motion and control the movement.
Machines can have some limited benefits for beginners, but you need to learn to stabilize and control your body in all three planes of motion simultaneously.
4. Use Multiple Joints
Single joint strength (e.g. leg extension machine, bicep curls) develops strength in the wrong areas. If your strength doesn't transfer to the court, then what's the point of having it?
Machines that isolate have a limited place in the preparation of a tennis player.
5. Train with Explosiveness
Some people feel that explosive moves are dangerous. If you want quick racquet speed and to hit with power, then training explosively is a must because it mimics what happens on court.
6. Train Movements, Not Muscle Groups
Isolated muscle group training (outside of rehabilitation) has no place in your routine. Focus on strengthening specific movements by using your body to work in an integrated fashion.
7. Train Unilaterally and Multi-planar
Most strength training programs train you in one plane (sagittal) with bilateral, or two, movements.
However, the majority of tennis takes place in all three planes simultaneously with many movements. Some 85 percent of the gait cycle (walking, running) is spent with one leg in the air. Most of the shots you play rely on the dominance of one leg.
All your leg training should include exercises such as split squats, step-ups and lunge variations.
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