You need energy to last the day, so aerobic base first, then start with interval training once or twice per week. Aerobic or steady state training is optimal at two sessions per week for 45-55 minutes at a moderate pace. On alternate days, develop your anaerobic threshold using best using 60-90 second interval, 60-90 second recovery. You should repeat that work/rest interval for a full 35-40 minutes before cooling down. Cycling is really good for interval development, second would be total body elliptical or stair machine.
While formal plyometrics or jumping exercises have little benefit before you maximize your strength, you can still start the agility process with activities like volleyball, basketball and racquetball which all have movement-change components. This will allow you to have some fun while letting your body gradually adapt to directional challenges.
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