Actually, it is relative. It depends on the player's physical fitness, physique, physical strength and training proficiency.

Beginners, in general, train three times a week for about 30 minutes each time;

I have mastered the basic movements, basic introduction, training twice a week, 1 time for 45 minutes;

If you master the basic skills, you must train your physical fitness. Weekly training 1 time, about 75 minutes each time;

Those who have certain physical strength and endurance and can stand independently usually play twice a week, such as Wednesday and Saturday, once playing 1-2 hours (one hour for singles and two hours for doubles).

Of course, if you have good physical strength and enough time, you can suggest playing three times a week. Under normal circumstances, twice a week has already had obvious effects. If you can persist for three months, your skills will have unexpected effects.