Bukatsu refers to after school clubs Japan. Practice here is more frequent than in Canada. At my school, all teams have practice from Tuesday to Friday before and after school. There is practice on Saturday mornings, too. It usually ends just before noon.
I’ve felt practice is less about winning or becoming the best. It’s more about having a place to socialize and have fun with friends (while practicing a sport).
Seniors don’t attend practice during the second and third terms because they should be studying for high school or university entrance exams. When you factor in all the time at school, club activities, and juku, it’s easy to understand why Japanese kids always say they’re tired.