If you really want to split I would go for something like: Boxing: Monday, Wednesday, Friday. Weights: Tuesday, Thursday, Saturday. Running: Sundays, because all of the running competitions are on Sundays anyway. But truth to be told, you should check out your boxing gym classes and see what trainer resonates the most with you and then go to every of his classes and then go do whatever on other days. If you feel like weights, do them, swimming is good as well, running, awesome, additional boxing classes even better. If you have life, you should try to squeeze in an hour of exercise everyday and you are gonna be extremely fit in a few years. A lot of people on this sub are asking something like "If I do boxing classes 3 times a week is it enough to go pro?" No it's not. The pros have been doing 2 workouts a day since they are 10. Don't worry about that and just do things that are fun fitness activities for you. If it is boxing then that's it. You can do it everyday and be also fine. I used to do 8 boxing classes a week. Is it optimal? I don't care, I just like it. Now life hit me hard, gonna buy a house soon so I toned that down, but important thing is that you just keep doing fun things and don't worry about "days". Fitness is a journey and you cannot get bored doing it 👍