Should you train with a gi, no gi, or both?
There is no right answer: it really depends on your goals. If your goal is to win many gi sport jiu-jitsu (or judo) tournaments, then you should train with a gi. If your goal is to win many no-gi jiu-jitsu (or submission grappling) tournaments, then you should train without a gi. If your goal is to win both gi and no-gi tournaments, then you should train with both. If your goal is fitness, either or both will keep you fit. If your goal includes self-defense, you should spend a fraction of your time training with a gi. It’s useful knowing how to execute some basic gi techniques (especially collar chokes), but more importantly how to defend against some basic gi techniques (especially collar chokes). From the 10th Planet JJ perspective, the majority of your time should be spent in no-gi training because all no-gi techniques work with or without a gi, but many gi techniques work only with a gi. But the bottom line is that “it depends” on your goals.