If you train multiple disciplines, have long days of training (or training-then-working), or simply bring a lot of crap to the gym, you need a bag that isn't going to burst at the seams after a few months. Rather than going through a new bag every year, travel in style and convenience with something built for our sport: the Hayabusa Power Backpack.
Do not let the term "backpack" deceive you. This ain't a school bag that fits a few textbooks. This thing could take you on an excursion across South America (to Rio, of course). You could easily get your Gis (multiple), striking gear, cleaning products, and personal affects into this bag, day in and day out.
There is, of course, a roomy main compartment. But there's also a fleece-lined pocket for more valuable and fragile items such as your phone. The quick-access lid pocket is great for keys, wallet, etc. Throughout the sides, breathable mesh ensures that your bag doesn't suffocate in the heat.
Padded straps and padded back sections add comfort to your trip, while the waist strap clicks around front to lighten the load on your back/shoulders. Easily converts to a duffel style bag as well.