Running, gym, city - why is your old backpack falling behind?

If you run, you know that "lightness" is a key word. But lightness doesn't have to mean flimsiness. Big sports backpacks are great for a trip to the Tatras, but for a quick workout after work?
That's like using a sledgehammer to crack a nut.

A gym sack is a synonym for freedom. You throw in your shoes, water bottle, a change of t-shirt and you're off.
But the devil is in the details. 

Cords that don't torture. Thick, substantial cords are essential. If you've ever come back from a workout with red marks on your shoulders, you know what I'm talking about. Here you have a locking clasp – it's a small gadget that prevents the bag from "dancing" on your back when you pick up the pace.

No more "black hole." An independent internal pocket and a carabiner for keys are an absolute game-changer for me. Keys clipped close at hand, phone in a separate compartment, won't get scratched by a zipper or shoes. Simple? Simple. And how much it simplifies life!

Material that doesn't tear. 300D polyester is serious stuff. It won't wear out after a month of being tossed onto a bench in the locker room or on the grass in the park.