Sometimes a documentary can work like an adrenaline shot, boosting morale and charging the viewer with energy. "Liberty Fields — The Pioneers of Women's Rugby" is such a vehicle.

Even though it's a branded content short film sponsored by Guinness, "Liberty Fields" packs an amazing amount of sincerity and positivity into its 284-second running time, while proffering a small but remarkable window into the little-known world of women's rugby in Japan.

The film tells the story of Liberty Fields, the first women's rugby team in Japan, which formed in the late 1980s, and visits its players in the present day.