In order to better address the needs of our fitness-obsessed readers, we are introducing this semi-regular column, "I of the Tiger," to take on the vital hardcore fitness issues of our time. Today: girl stuff. Dig it.

In this world, there are many ways to exercise. Some are actual sports; others are specific types of exercise; all will make you sweat, somehow. We have ranked them in scientific order, based on the following criteria: Physical Difficulty; Amount That You Would Be Humiliated If You Tried to Just Waltz In and Do Them…

Australian fitness class participants: are they listening to pop music authentic enough to get them pumped? Alas, the answer may be "no." Because in Australia—whether it's cardio-kickboxing, spinning, or some other bullshit—it's set to Britney cover tunes.

All the world government big shots are meeting in London tomorrow for the G20. Really, they're much more worried about the hardtothemuthafuckincore protesters than the economy thing. Are UK protesters putting American protesters to shame?