Howcast - Learn how to do the top three plyometric exercises that improve vertical jump in this Howcast workout video about plyometric exercises.

Howcast - Learn how to attack an assailant's groin in this self-defense video from Howcast.

Howcast - Learn how to pinch an attacker effectively in this self-defense video from Howcast.

Howcast - Learn how to do a palm strike in this self-defense video from Howcast.

Howcast - Learn how to do a chin jab in this self-defense video from Howcast.

Howcast - Learn how to punch in this Howcast self-defense video.

Howcast - Learn how to use the tone bar on a pedal steel guitar in this Howcast video.

Howcast - Learn how to swim faster in this swimming lesson from Howcast.

Howcast - Learn how to hula hoop faster from hula hooping expert Natalie "McFancy" Wise in this Howcast video.

Howcast - Learn how to hula hoop around your knees from hula hooping expert Natalie "McFancy" Wise in this Howcast video.

Howcast - Learn how to get out of a hula hoop vortex from hula hooping expert Natalie "McFancy" Wise in this Howcast video.

Howcast - Learn hula hooping basics from hooping expert Natalie "McFancy" Wise in this Howcast video.

Howcast - Learn how to hula hoop around your neck from hula hooping expert Natalie "McFancy" Wise in this Howcast video.

Howcast - Learn how to do a top triangle from scarf hold crucifix MMA submission from Team Radical MMA head coach Rene Dreifuss in this Howcast video.

Howcast - Learn how to do an arm bar from guard MMA submission using high guard from Team Radical MMA head coach Rene Dreifuss in this Howcast video.

Howcast - Learn how to do an arm bar from mount MMA submission from Team Radical MMA head coach Rene Dreifuss in this Howcast video.

Howcast - Learn how to do scissors on roller skates from former World Champion speed skater Gypsy Lucas in this Howcast video.

Howcast - Learn how to t-stop on roller skates from former World Champion speed skater Gypsy Lucas in this Howcast video.

Howcast - Learn how to skate backwards fast on roller skates from former World Champion speed skater Gypsy Lucas in this Howcast video.

Howcast - Learn three tips on how to skate fast on roller skates from former World Champion speed skater Gypsy Lucas in this Howcast video.

Howcast - Learn which cameras are best for portrait photography from professional photographer Joe Sinnott in this Howcast photography tutorial.

Howcast - Learn if you are a goofy skater or a regular skater from competitive skateboarder Nate Cohen in this Howcast skateboarding video.

Howcast - Integrate some simple practices into your training routine; and whether your goal is to run your first 5K, place in track, or improve your personal best, you'll be on the road to running faster.

Howcast -Learn if it's safe to get a head massage when you're pregnant in this Howcast video featuring massage therapist Judie Rhed Yim.