Arguably, there are a lot of bizarre sports played around the world, many of which have caused casual observers to wonder -- is that really a sport?

Some competitions feature opponents battling it out through rousing rounds of rocks, paper, scissor. Others display contestants shoveling as many hot dogs in their mouth as they possibly can in a short period of time.

And then there are these unusual sports -- competitions that feature both boxing and chess, stacking cups, snorkeling through muddy water, chasing a wheel of cheese down a hill, and even racing with your wife on your back.

Chess Boxing

A mixture of knowledge and knockouts, chess boxing features two opponents playing alternating rounds of boxing and chess. In a match, competitors endure six four-minute rounds of speed chess and five three-minute rounds of boxing with one-minute breaks in between. The winner is determined by knockout or referee decision in the boxing rounds, or checkmate or exceeding the time limit in chess.

Located in Berlin, the World Chess Boxing Organization goes by the slogan of: "Fighting is done in the ring and wars are waged on the board."

According to Time Magazine, the chess boxing league formed in Europe independently from the Hip-Hop Chess Federation in the U.S. Founded by Adisa Banjoko and Leo "Blast" Libiran, the HHCF uses "chess, music and martial arts to promote unity, strategy and non-violence."

Wife Carrying

Originating from Finland, wife carrying started as a joke that was reminiscent of an old Finnish custom of when men ran into a village, picked up a woman and carried them off. The joke turned into a sport that is now competed world wide, and even has its own category in the Guinness Book of Records.

In the sport, men race against each other while carrying a woman (she doesn't have to actually be his wife). They work their way through an obstacle course, trying to finish in the shortest time.

Females may hold onto the man using a variety of holds, which include piggy-back, over-the-shoulder, or with the woman hanging upside-down with her legs wrapped around her teammate's shoulders.

Cheese Chasing

A European tradition, cheese chasing combines agility and speed -- all in the quest for a wheel of cheese.

Each May a festival is held in the United Kingdom, where participants flock to Cooper's Hill in Gloucestershire for four cheese-chasing races.

Contestants wait atop the steep, slippery hill while an 8-pound wheel of cheese is given a head start and rolled down the hill. After receiving the go-ahead to begin, the participants maneuver their way down the incline in pursuit of the wheel, often sustaining injuries. The first one to claim the cheese is the winner.

Sport Stacking

Sometimes referred to as "cup stacking," sport stacking is an individual and team sport where participants stack and un-stack 12 specially designed plastic cups in a predetermined order.

The unique sport that can be played by children and adults even has a governing body, the World Sports Stacking Association, which promotes the slogan, "We build only positive pyramids."

Competitors, called stackers, are timed using a special StackMat, and can cause "fumbles" during the event if cups fall while the participant is building the sequence.

Bog Snorkeling

In bog snorkeling, competitors travel two lengths of a 60-yard water-filled trench that's cut into a peat bog in the shortest time possible.

Participants must wear flippers and snorkels, and cannot use any conventional swimming strokes to complete the race.

The sport even has a world championship, which is held each year in Wales.