The week's top five most popular sporting trends on March 24 as selected by include a remarkable design for a new Brazilian landmark and a form of two-wheeled transportation that's not so much the devil's horse as it is Death's bicycle.

1) Stunning waterfall structures
The 2016 Olympic Games in Rio have already had a rather special piece of architecture designed for them by the Swiss firm RAFAA Architecture & Design. During the day, it absorbs energy via a large bank of solar panels leading to its entrance, and at night is intended to power lights for the tower or divert electricity to the city. A bungee-jumping platform is placed three quarters of the way up the tower which rises 105m above sea level, and it can produce a waterfall that runs all the way from the top floor balcony back into the Baía de Guanabara.

2) Water bottle cycles
This gallery of unusually two-wheeled pedal transports starts off with a DIY pontoon made by attaching eight office water cooler bottles to a commuter bicycle, and re-engineering its back wheel to contain twelve paddles to propel the cyclist across a body of water.

3) Skeleton Clad Cycles
Vancouver-based artist Eric Tryon integrated a human skeleton into this hybrid commuter bicycle, mimicking the pose of race riders except for the fact that from its skull protrude the cycle's handlebars, the arms turn when rounding a corner, and its feet are attached to the bike's back wheel, moving in motion as the pedals turn.

4) Stylish Skull Shields
Skeletal caps rear their head again in this gallery that shows off a new design from German designer Stefan Wallman. Like BMX and mountain biking helmets, these pieces of protective headwear cover both the top and the back of the skull, but they remain small, stylish, and allow a cooling airflow to pass discreetly from front to back.

5) Surfboards With Handlebars
The Sea Scooter is a curious cross of a surfboard and a jetski. The designer, Kwan Ken Yong, has already won the Red Dot Design Award for his concept that safely stows a small and powerful motor underneath a miniature plastic surfboard, allowing a wave riding experience on gentler waters. Handlebars protrude from the front, like a child's scooter, for enhanced balance and accessibility.