After the success of the 2012 Olympic Games, London is currently hosting the World Athletics Championships. To join in the excitement, we bring you a selection of athletics-related articles, a puzzle, and a little something on the spread of infectious diseases. Enjoy!

No limits for Usain

People keep running faster and faster. But is there a limit to how fast the 100m can possibly be run? A limit that applies not only to Usain Bolt, but to all top athletes of the future? This article explores the question.

Runnin' in the wind

Runners can tolerate heat and cold but the thing they dislike most is wind. They know it produces slower times. Can we show them why?

The maths of gold medals

Sport may bring out the best in us humans, but at the end of the competition all the attention is on the cold hard facts of the medal table. This article explores the maths of gold. It was written for the 2012 Olympics, but much of it applies to the current championships too.

The logic of drug testing

Sadly, doping is a serious issue in athletics. But when an athlete fails a drug test can we really conclude that they are cheating? This article does the maths.

The mathematics of diseases

Catching a nasty bug when you are competing in the world championships is a real bummer. Maths can't prevent such freak accidents, but it can help us understand how those evil viruses spread.

And as promised, here is a puzzle:

Suppose the competition has ended and the medal table is complete. Given the following clues, can you work out the number of gold, silver and bronze medals that France, Italy and Japan got?

- Japan has 1 more gold medal, but 3 fewer silver medals, than Italy.
- France has the most bronze medals (18), but fewest gold medals (7).
- Each country has at least 6 medals of each type.
- Italy has 27 medals in total.
- Italy has 2 more bronze medals than gold medals.
- The three countries have 38 bronze medals in total.
- France has twice as many silver medals as Italy has gold medals.

*This brain teaser comes from our sister site NRICH.*