6 big things to know about the track and field world championships

From Canada's top medal contenders to the first men's 100 metres of the post-Bolt era to Caster Semenya's absence to the insane heat in Doha, here are some key points to get you ready for the biggest meet of the year.

The heat is on (literally) at the first worlds post-Bolt

Decathlete Damian Warner is one of Canada's medal contenders in Doha, where it'll feel like more than 50 degrees Celsius with the humidity. (Patrick Smith/Getty Images/File)

The track and field world championships start Friday in Doha, Qatar and run through Oct. 6. The event is held every two years, but this one takes on extra importance with the Tokyo Olympics only 10 months away. Here are some big-picture things you should know about the biggest meet of the year:

It's the first world championships P.B. (Post Bolt)

The sprinting god went out with a thud at the 2017 worlds in London. He finished third in his final 100-metre race and then went down with an injury during the anchor leg of the 4x100 final. If you throw out his DQ for a false start in the 100-m final at the 2011 worlds, these were Bolt's first defeats in an Olympic or world championship race since he took the sport by storm at the 2008 Olympics.

The two men who beat him in the 100 — Americans Justin Gatlin and Christian Coleman — are favoured to top the podium again, except in reverse order. Coleman has posted the world's fastest 100-m time three years in a row (including a 9.81 in March), and he's the clear favourite to win his first world title. But he's also surrounded by controversy after missing three doping tests. The rules say that counts as a positive test, but the U.S. Anti-Doping Agency dropped his case on a technicality.

Canada has two medal contenders in the 100, which remains the marquee event even without Bolt. 2016 Olympic bronze medallist Andre De Grasse is more famous but Aaron Brown beat him at the national championships for the second year in a row and has the slightly faster top time this year (9.96 to 9.97).

The Story of De Grasse and Coleman

4 years ago
Duration 1:38
Despite following similar paths in their careers, Canada's Andre De Grasse and American Christian Coleman have yet to race each other professionally in the 100 metres.. CBC Sports' Anson Henry sets up the much-anticipated 100-metre showdown at the upcoming track and field worlds.

Canada hopes to bounce back from a shutout

The Canadian team left the 2017 world championships with zero medals. And it didn't come particularly close to winning one: no Canadians finished fourth, and there were only two fifth-place showings. That was a big disappointment after the 2015 squad captured eight medals — including two gold — and then hit the podium six times at the 2016 Olympics.

No Canadian is a lock for a medal this time around, but there are a bunch with legitimate hopes. De Grasse and Brown both have a shot as opponents in the 100-m and 200-m, and as teammates in the 4x100 (they helped the Canadian relay squad win bronze at the last Olympics). Decathlete Damian Warner is looking to get back on the podium after taking bronze at the 2013 worlds, silver in 2015 and bronze at the 2016 Olympics.

Some lesser-known men are in the mix too. Brandon McBride's season-best time in the 800 is faster than all but five other guys'. Mo Ahmed has proved he can compete in big races: he finished fourth in the 5,000 at the 2016 Olympics and eighth in the 10,000 at the 2017 worlds. He's doing both races in Doha and will be joined in the 5,000 by Justyn Knight, who was ninth at the last worlds. Only five men have cleared a bigger height than high jumper Mike Mason this year, and he won a Diamond League event a month ago.

On the women's side, middle-distance runner Gabriela DeBues-Stafford has been breaking national records all season, and she just became the first Canadian woman to run the 1,500 in under four minutes. Only nine women have run that distance faster than her this year.

Pole vaulter Alysha Newman's top height this year is better than all but five other women's. Same for shot putter Brittany Crew's best throw.

The most notable absences on the Canadian team are high jumper Derek Drouin and 800-m runner Melissa Bishop-Nriagu. Drouin won the world title in 2015 and Olympic gold in '16 but has been plagued by injuries since then. Bishop-Nriagu, who won silver at the '15 worlds, shut down her season about a month ago. She's still adjusting to changes in her body after giving birth to her first child.

Events are on during daytime hours in most of Canada

Doha is seven hours ahead of Eastern Time. The competition window varies slightly from day to day, but typically events start around 9:30 a.m. ET and end around 5 p.m. ET.'s live streaming coverage starts Friday at 8:35 a.m. ET. See the official schedule with start times for every day's events here.

The heat is on

Literally. The forecast for opening day calls for a daytime high of 38 C — 53 (!) with the humidity. That's way too hot for anyone to be running and jumping around. And Doha's Khalifa International Stadium is open-air. But it's equipped with a heavy-duty air-conditioning system: a bunch of big nozzles positioned all over the stadium blow in cool air. It seems kind of like riding around in your car with the windows down and the A/C cranked up. Obviously no one's dad was consulted about this.

So what about road races (like the marathon and race walks) that take place mostly outside the stadium? They're traditionally held early in the morning, but it's already too hot in Doha at that time. So they'll start close to midnight instead. Read about how Canadian race walker Evan Dunfee is coping with this "insane" challenge here.

Do you have any idea what this is doing to the hydro bill? (Karim Jaafar/AFP/Getty Images)

Caster Semenya is not there

The reigning Olympic and world champion in the women's 800 metres was denied the chance to run for her fourth world title when a court upheld a controversial new rule governing testosterone levels. Track and field's international governing body now requires athletes with naturally elevated testosterone (like Semenya) to take drugs to suppress them before competing in women's races ranging from 400-m to the mile.

Semenya refused and challenged the rule in court. The case is now with the Swiss Supreme Court — the final stop in the appeals process. After first saying that Semenya could compete while it decides the case, the court reversed its position and said the rule would stand until a decision is made. Though her 2019 season was cut short very early, Semenya hopes the rule will be struck down and she'll be allowed to compete in her natural state at the 2020 Olympics. 

A potentially awkward moment will happen in Doha when a medal ceremony is held to award Semenya her gold medal from the 2011 worlds. Semenya finished second, but Russia's Maria Savinova was later stripped of the title for doping. Semenya declined the invitation for the ceremony, so a South African official will receive the gold on her behalf.

Russia is banned… sort of

The Russian track and field team has been banned from international events since 2015, when the country's massive state-run doping program came to light. But track's world governing body allows some Russians to compete as neutral athletes if they're considered clean. There will be 30 of them in Doha.

Olympic gold medallists Anna Chicherova (high jump) and Elena Lashmanova (race walk) are among the Russians who are not allowed to compete because they've served doping bans.

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