The men's 400 metre individual medley event at the 2009 World Aquatics Championships took place on August 2 at the Foro Italico. The heats were held during the morning session and the final were held during the evening session. This swimming event used medley swimming. Because the swimming pool is 50 metres long, this race consisted of eight lengths of the pool. The first two lengths were swum using the butterfly stroke, the second pair with the backstroke, the third pair of lengths in breaststroke, and the final two were freestyle. Unlike other events using freestyle, swimmers could not use butterfly, backstroke, or breaststroke for the freestyle leg; most swimmers use the front crawl in freestyle events.
The swimming portion of the 2011 FINA World Championships was held July 24–31 at the Shanghai Oriental Sports Center in Shanghai, China. Swimming is one of five aquatic disciplines at the championships.
The men's 400 metre freestyle competition of the swimming events at the 2011 World Aquatics Championships took place July 24. The heats and final took place on July 24.
The women's 200 metre individual medley competition of the swimming events at the 2011 World Aquatics Championships took place July 24 and 25. The heats and semifinals took place July 24 and the final was held July 25.
The men's 50 metre butterfly competition of the swimming events at the 2011 World Aquatics Championships took place July 24 and 25. The heats and semifinals took place July 24 and the final was held July 25.
The women's 400 metre freestyle competition of the swimming events at the 2011 World Aquatics Championships took place July 24. The heats and the final took place on July 24.
The men's 50 metre freestyle competition of the swimming events at the 2011 World Aquatics Championships was held on July 29 with the heats and the semifinals and July 30 with the final.
The men's 100 metre backstroke competition of the swimming events at the 2011 World Aquatics Championships was held on July 25 with the preliminary round and the semifinals and July 26 with the final.
The men's 200 metre butterfly competition of the swimming events at the 2011 World Aquatics Championships was held on July 26 with the heats and the semifinals and July 27 with the final.
The men's 200 metre individual medley competition of the swimming events at the 2011 World Aquatics Championships took place July 27 and 28. The heats and semifinals took place July 27 and the final was held July 28.
The men's 100 metre freestyle competition of the swimming events at the 2011 World Aquatics Championships was held on July 27 with the heats and the semifinals and July 28 with the final.
The men's 200 metre backstroke competition of the swimming events at the 2011 World Aquatics Championships was held on July 28 with the heats and the semifinals and July 29 with the final.
The men's 200 metre breaststroke competition of the swimming events at the 2011 World Aquatics Championships was held on July 28 with the heats and the semifinals and July 29 with the final.
The men's 1500 metre freestyle competition of the swimming events at the 2011 World Aquatics Championships was held on July 30 with the heats and the semifinals and July 31 with the final.
The men's 100 metre butterfly competition of the swimming events at the 2011 World Aquatics Championships was held on July 29 with the heats and the semifinals and July 30 with the final.
The men's 4 × 100 metre medley relay competition of the swimming events at the 2011 World Aquatics Championships took place July 31. The heats and final took place July 31.
The women's 50 metre breaststroke competition of the swimming events at the 2011 World Aquatics Championships was held on July 30 with the heats and the semifinals and July 31 with the final.
The men's 50 metre backstroke competition of the swimming events at the 2011 World Aquatics Championships was held on July 30 with the heats and the semifinals and July 31 with the final.
The women's 4 x 100 metre medley competition of the swimming events at the 2011 World Aquatics Championships was held on July 30 with the heats and the final.
The women's 400 metre individual medley competition of the swimming events at the 2011 World Aquatics Championships was held on July 31 with the heats the final.
