This means that the battery is discharged down to 10.5 volts over a 20 hour period while the total actual amp-hours that it supplies are measured. Sometimes ratings at the 6 hour rate and 100 hour rate are also given for comparison and for different applications.
Pool meets are usually no more than 4 hours, but beach meets last about 7 hours. It depends how many events are in the meet. And then if it is a really big meet (like a tournament kind of) it can last days. Hope that helps.
How many lengths must you swim in an Olympic pool to swim 1 mile? An Olympic-sized pool is 50 meters long by 25 meters wide and runs to a depth of 2.0 meters. A mile is 5,280 feet, or 1,760 yards, which is the same as 1,609.344 meters.